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19-0275; Rev 0; 12/94
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators
_______________General Description
The MAX882/MAX883/MAX884 linear regulators maximize battery life by combining ultra-low supply currents and low dropout voltages. They feature 200mA output current capability at up to +125C junction temperature and come in a 1.5W SOIC package. The 1.5W package (compared to 0.47W for standard SOIC packages) allows a wider operating range for the input voltage and output current. The MAX882/MAX883/MAX884 use a Pchannel MOSFET pass transistor to maintain a low 11A (15A max) supply current from no-load to the full 200mA output. Unlike earlier bipolar regulators, there are no PNP base current losses that increase with output current. And, in dropout, the MOSFET does not suffer from excessive base currents that occur when PNP transistors go into saturation. Typical dropout voltages are 220mV at 5V and 200mA, or 320mV at 3.3V and 200mA. The MAX882 features a 7A standby mode that disables the output but keeps the reference, low-battery comparator, and biasing circuitry alive. The MAX883/MAX884 feature a shutdown (OFF) mode that turns off all circuitry, reducing supply current to less than 1A. All three devices include a low-battery-detection comparator, foldback current limiting, reverse-current protection, and thermal overload protection. The output is preset at 3.3V for the MAX882/MAX884 and 5V for the MAX883. In addition, all devices employ Dual ModeTM operation, allowing user-adjustable outputs from 1.25V to 11V using external resistors. The input voltage supply range is 2.7V to 11.5V. For low-dropout linear regulators with output currents up to 500mA, refer to the MAX603/MAX604 data sheet.
____________________________Features
o Guaranteed 200mA Output Current at TJ = +125C, with Foldback Current Limiting o High-Power (1.5W) 8-Pin SO Package o Dual ModeTM Operation: Fixed or Adjustable Output from 1.25V to 11V o Large Input Range (2.7V to 11.5V) o Internal 1.1 P-Channel Pass Transistor Draws No Base Current o Low 220mV Dropout Voltage at 200mA Output Current o 11A Typical Quiescent Current o 1A (max) Shutdown Mode or 7A (typ) Standby Mode o Low-Battery Detection Comparator o Reverse-Current Protection o Thermal Overload Protection
MAX882/MAX883/MAX884
______________Ordering Information
PART MAX882CPA MAX882CSA MAX882C/D MAX882EPA MAX882ESA MAX882MJA TEMP. RANGE 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -55C to +125C PIN-PACKAGE 8 Plastic DIP 8 SO Dice* 8 Plastic DIP 8 SO 8 CERDIP**
________________________Applications
Pagers and Cellular Phones 3.3V and 5V Regulators 1.25V to 11V Adjustable Regulators High-Efficiency Linear Regulators Battery-Powered Devices Portable Instruments Solar-Powered Instruments
Ordering Information continued at end of data sheet. * Dice are tested at TJ = +25C, DC parameters only. ** Contact factory for availability.
__________Typical Operating Circuit
ON/OFF OFF (STBY) OUTPUT VOLTAGE
__________________Pin Configuration
TOP VIEW
LBO SET GND OUT ( ) ARE FOR MAX882 1 2 3 4 8 LBI INPUT VOLTAGE CIN O.1F BATTERY IN LBI
MAX882 MAX883 MAX884
GND
OUT
MAX882 MAX883 MAX884
DIP/SO
7 OFF (STBY) 6 GND 5 IN
SET
COUT 2.2F
( ) ARE FOR MAX882
TMDual-Mode is a trademark of Maxim Integrated Products. ________________________________________________________________ Maxim Integrated Products 1
Call toll free 1-800-998-8800 for free samples or literature.
