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LX8221
TM (R)
Dual 150mA CMOS Low Dropout Regulator
PRODUCTION DATA SHEET
DESCRIPTION
KEY FEATURES
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The LX8221 family of dual output linear regulators provide for the selection of either fixed or adjustable output voltages, and combine low dropout operation, fast transient performance, tight output voltage accuracy, and ultra-low ground current within a very small package footprint. The PMOS output transistor allows for an ultra-low dropout characteristic (e.g., typically less than 175mV at 100mA). The individual regulators can be powered from either separate supply voltages or the same supply voltage between 2.8V to 6V allowing for maximum system flexibility. An optional ceramic or tantalum type capacitor may be connected to each Bypass pin separately to improve performance in critical low-noise applications.
Overall regulator efficiency has been improved with a minimized operating ground current (typ < 140A per regulator). Further, this ground current is virtually eliminated in shutdown mode (typ < 1A). Other safety features include channel independent Thermal and Short Circuit Current protection. Separate Enable pins allow each regulator to be switched on and off independently by applying a TTL logic level control signal to the Enable pin further enhancing system level power management. These features combined with a small footprint (i.e., 10-pin MSOP package) make the LX8221 especially useful for battery-operated equipment such as cellular telephones, laptop computers and PDA equipment.
Compact regulators with two 150 mA outputs Dropout Voltage typically 175mV @ 100mA Ultra low shutdown Current typically less than 1A Output trimmed to 0.5% Small MSOP-10 package Over Current & Temperature protection Stable with ceramic or tantalum capacitors APPLICATIONS Battery Operated Systems Laptop, Notebook and PDA's Cellular Telephones/pagers Instrumentation Linear post regulators for SMPS
IMPORTANT: For the most current data, consult MICRO Semi's website: http://www.microsemi.com
PRODUCT HIGHLIGHT
5.0V VIN2 N/C EN1
VIN1 3.3V CB1
EN2
}
To Control Logic On Off
5.0V VIN2
N/C EN1
VIN1 3.3V
EN2
}
To Control Logic On Off
VOUT1
ADJ1
VOUT1
ADJ GND
VOUT2
R1
ADJ2 GND
VOUT2
R1
R2
R2
R1
R2
Fixed / Adjustable Application
Adjustable / Adjustable Application PACKAGE ORDER INFO
LX8221 LX8221
TJ (C) -40 to 125 -40 to 125 -40 to 125 -40 to 125
VOUT1 Adjustable 2.5V 2.7V 3.0V
VOUT2 Adjustable Adjustable Adjustable Adjustable
Plastic MSOP 10-Pin
DU
RoHS Compliant / Pb-free Transition D/C: 0432
Package Marking 8221 AIDU LX 8221 BIDU LX 8221 DIDU LX 8221 GIDU LX
LX8221AIDU LX8221BIDU LX8221DIDU LX8221GIDU
Contact Microsemi for additional / available options
Note: Available in Tape & Reel. Append the letter "T" to the part number. (i.e. LX8221AIDU-TR)
Copyright (c) 2000 Rev. 1.0a, 2005-03-03
Microsemi
Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
LX8221
TM (R)
Dual 150mA CMOS Low Dropout Regulator
PRODUCTION DATA SHEET
ABSOLUTE MAXIMUM RATINGS Input Voltage (VIN1, VIN2) .......................................................................... -0.3V to +7V Output Current (IOUT1, IOUT2)................................................................................. 150mA Operating Temperature Range .....................................................................-40 to +125 C Maximum Junction Temperature (TJ) ...................................................................... 150 C Storage Temperature (TJ) .............................................................................-65 to +150 C Peak Package Solder Reflow Temp. (40 second max. exposure)................. 260C (+0, -5)
Note: Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of specified terminal.
PACKAGE PIN OUT
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VOUT1 CB1 NC EN2 VIN2
1 2 3 4 5
10 9 8 7 6
VIN1 EN1 GND ADJ VOUT2
DU PACKAGE
(Top View) "NC" = No Internal Connection RoHS / Pb-free 100% Matte Tin Lead Finish
THERMAL DATA
FRONT MARKING
DU
Plastic MSOP 8-Pin 206C/W 39C/W 8221 xIDU LX
x = Voltage Combination i.e. A = Adj/Adj
THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA THERMAL RESISTANCE-JUNCTION TO CASE, JC
Junction Temperature Calculation: TJ = TA + (PD x JC). The JA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow. FUNCTIONAL PIN DESCRIPTION PIN NAME VIN1/VIN2 GND EN1/EN2 CB1 VOUT1/VOUT2 ADJ (1, 2) Unregulated input supply voltage Ground Pin Enable control input: Logic high = Enable; logic low or open = Shutdown DESCRIPTION
Reference bypass input. Adding an additional external capacitor reduces output noise. Regulated output voltage. Regulator stability is achieved with external capacitor of 1uF Adjust pin. Connect a resistor divider to this pin to establish preferred output voltage.