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (IN or OUT to GND).......................-0.3V to +12V Output Short-Circuit Duration .........................................1 minute Continuous Output Current ...............................................300mA LBO Output Current ............................................................50mA LBO Output Voltage and LBI, SET, STBY, OFF Input Voltages ................-0.3V to the greater of (IN + 0.3V) or (OUT + 0.3V) Continuous Power Dissipation (TJ = +70C) Plastic DIP (derate 9.09mW/C above +70C) ............727mW High-Power SO (derate 18.75mW/C above +70C) .......1.5W CERDIP (derate 8.00mW/C above +70C) .................640mW Operating Temperature Ranges MAX88_C_A ........................................................0C to +70C MAX88_E_A .....................................................-40C to +85C MAX88_MJA ..................................................-55C to +125C Junction Temperature .....................................................+150C Storage Temperature Range .............................-65C to +160C Lead Temperature (soldering, 10sec) .............................+300C
Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VIN = 6V (MAX883) or VIN = 4.3V (MAX882/MAX884), COUT = 2.2F, STBY or OFF = VIN, SET = GND, LBI = VIN, TJ = TMIN to TMAX, unless otherwise noted. Typical values are at TJ = +25C.) (Note 1) PARAMETER Input Voltage Range SYMBOL VIN CONDITIONS MAX88_C_A SET = OUT, RL = 1k MAX88_E_A MAX88_MJA IOUT = 10A-200mA, TJ +125C MAX883, 6.0V VIN 11.5V IOUT = 10A-250mA, TJ +85C IOUT = 10A-250mA, TJ +70C IOUT = 10A-150mA, TJ +125C MAX882/MAX884, 4.3V VIN 11.5V IOUT = 10A-200mA, TJ +85C IOUT = 10A-200mA, TJ +70C IOUT = 1mA to 200mA Load Regulation VLDR IOUT = 1mA to 150mA Line Regulation VLNR MAX883C_A/E_A MAX883MJA MAX882, MAX884 30 10 110 220 160 320 11 15 60 100 150 100 40 220 440 320 640 15 30 25 40 A mV mV mV 3.15 3.30 3.45 4.75 5.00 5.25 mV mV MIN 2.7 2.9 3.0 TYP MAX 11.5 11.5 11.5 V UNITS
Output Voltage (Note 2)
VOUT
(VOUT + 0.5V) < VIN < 11.5V, IOUT = 10mA MAX883 IOUT = 100mA IOUT = 200mA IOUT = 100mA IOUT = 200mA MAX88_C_A/E_A MAX88_MJA MAX88_C_A/E_A MAX88_MJA
Dropout Voltage (Note 3)
VDO MAX882/MAX884 SET = OUT, VIN = 6V VIN = 11.5V
Quiescent Current
IQ
2
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5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators
ELECTRICAL CHARACTERISTICS (continued)
(VIN = 6V (MAX883) or VIN = 4.3V (MAX882/MAX884), COUT = 2.2F, STBY or OFF = VIN, SET = GND, LBI = VIN, TJ = TMIN to TMAX, unless otherwise noted. Typical values are at TJ = +25C.) (Note 1) PARAMETER STBY Quiescent Current (Note 4) SYMBOL CONDITIONS STBY = 0V, VIN = 6V, SET = OUT MAX882C_A/E_A MAX882MJA 10 0.01 MIN TYP 7 MAX 15 30 25 40 1 5 10 1 3 10 170 430 160 10 VOUT = 4.5V VRTH VOUT = 3.0V MAX883_A MAX882_A, MAX884_A 6 6 7 A 0.01 1 200 65 150 1.16 1.15 65 1.20 0.01 1.20 7 VLBI = 1.5V ILBO SINK = 1.2mA, VLBI =1V, 3V < VIN < 11.5V, SET = OUT VLBI = VIN, VLBO = VIN VIN = 11.5V, VOUT = 2V, SET = OUT MAX88_C_A MAX88_E_A MAX88_MJA 0.01 90 0.01 0.01 50 250 0.1 1 3 10 A 1.24 50 1.25 30 % of VOUT s mV V nA V mV nA mV A 20 20 mV mA C C A A A UNITS
MAX882/MAX883/MAX884
IQ STBY
MAX882C_A/E_A STBY = 0V, VIN =11.5V, SET = OUT MAX882MJA OFF = 0V, RL = 1k, VIN = 11.5V (MAX883/MAX884) VIN = 11.5V, SET = OUT VOUT < 0.8V VOUT > 0.8V and VIN - VOUT > 0.7V MAX88_C_A MAX88_E_A MAX88_MJA MAX88_C_A MAX88_E_A MAX88_MJA
OFF Quiescent Current
IQ OFF
Minimum Load Current
IOUT(MIN)
Foldback Current Limit (Note 5) Thermal Shutdown Temperature Thermal Shutdown Hysteresis Reverse-Current-Protection Threshold (Note 6)
ILIM TSD TSD
Reverse Leakage Current
IRVL
MAX882: VIN = 0V, STBY = 0V, VOUT = 3.0V MAX883/MAX884: VIN = 0V, OFF = 0V, VOUT = 3.0V RL = 1k, COUT = 2.2F VIN = 9V, RL = 33, OFF from 0V to VIN, 0% to 95% of VOUT For internal feedback For external feedback SET = OUT, RL = 1k VSET = 1.5V or 0V LBI signal falling
Startup Overshoot Time Required to Exit OFF or STBY Modes Dual ModeTM SET Threshold SET Reference Voltage SET Input Leakage Current LBI Threshold Voltage LBI Hysteresis LBI Input Leakage Current LBO Output Low Voltage LBO Output Leakage Current
VOSH TSTART VSET TH VSET ISET VLBI VLBI ILBI VLBOL ILBO LKG
OUT Leakage Current
IOUT LKG
_______________________________________________________________________________________
3
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
ELECTRICAL CHARACTERISTICS (continued)
(VIN = 6V (MAX883) or VIN = 4.3V (MAX882/MAX884), COUT = 2.2F, STBY or OFF = VIN, SET = GND, LBI = VIN, TJ = TMIN to TMAX, unless otherwise noted. Typical values are at TJ = +25C.) (Note 1) PARAMETER STBY Threshold Voltage STBY Hysteresis STBY Input Leakage Current SYMBOL V STBY V STBY ISTBY VIL OFF OFF Threshold Voltage VIH OFF V STBY = VIN or 0V In off mode In on mode, SET = OUT, VIN < 6V CONDITIONS STBY signal falling MAX882_A MAX882_A MAX882_A MAX883_A, MAX884_A MAX883_A, MAX884_A 2.0 3.0 0.01 250 50 nA VRMS MIN 1.15 TYP 1.20 7 0.01 50 0.4 V MAX 1.25 UNITS V mV nA
In on mode, SET = OUT, MAX883_A, 6V < VIN < 11.5V MAX884_A V OFF = VIN or 0V 10Hz to 10kHz, SET = OUT, RL = 1k, COUT = 2.2F
OFF Input Leakage Current Output Noise (Note 7) Note 1:
IOFF en
Note 2:
Note 3:
Note 4: Note 5: Note 6:
Note 7:
Electrical specifications are measured by pulse testing and are guaranteed for a junction temperature (TJ) within the operating temperature range, unless otherwise noted. When operating C and E grade parts up to a TJ of +125C, expect performance similar to M grade specifications. For TJ between +125C and +150C, the output voltage may drift more. (VIN - VOUT) is limited to keep the product (IOUT x (VIN - VOUT)) from exceeding the package power dissipation limits. See Figure 5. Therefore, the combination of high output current and high supply voltage is not tested. Output current at TJ = +125C is guaranteed by guard banding tests at TJ = +85C and +70C. Dropout Voltage is (VIN - VOUT) when VOUT falls to 100mV below its nominal value at VIN = (VOUT + 2V). For example, the MAX883 is tested by measuring the VOUT at VIN = 7V, then VIN is lowered until VOUT falls 100mV below the measured value. The difference (VIN - VOUT) is then measured and defined as VDO. Since standby mode inhibits the output but keeps all biasing circuitry alive, the Standby Quiescent Current is similar to the normal operating quiescent current. Foldback Current Limit was characterized by pulse testing to remain below the maximum junction temperature (not production tested). The Reverse-Current Protection Threshold is the output/input differential voltage (VOUT - VIN) at which reverse-current protection switchover occurs and the pass transistor is turned off. See the section Reverse Current Protection in the Detailed Description. Noise is tested using a bandpass amplifier with two poles at 10Hz and two poles at 10kHz.
4
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5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators
__________________________________________Typical Operating Characteristics
(VIN = 7V for MAX883, VIN = 5.3V for MAX882/MAX884, OFF or STBY = VIN, SET = GND, LBI = VIN, LBO = OPEN, CIN = COUT = 2.2F, RL = 1k, TA = +25C, unless otherwise noted.)
OUTPUT VOLTAGE AND QUIESCENT CURRENT vs. LOAD CURRENT
QUIESCENT CURRENT (A) MAX882/4-01 101 NORMALIZE OUTPUT VOLTAGE (%) 100 99 98 97 96 OUTPUT VOLTAGE NORMALIZED TO OUTPUT VOLTAGE AT 1mA 0.1 1 10 IQ 5 0 100 250 VOUT = 5V (MAX883) VOUT = 3.3V (MAX882/MAX884) 30 25 20 15 10 104 NORMALIZED OUTPUT VOLTAGE (%) 103 102 101 100 99 98 97 96 -55 -35 -15 5 25 45 65 85 105 125 TEMPERATURE (C)
MAX882/MAX883/MAX884
OUTPUT VOLTAGE vs. TEMPERATURE
MAX882/4-04a
95 0.01
LOAD CURRENT (mA)
OUTPUT VOLTAGE AND QUIESCENT CURRENT vs. SUPPLY VOLTAGE
MAX882/4-03
QUIESCENT CURRENT vs. TEMPERATURE
MAX882/4-04
6 5 OUTPUT VOLTAGE (V) 4 VOUT = 3.3V (MAX882/MAX884) 3 2 IQ (MAX882/MAX884)
16 14 12 10 8 6 IQ (MAX883)
15 QUIESCENT CURRENT (A)
VOUT = 5V (MAX883)
QUIESCENT CURRENT (A)
12
9
6
3
0 2 3 4 5 6 7 8 9 10 11 12 SUPPLY VOLTAGE (V)
4
0 -55 -35 -15 5 25 45 65 85 105 125 TEMPERATURE (C)
DROPOUT VOLTAGE vs. LOAD CURRENT
MAX882/4-05
10Hz to 10kHz OUTPUT NOISE
MAX882/4-06
0.6 0.5 DROPPUT VOLTAGE (V) 0.4 0.3 0.2 VOUT = 5V (MAX883) 0.1 0 0 50 100 150 200 250 VOUT = 3.3V (MAX882/MAX884)
OUTPUT NOISE (1mV/div)
MAX883 VOUT = 5V 10ms/div
300
LOAD CURRENT (mA)
_______________________________________________________________________________________
5
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
____________________________Typical Operating Characteristics (continued)
(VIN = 7V for MAX883, VIN = 5.3V for MAX882/MAX884, OFF or STBY = VIN, SET = GND, LBI = VIN, LBO = OPEN, CIN = COUT = 2.2F, RL = 1k, TA = +25C, unless otherwise noted.)