PACKAGE DATA PACKAGE DATA
Copyright (c) 2000 Rev. 1.0a, 2005-03-03
Microsemi
Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
LX8221
TM (R)
Dual 150mA CMOS Low Dropout Regulator
PRODUCTION DATA SHEET
BLOCK DIAGRAM
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VIN1
EN1
EN2
VIN2
VOUT1
VOUT2
THERMAL SENSOR
CURRENT LIMIT
CURRENT LIMIT
THERMAL SENSOR
+ CB1 -
CONTROL LOGIC
CONTROL LOGIC
+ -
ADJ
VREF
VREF
GND
RECOMMENDED OPERATING CONDITIONS Parameter
Input Operating Voltage Range (Note 1) Enable Input Voltage Range Continuous Output Current Range Input Capacitor (VIN to GND) Output Capacitor (VOUT to GND)
Symbol
VIN1, VIN2 EN1/2 IOUT1, IOUT1 CIN COUT
Min
2.5
LX8221 Typ
Max
6 VIN + 0.3V
Units
V V mA F F
150 1.0* 1.0* 2.2
Note 1: The minimum VIN has to meet two conditions VIN > 2.5V and VIN > VOUT + VDROPOUT. * Size your output capacitor to meet the transient loading requirement. If you have a very dynamic load, a lower ESR and larger value capacitor will improve the response to these load steps.
ELECTRICAL CHARACTERISTICS Unless otherwise specified, the following specifications apply over the operating ambient temperature -40C TA 125C except where otherwise noted. Test conditions: VIN = VOUT + 0.5V; IOUT =10mA; CIN = 1F; COUT = 1F; TJ = TA using low duty cycle pulse testing methods. LX1742 Parameter Symbol Test Conditions Units Min Typ Max
Output Voltage (2.5, 2.7, 3.0, ADJ) Adjust Reference Voltage Line Regulation VOUT1/2 VADJ VRV VRI TJ = 25C 0mA IOUT1/2 150mA, (VOUT1/2 + 0.5V) VIN 6V TJ = 25C 0mA IOUT1/2 150mA, 2.85V VIN 6V (VOUT1/2 + 0.5V) VIN 6V, IOUT1/2 = 0.1mA TJ = 25C, 0.5mA IOUT1/2 150mA 0.5mA IOUT1/2 100mA ILOAD1/2 = 1mA, VO = -1% ILOAD1/2 = 50mA, VO = -1% ILOAD1/2 = 100mA, VO = -1% ILOAD1/2 = 150mA, VO = -1% EN1 = High, EN2 = High EN1 = Low, EN2 = Low -1 -2.5 1.163 1.140 1 2.5 1.187 1.210 0.15 % V %/V %VNOM
1.175 0.04 0.5
VO VIN VO Load Regulation I O
1.5 0.050 0.175 0.3 0.4 440 1
Dropout Voltage (Note 2)
(VIN
- VO )
VDO IGND ISTBY
Ground Pin Current Copyright (c) 2000 Rev. 1.0a, 2005-03-03
0.175 0.25 280
V
A
Microsemi
Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
LX8221
TM (R)
Dual 150mA CMOS Low Dropout Regulator
PRODUCTION DATA SHEET
Adjust Input Bias Current Enable Pin Current Enable Threshold Short Circuit Current Limit Power Supply Rejection Ratio Output Noise Thermal Shutdown Temperature
IADJ IEN VEN(IH) VEN(IL) IOUT(SC)
PSRR
VADJ = 1.25V VEN1/2 = VIN 2.0
100 100 0.4
nA nA V mA dB V C
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eN TSD
VOUT1 = 0V, VOUT2 = 0V TJ = 25C, f = 120Hz TJ = 25C, COUT = 10uF,CBYPASS = 470 pF
400 50 50 170
Note 2: Dropout voltage is defined as the input to output differential at which the output voltage drops 1% below the nominal value. Dropout voltage specification applies only to output voltages greater than 2.8 V. For output voltages below 2.8 V, the dropout voltage is nothing but the input to output differential, since the minimum input voltage is 2.8 V.