LINE-TRANSIENT RESPONSE LOAD-TRANSIENT RESPONSE
A
A
B
B
500s/div MAX883: VOUT = 5V, CIN = 0F, tR = 15s, tF = 13s A: VIN = 8V (HIGH) / VIN = 7V (LOW) B: OUTPUT VOLTAGE (100mV/div)
1ms/div MAX883: VOUT = 5V, tR = 24s, tF = 44s A: OUTPUT VOLTAGE (100mV/div) B: IOUT = 250mA (HIGH) / IOUT = 50mA (LOW)
OVERSHOOT AND TIME EXITING SHUTDOWN MODE
5 RL = 100 B A 5V LBO LOW VOLTAGE (V) 4
LBO LOW VOLTAGE vs. SINK CURRENT
MAX882/4-10
3
MAX882/MAX884
2
MAX883
0V
1
0 500s/div A: OFF PIN VOLTAGE (1V/div): RISE TIME = 9s B: MAX883 OUTPUT VOLTAGE (1V/div): DELAY = 135s, RISE TIME = 67s, OVERSHOOT = 0% 0.1 1 10 50 SINK CURRENT (mA)
6
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5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators
______________________________________________________________Pin Description
PIN MAX882 MAX883/ MAX884 1 2 3, 6 4 5 -- 7 8 NAME FUNCTION Low-Battery Output is an open-drain output that goes low when LBI is less than 1.2V. Connect to IN or OUT through a pull-up resistor. LBO is undefined during shutdown mode (MAX883/MAX884). Feedback for setting the output voltage. Connect to GND to set the output voltage to the preselected 3.3V or 5V. Connect to an external resistor network for adjustable-output operation. Ground pins--also function as heatsinks in the SO package. All GND pins must be soldered to the circuit board for proper power dissipation. Connect to large copper pads or planes to channel heat from the IC. Regulator Output. Fixed or adjustable from 1.25V to 11.0V. Sources up to 200mA. Bypass with a 2.2F capacitor. Regulator Input. Supply voltage can range from 2.7V to 11.5V. Standby. Active-low comparator input. Connect to GND to disable the output or to IN for normal operation. A resistor network (from IN) can be used to set a standby mode threshold. Shutdown. Active-low logic input. In OFF mode, supply current is reduced below 1A and VOUT = 0V Low-Battery comparator Input. Tie to IN when not used.
MAX882/MAX883/MAX884
1 2 3, 6 4 5 7 -- 8
LBO SET GND OUT IN STBY OFF LBI
_______________Detailed Description
The MAX882/MAX883/MAX884 are micropower, lowdropout linear regulators designed primarily for batterypowered applications. They feature Dual-ModeTM operation, allowing a fixed output of 5V for the MAX883 and 3.3V for the MAX882/MAX884, or an adjustable output from 1.25V to 11V. These devices supply up to 200mA while requiring less than 15A quiescent current. As illustrated in Figure 1, they consist of a 1.20V reference, error amplifier, MOSFET driver, P-channel pass transistor, dualmode comparator and feedback voltage divider. The 1.20V reference is connected to the error amplifier's inverting input. The error amplifier compares this reference with the selected feedback voltage and amplifies the difference. The MOSFET driver reads the error signal and applies the appropriate drive to the P-channel pass transistor. If the feedback voltage is lower than the reference, the pass transistor's gate is pulled lower, allowing more current to pass and increasing the output voltage. If the feedback voltage is too high, the pass transistor gate is pulled up, allowing less current to pass to the output. The output voltage is fed back through either an internal resistor voltage divider connected to the OUT pin, or an external resistor network connected to the SET pin. The dual-mode comparator examines the SET pin voltage and selects the feedback path used. If the SET pin is below 65mV, internal feedback is used and the output voltage is regulated to 5V for the MAX883 or
3.3V for the MAX882/MAX884. Additional blocks include a foldback current limiter, reverse-current protection, a thermal sensor, shutdown or standby logic, and a low-battery-detection comparator.
Internal P-Channel Pass Transistor
The MAX882/MAX883/MAX884 feature a 200mA Pchannel MOSFET pass transistor. This provides several advantages over similar designs using PNP pass transistors, including longer battery life. The P-channel MOSFET requires no base drive, which reduces quiescent current considerably. PNP based regulators waste large amounts of current in dropout when the pass transistor saturates. They also use high basedrive currents under large loads. The MAX882/MAX883/ MAX884 do not suffer from these problems and consume only 11A of quiescent current during light loads, heavy loads, and dropout.
Output Voltage Selection
The MAX882/MAX883/MAX884 feature Dual ModeTM operation. In preset voltage mode, the MAX883's output is set to 5V and the MAX882/MAX884's output is set to 3.3V, using internal trimmed feedback resistors. Select this mode by connecting SET to ground. In preset voltage mode, impedances between SET and ground should be less than 100k. Otherwise, spurious conditions could cause the voltage at SET to exceed the 65mV dual-mode threshold.