APPLICATIONS
Description The LX8221 family of LDO linear regulators is available in a 10-pin MSOP Package and provides a cost effective power management solution for battery driven applications. The regulator family includes both fixed/adjustable and adjustable/adjustable output voltage versions. The internal PMOS power device provides low dropout regulation with a fast line and load transient response. It also includes internal current limiting and thermal shutdown circuitry. In this section you will find information about capacitor, thermal, and layout design considerations. Input Capacitor To improve load transient response and noise rejection a bypass capacitor is recommended (but it is not required for stability). There are no requirements for the ESR (Equivalent Series Resistor) on the input capacitor, but tolerance and temperature coefficient must be considered when selecting this capacitor to ensure that the capacitor's value will be around 1F over the entire operating temperature range. For the LX8221, a 1F ceramic type capacitor may be connected between both VIN1/2 and ground. Output Capacitor The LX8221 uses an internal feedback loop to maintain a constant output voltage. This feedback loop induces a natural phase shift and the amount of phase shift determines the loop's stability. Therefore, like any lowdropout regulator, an output capacitor with low ESR (Equivalent Series Resistance) is required between VOUT and GND to stabilize the internal control loop. A ceramic,
Copyright (c) 2000 Rev. 1.0a, 2005-03-03
LDO's stability. The LX8221-x adjustable regulator's output voltage can be externally set by connecting the ADJ pin/s to an external resistor divider (See Figure 1 and 2). The output voltage can be calculated using the formula:
R VOUT = VADJ 1 + 1 R2
Enable The Enable pin allows the LX8221 to be independently turned on and off. The Enable pins are compatible with standard TTL-CMOS levels. A logic zero (0.4V) on the En1/ En2 pins shuts the LX8221 off and reduces the supply current to less than 1A (typ). Pulling the Enable inputs high (2.0V) causes normal operation to resume. If the Enable feature is not used, this pin can be connected to VIN. Minimum Load Requirement Although line regulation is improved with a minimum load of 100A, the LX8221 does not have a minimum load current in order to maintain stability. This is an especially important feature in certain applications. Temperature Protection The thermal protection shuts the LX8221 down when the junction temperature exceeds approximately 1500C; there is no appreciable thermal hysteresis. Short Circuit Current Protection The LX8221 includes over-current protection, when the output load current exceeds about 400mA. When this occurs, the protection circuit forces the regulator to decrease
Page 4
Microsemi
Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
LX8221
TM (R)
Dual 150mA CMOS Low Dropout Regulator
PRODUCTION DATA SHEET
tantalum or electrolytic capacitor with a minimum recommended capacitance value of 1.0 F and ESR between 5m and 1 will satisfy the stability for the entire operating range. Optional Bypass Capacitor The fixed/adjustable voltage version of the LX8221 includes a separate Bypass pin (CB1) for the fixed regulator that allows for further reduction of output noise. If the regulator's output noise performance meets system design specifications without the capacitor, omit it. The bypass capacitor impacts the start up time, which is inversely proportional to the size of bypass capacitor. Further, the bypass capacitor reduces the regulator phase margin. Hence, implementing the bypass capacitor will require the use of a larger output capacitor to maintain the
its output current. Thermal Consideration Thermal shutdown protects the integrated circuit from thermal overload caused from a rise in junction temperature during power dissipation. This type of protection is intended for fault protection only and not as a means of current (or, power) limiting during normal application usage. Proper thermal evaluation should be done to ensure that the junction temperature dose not exceed it's maximum rating. Operating at the maximum TJ of 150C can impact reliability. Due to variation in individual device electrical characteristics and thermal resistance, the built in thermal overload protection may be activated at power levels slightly above or below the rated dissipation. Power dissipation for each regulator can
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APPLICATIONS
be calculated using the following equation:
PD = (VIN ( MAX ) - VOUT ( MIN ) )x I OUT ( MAX )
calculate the temperature:
total
power
dissipation
and
junction
Total Power Dissipation:
PD = (4.2V - 2.7 V ) x 0.1A = 0.15 W
(Note: power dissipation resulting from quiescent current is negligible) For the MSOP package, thermal resistance, JA is 2200C/W when mounted on a FR4 copper clad PCB. Junction temperature of the integrated circuit can be calculated using:
TJ = TA + TRISE
Junction Temperature:
TJ = 60o C + (0.15W x 220o C / W ) = 93o C
Layout Consideration: The layout must be implemented with low impedance paths for VIN, VOUT and Ground by creating sufficiently wide traces to avoid voltage drops and pick up noise. Adding an area of PCB copper to the GND pin (pin 8) will reduce the overall JA since it is thermally connected to the device substrate. This will lower the device junction temperature improving overall output voltage accuracy. The input/output capacitors must be placed as close as possible to each voltage regulator output pin.