7
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5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
IN LBI LBO N ERROR AMP LOW-BATTERY COMPARATOR MOSFET DRIVER WITH FOLDBACK CURRENT LIMIT P REVERSECURRENT PROTECTION
OFF (STBY)
SHUTDOWN LOGIC 1.20V REFERENCE DUAL-MODE COMPARATOR R1
OUT
SET
THERMAL SENSOR GND
R2 65mV
( ) ARE FOR MAX882
Figure 1. MAX882/MAX883/MAX884 Functional Diagram
In adjustable mode, the user selects an output voltage in the 1.25V to 11V range by connecting two external resistors, used as a voltage divider, to the SET pin (Figure 2). The output voltage is set by the following equation: R1 VOUT = VSET 1 + R2 where VSET = 1.20V. To simplify resistor selection: V R1 = R2 OUT - 1 VSET Since the input bias current at SET is nominally zero, large resistance values can be used for R1 and R2 to minimize power consumption without losing accuracy. Up to 1.5M is acceptable for R2. Since the VSET tolerance is less than 40mV, the output can be set using fixed resistors instead of trim pots.
Standby Mode (MAX882)
The MAX882 has a standby feature that disconnects the input from the output when STBY is brought low, but keeps all other circuitry awake. In this mode, VOUT drops to 0V, and the internal biasing circuitry (including the low-battery comparator) remains on. The maximum quiescent current during standby is 15A. STBY is a comparator input with the other input internally tied to the reference voltage. Use a resistor network as shown in Figure 3 to set a standby-mode threshold voltage for undervoltage lockout. Connect STBY to IN for normal operation.
OFF Mode (MAX883/MAX884)
A low-logic input on the OFF pin shuts down the MAX883/MAX884. In this mode, the pass transistor, control circuit, reference, and all biases are turned off, and the supply current is reduced to less than 1A. LBO is undefined in OFF mode. Connect OFF to IN for normal operation.
8
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5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
INPUT VOLTAGE IN LBI R1 OUT OUTPUT VOLTAGE INPUT VOLTAGE R1 LOAD R2 COUT 2.2F CIN O.1F STBY COUT 2.2F
IN LBI
OUT
OUTPUT VOLTAGE
MAX882 OFF (STBY) MAX883 MAX884
CIN O.1F GND
MAX882
SET
R2
GND
SET
( ) ARE FOR MAX882 VSTBY TRIP = VSTBY R1 + R2 VOUT = VSET , VSET = 1.20V R2
R1+ R2 , VSTBY = 1.20V R2
Figure 2. Adjustable Output Using External Feedback Resistors
Figure 3. Setting an Undervoltage Lockout Threshold Using STBY
Foldback Current Limiting
The MAX882/MAX883/MAX884 also include a foldback current limiter. It monitors and controls the pass transistor's gate voltage, estimating the output current and limiting it to 430mA for output voltages above 0.8V and (VIN - VOUT) > 0.7V. If the output voltage drops below 0.8V, implying a short-circuit condition, the output current is limited to 170mA. The output can be shorted to ground for 1 minute without damaging the device if the package can dissipate (VIN x 170mA) without exceeding TJ = +150C. When the output is greater than 0.8V and (VIN - VOUT) < 0.7V (dropout operation), no current limiting is allowed, to provide maximum load drive.
Power Dissipation and Operating Region
Maximum power dissipation of the MAX882/MAX883/ MAX884 depends on the thermal resistance of the case and circuit board, the temperature difference between the die junction and ambient air, and the rate of air flow. The power dissipation across the device is P = IOUT (VIN - VOUT). The resulting power dissipation is as follows: (TJ - TA ) P= ( JB + BA ) where (TJ - TA) is the temperature difference between the MAX882/MAX883/MAX884 die junction and the surrounding air, JB (or JC) is the thermal resistance of the package chosen, and BA is the thermal resistance through the printed circuit board, copper traces, and other materials to the surrounding air. The 8-pin small-outline package for the MAX882/ MAX883/MAX884 features a special lead frame with a lower thermal resistance and higher allowable power dissipation. This package's thermal resistance package is JB = 53C/W, compared with JB = 110C/W for an 8-pin plastic DIP package and JB = 125C/W for an 8pin ceramic DIP package.
Thermal Overload Protection
Thermal overload protection limits total power dissipation in the MAX882/MAX883/MAX884. When the junction temperature exceeds T J =+160C, the thermal sensor sends a signal to the shutdown logic, turning off the pass transistor and allowing the IC to cool. The thermal sensor turns the pass transistor on again after the IC's junction temperature cools by 10C, resulting in a pulsed output during thermal overload conditions. Thermal overload protection is designed to protect the MAX882/MAX883/MAX884 if fault conditions occur. It is not intended to be used as an operating mode. Prolonged operation in thermal shutdown mode may reduce the IC's reliability. For continual operation, do not exceed the absolute maximum junction temperature rating of TJ = +150C.
_______________________________________________________________________________________
9
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
1.6 1.5 POWER DISSIPATION (W) 1.4 1.3 1.2 1.1 1.0 0.9 0.1cm2 0.0155in2
MAX882/4-fig04
MAXIMUM OUTPUT CURRENT (mA)
150
HIGHPOWER SOIC PLASTIC DIP CERAMIC DIP
100
50
1cm2 0.155in2
10cm2 1.55in2
100cm2 15.5in2
0 2 3 4
OPERATING REGION AT TA = +25C TJ = +125C 56 7 8
9 10 11 12 13
SUPPLY VOLTAGE (V)
COPPER GROUND PAD AREA
Figure 4. Typical Maximum Power Dissipation vs. Ground Pad Area
Figure 5a. Safe Operating Regions: MAX882/MAX884 Maximum Output Current vs. Supply Voltage
The GND pins of the MAX882/MAX883/MAX884 SOIC package perform the dual function of providing an electrical connection to ground and channeling heat away. Connect all GND pins to ground using a large pad or ground plane. Where this is impossible, place a copper plane on an adjacent layer. For a given power dissipation, the pad should exceed the associated dimensions in Figure 4. Figure 4 assumes the IC is in an 8-pin small-outline package that has a maximum junction temperature of +125C and is soldered directly to the pad; it also has a +25C ambient air temperature and no other heat sources. Use larger pad sizes for other packages, lower junction temperatures, higher ambient temperatures, or conditions where the IC is not soldered directly to the heat-sinking ground pad. When operating C and E grade parts up to a TJ of +125C, expect performance similar to M grade specifications. For TJ between +125C and +150C, the output voltage may drift more. The MAX882/MAX883/MAX884 can regulate currents up to 250mA and operate with input voltages up to 11.5V, but not simultaneously. High output currents can only be sustained when input-output differential voltages are small, as shown in Figure 5. Maximum power dissipation depends on packaging, temperature, and air flow. The maximum output current is as follows: IOUT(MAX) = P(TJ - TA ) (VIN - VOUT )100C
MAXIMUM OUTPUT CURRENT (mA)
MAXIMUM CURRENT 200
TYPICAL DROPOUT VOLTAGE LIMIT
MAXIMUM POWER DISSIPATION LIMIT
HIGHPOWER SOIC
MAXIMUM SUPPLY VOLTAGE LIMIT
150
PLASTIC DIP
100
CERAMIC DIP
50
OPERATING REGION AT TA = +25C TJ = +125C 5 6 7 8 9 10 11 12
0 4 13 SUPPLY VOLTAGE (V)
Figure 5b. Safe Operating Regions: MAX883 Maximum Output Current vs. Supply Voltage
where P is derived from Figure 4.
10 ______________________________________________________________________________________
MAX882/4-05b
250
MAXIMUM SUPPLY VOLTAGE LIMIT
TYPICAL DROPOUT VOLTAGE LIMIT
MAX883, VOUT = 5V 8-PIN SO PACKAGE 77.4cm2, SINGLE-SIDED BOARD 1oz. COPPER GLASS EPOXY, TJ = +125C, TA = +25C, STILL AIR
MAXIMUM CURRENT 200
MAXIMUM POWER DISSIPATION LIMIT
MAX882/4-05a
250
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
OUTPUT VOLTAGE ON/OFF BATTERY R1 OFF (STBY) R3 LBO POWERCOUT FAIL INDICATION 2.2F INPUT VOLTAGE BATTERY CIN O.1F SET * OFF (STBY) IN LBI OUT OUTPUT VOLTAGE
IN
OUT
LBI CIN O.1F R2
MAX882 MAX883 MAX884
SET
GND
MAX882 MAX883 MAX884
GND
COUT 2.2F
( ) ARE FOR MAX882 ( ) ARE FOR MAX882 VLBI TRIP = VLBI R1 + R2 , VLBI = 1.20V R2 * OPTIONAL REVERSE BATTERY PROTECTION
Figure 6. Using the Low-Battery Comparator to Monitor Battery Voltage
Figure 7. Typical 3.3V or 5V Linear Regulator Circuit
Reverse-Current Protection
The MAX882/MAX883/MAX884 have a unique protection scheme that limits reverse currents when the input voltage falls below the output. It monitors the voltages on IN and OUT and switches the IC's substrate and power bus to the more positive of the two. The control circuitry is then able to remain functioning and turn the pass transistor off, limiting reverse currents back through to the input of the device. In this mode, typical current into OUT to GND is 15A at VOUT = 3.3V and 50A at VOUT = 5V. Reverse-current protection activates when the voltage on IN falls 6mV (or 20mV maximum) below the voltage on OUT. Before this happens, currents as high as several milliamperes can flow back through the device.
__________Applications Information
The MAX882/MAX883/MAX884 are series linear regulators designed primarily for battery-powered systems. Figure 7 shows a typical application.
Standby Mode vs. OFF Mode
STBY is a comparator input that allows the user to set the standby-mode threshold voltage, while OFF is a logic-level input. When in standby mode, the output is disconnected from the input, but the biasing circuitry (including the low-battery comparator) is kept alive, causing the device to draw around 7A. Standby mode is useful in applications where a low-battery comparator function is still needed in shutdown. A logic low at the OFF pin turns off all biasing circuitry, including the LBI/LBO comparator, and reduces supply current to less than 1A. OFF mode is useful for maximizing battery life. There is little difference in the time it takes to exit standby mode or OFF mode.