Where:
TRISE = (PD x JA )
Example: Given the following conditions: TA = 60C VIN= 4.2V VOUT= 2.7V IOUT= 100mA
Copyright (c) 2000 Rev. 1.0a, 2005-03-03
Microsemi
Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
LX8221
TM (R)
Dual 150mA CMOS Low Dropout Regulator
PRODUCTION DATA SHEET
APPLICATION CIRCUITS
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Resistor Table 5.0V VIN2 N/C EN1 R1 = 13.0k R2 = 10.0k
VIN1 3.3V
EN2 3.0V
CB1
VOUT1 2.7V
ADJ GND
VOUT2
R1
R2
Figure 1. Fixed / Adjustable Output Application
5.0V VIN2
N/C EN1
VIN1 3.3V
EN2
Resistor Table VOUT1 R1 = 13.0k R2 = 10.0k VOUT2 R1 = 11.3k R2 = 10.0k 2.7V
ADJ1
VOUT1 2.5V
ADJ2 GND
VOUT2
R1
R2
R1
R2
APPLICATIONS APPLICATIONS APPLICATIONS APPLICATIONS
Figure 2 - Adjustable / Adjustable Output Application
Copyright (c) 2000 Rev. 1.0a, 2005-03-03
Microsemi
Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
LX8221
TM (R)
Dual 150mA CMOS Low Dropout Regulator
PRODUCTION DATA SHEET
OUTPUT VOLTAGE VS TEMPERATURE
DROPOUT VOLTAGE VS TEMPERATURE
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1.185
350 325
1.18
OUTPUT VOLTAGE (V)
300 275
1.175
250 225
IL =150mA
1.17
200 175
1.165
150 125
IL=100mA
1.16
100 75
1.155 -50 -25 0 25 50 75 100 125 TEMPERATURE (C)
50 - 50 - 25 0 25 50 TEMPERATURE ( C) 75 100 125
OUTPUT CURRENT VS SUPPLY VOLTAGE
0
SHORT CIRCUIT CURRENT VS TEMPERATURE
-340 -350
-50
-360 -370
-100
-40C 25C 85C
-380 -390
-150
5V
-400 -410
4V 3V
-200
115C
-250 2.8 3.3 3.8 4.3 4.8 SUPPLY VOLTAGE (V) 5.3 5.8 6.3
-420 -430 - 40 - 25 0 25 85 SUPPLY VOLTAGE ( V) 100 115 125
PSRR VS FREQUENCY
0 0
PSRR VS FREQUENCY IN DROPOUT
50
50
PERFORMANCE
100 0.1 1 Fr equency ( kHz) 10 100
100 0.1 1 Fr equency ( kHz) 10 100
Typical performance characteristics, unless otherwise specified are: CIN = COUT = 1F, CBY = 470pF, VIN = VOUT = 2.5V, TA = 25C, ENABLE is tied to VIN.
Copyright (c) 2000 Rev. 1.0a, 2005-03-03
Microsemi
Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 7
LX8221
TM (R)
Dual 150mA CMOS Low Dropout Regulator
PRODUCTION DATA SHEET
PACKAGE DIMENSIONS
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DU
10-Pin Plastic MSOP
Dim
D
G
B
A B C D F G H J P *LC
J F
MILLIMETERS MIN MAX 2.85 3.05 2.90 3.10 1.10 0.16 0.31 0.40 0.60 0.50 BSC 0.050 0.150 0.10 4.75 5.05 0.10
INCHES MIN MAX 0.112 0.120 0.114 0.122 0.043 0.006 0.0124 0.015 0.023 0.019 BSC 0.002 0.006 0.004 0.187 0.198 0.004
A C H P
*Lead Coplanarity
Note: Dimensions do not include mold flash or protrusions; these shall not exceed 0.155mm(.006") on any side. Lead dimension shall not include solder coverage.
MECHANICALS MECHANICALS
Copyright (c) 2000 Rev. 1.0a, 2005-03-03
Microsemi
Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
LX8221
TM (R)
Dual 150mA CMOS Low Dropout Regulator
PRODUCTION DATA SHEET
NOTES
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NOTES NOTES
PRELIMINARY DATA - Information contained in this document is pre-production data, and is proprietary to Linfinity. It may not be modified in any way without the express written consent of Linfinity. Product referred to herein is not guaranteed to achieve preliminary or production status and product specifications, configurations, and availability may change at any time
Copyright (c) 2000 Rev. 1.0a, 2005-03-03
Microsemi
Linfinity Microelectronics Division 11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
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