Low-Battery-Detection Comparator
The MAX882/MAX883/MAX884 provide a low-battery comparator that compares the voltage on the LBI pin to the 1.20V internal reference. LBO, an open-drain output, goes low when LBI is below 1.20V. Hysteresis of 7mV has been added to the low-battery comparator to provide noise immunity during switching. LBO remains functional in standby mode for the MAX882, but is undefined in OFF mode for the MAX883 and MAX884. Tie LBI to IN when not used. Use a resistor-divider network as shown in Figure 6 to set the low-battery trip voltage. Current into the LBI input is 50nA maximum, so R2 can be as large as 1M. Add extra noise immunity by connecting a small capacitor from LBI to GND. Additional hysteresis can be added by connecting a high-value resistor from LBI to LBO.
* Tie LBI to IN when not used.
Output Capacitor Selection and Regulator Stability
An output filter capacitor is required at the MAX882/ MAX883/MAX884 OUT pin. The minimum output capacitance required for stability is 2.2F.
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11
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
80 70 60 IOUT = 1mA PSRR (dB) PSRR (dB) 50 40 30 20 10 0 100 101 102 103 104 105 106 FREQUENCY (Hz) MAX884 VIN = 1VP-P CIN = 0F COUT = 2.2F 40 30 C 20 10 IOUT = 100mA 0 101 102 103 104 105 106 FREQUENCY (Hz) MAX883 VIN = 1VP-P CIN = 0F IOUT = 100mA B A 60 50 A: COUT = 1F B: COUT = 10F C: COUT = 100F
MAX882/4-8a
Figure 8a. Power-Supply Rejection Ratio vs. Ripple Frequency for Light and Heavy Loads
Figure 8b. Power-Supply Rejection Ratio vs. Ripple Frequency for Various Output Capacitances
MAX882/4-8b
The filter capacitor's size depends primarily on the desired power-up time and load-transient responses. Load-transient response is improved by using larger output capacitors. The output capacitor's equivalent series resistance (ESR) will not affect stability as long as you observe the minimum capacitance requirement. The type of capacitor selected is not critical, but it must remain above the minimum value over the full operating temperature range.
Noise
The MAX882/MAX883/MAX884 exhibit up to 4mVp-p of noise during normal operation. This is negligible in most applications. When using the MAX882/MAX883/ MAX884 for applications that include analog-to-digital converters (ADCs) with resolutions greater than 12 bits, consider the ADC's power-supply rejection specifications. Refer to the output noise plot in the Typical Operating Characteristics section.
Input Bypass Capacitor
Normally, use 0.1F to 10F capacitors on the MAX882/ MAX883/MAX884 input. The best value depends primarily on the power-up slew rate of VIN, and on load and line transients. Larger input capacitor values provide better supply-noise rejection and line-transient response, as well as improved performance, when the supply has a high AC impedance. The type of input bypass capacitor used is not critical.
PSRR and Operation from Sources Other than Batteries
The MAX882/MAX883/MAX884 are designed to achieve low dropout voltages and low quiescent currents in battery-powered systems. However, to gain these benefits, the devices must trade away powersupply noise rejection, as well as swift response to supply variations and load transients. For a 1mA load current, power-supply rejection ranges from 60dB down to 20dB at 2kHz. At higher frequencies, the circuit depends primarily on the characteristics of the output capacitor, and the PSRR increases (Figure 8).
12
______________________________________________________________________________________
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators
Input-Output (Dropout) Voltage
A regulator's minimum input-output voltage differential (or dropout voltage) determines the lowest usable supply voltage. In battery-powered systems, this determines the useful end-of-life battery voltage. Because the MAX882/MAX883/MAX884 use a P-channel MOSFET pass transistor, their dropout voltage is a function of RDS(ON) multiplied by the load current (see Electrical Characteristics). Quickly stepping up the input voltage from the dropout voltage can result in overshoot.
MAX882/MAX883/MAX884
INPUT VOLTAGE IN LBI R1 STBY CIN O.1F OUT
OUTPUT VOLTAGE
MAX882
COUT 2.2F
D2
R2
GND
SET
BACKUP BATTERY
Short-Term Battery Backup Using the MAX882
Figure 9 illustrates a scheme for implementing battery backup for 3.3V circuits using the MAX882. When the supply voltage drops below some user-specified value based on resistors R1 and R2, the standby function activates, turning off the MAX882's output. Under these conditions, the backup battery supplies power to the load. Reverse current protection prevents the battery from draining back through the regulator to the input. This application is limited to short-term battery backup for 3.3V circuits. The current drawn by the MAX882's OUT pin at 3.3V during reverse current protection is typically 8A. It should not be used with the MAX883 and MAX884, since the OFF pin is a logic input, and indeterminate inputs can cause the regulator to turn on intermittently, draining the battery.
Figure 9. Short-Term Battery Backup Using the MAX882
When operating from sources other than batteries, supply-noise rejection and transient response can be improved by increasing the values of the input and output capacitors and employing passive filtering techniques. Do not use power supplies with ripple voltage exceeding 200mV at 100kHz.
Overshoot and Transient Considerations
The Typical Operating Characteristics section shows power-up, supply, and load-transient response graphs. On the load-transient graphs, two components of the output response can be observed: a DC shift from the output impedance due to the different load currents, and the transient response. Typical transients for step changes in the load current from 50mA to 250mA are 200mV. Increasing the output capacitor's value attenuates transient spikes. During recovery from shutdown, overshoot is negligible if the output voltage has been given time to decay adequately. During power-up from VIN = 0V, overshoot is typically less than 1% of VOUT.
Reverse Battery Protection
Reverse battery protection can be added by including an inexpensive Schottky diode between the battery input and the regulator circuit, as shown in Figure 7. However, the dropout voltage of the regulator will be increased by the forward voltage drop of the diode. For example, the forward voltage of a standard 1N5817 Schottky diode is typically 0.29V at 200mA.
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13
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
_Ordering Information (continued)
PART MAX883CPA MAX883CSA MAX883C/D MAX883EPA MAX883ESA MAX883MJA MAX884CPA MAX884CSA MAX884C/D MAX884EPA MAX884ESA MAX884MJA TEMP. RANGE 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -55C to +125C 0C to +70C 0C to +70C 0C to +70C -40C to +85C -40C to +85C -55C to +125C PIN-PACKAGE 8 Plastic DIP 8 SO Dice* 8 Plastic DIP 8 SO 8 CERDIP** 8 Plastic DIP 8 SO Dice* 8 Plastic DIP 8 SO 8 CERDIP**
LB0 GND
___________________Chip Topography
SET
LBI OFF (MAX883/4) STBY (MAX882)
OUT
0.085" (2.159mm)
* Dice are tested at TJ = +25C, DC parameters only. ** Contact factory for availability.
OUT
IN
0.080" (2.032mm)
TRANSISTOR COUNT: 151 NO DIRECT SUBSTRATE CONNECTION. THE N-SUBSTRATE IS INTERNALLY SWITCHED BETWEEN THE MORE POSITIVE OF IN OR OUT.
14
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5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators
________________________________________________________Package Information
E D A3 A A2 E1
DIM A A1 A2 A3 B B1 C D1 E E1 e eA eB L INCHES MAX MIN 0.200 - - 0.015 0.175 0.125 0.080 0.055 0.022 0.016 0.065 0.045 0.012 0.008 0.080 0.005 0.325 0.300 0.310 0.240 - 0.100 - 0.300 0.400 - 0.150 0.115 INCHES MIN MAX 0.348 0.390 0.735 0.765 0.745 0.765 0.885 0.915 1.015 1.045 1.14 1.265 MILLIMETERS MIN MAX - 5.08 0.38 - 3.18 4.45 1.40 2.03 0.41 0.56 1.14 1.65 0.20 0.30 0.13 2.03 7.62 8.26 6.10 7.87 2.54 - 7.62 - - 10.16 2.92 3.81 MILLIMETERS MIN MAX 8.84 9.91 18.67 19.43 18.92 19.43 22.48 23.24 25.78 26.54 28.96 32.13
21-0043A
MAX882/MAX883/MAX884
L A1 e B D1
0 - 15 C B1 eA eB
Plastic DIP PLASTIC DUAL-IN-LINE PACKAGE (0.300 in.)
PKG. DIM PINS P P P P P N D D D D D D 8 14 16 18 20 24
DIM
D A e B
0.101mm 0.004in.
0-8
A1
C
L
A A1 B C E e H L
INCHES MAX MIN 0.069 0.053 0.010 0.004 0.019 0.014 0.010 0.007 0.157 0.150 0.050 0.244 0.228 0.050 0.016
MILLIMETERS MIN MAX 1.35 1.75 0.10 0.25 0.35 0.49 0.19 0.25 3.80 4.00 1.27 5.80 6.20 0.40 1.27
E
H
Narrow SO SMALL-OUTLINE PACKAGE (0.150 in.)
DIM PINS D D D 8 14 16
INCHES MILLIMETERS MIN MAX MIN MAX 0.189 0.197 4.80 5.00 0.337 0.344 8.55 8.75 0.386 0.394 9.80 10.00
21-0041A
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15
5V/3.3V or Adjustable, Low-Dropout, Low IQ, 200mA Linear Regulators MAX882/MAX883/MAX884
___________________________________________Package Information (continued)
DIM INCHES MIN MAX - 0.200 0.014 0.023 0.038 0.065 0.008 0.015 0.220 0.310 0.290 0.320 0.100 0.125 0.200 0.150 - 0.015 0.070 - 0.098 0.005 - MILLIMETERS MIN MAX - 5.08 0.36 0.58 0.97 1.65 0.20 0.38 5.59 7.87 7.37 8.13 2.54 3.18 5.08 3.81 - 0.38 1.78 - 2.49 0.13 -
E1 A D E
Q L e B S1 S B1 L1
0-15 C
A B B1 C E E1 e L L1 Q S S1
CERDIP CERAMIC DUAL-IN-LINE PACKAGE (0.300 in.)
DIM PINS D D D D D D 8 14 16 18 20 24
INCHES MILLIMETERS MIN MAX MIN MAX - 0.405 - 10.29 - 0.785 - 19.94 - 0.840 - 21.34 - 0.960 - 24.38 - 1.060 - 26.92 - 1.280 - 32.51
21-0045A
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
16 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 (c) 1995 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.

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