View SI91842DT-12-T1_521652.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

Si91842/4
New Product
Vishay Siliconix
150-mA Low-Noise LDO Regulator With Error Flag and Discharge Option
FEATURES
D D D D D D D D D D D D D D Ultra Low Dropout--130 mV at 150-mA Load Low Noise--75 mV(rms) (10-Hz to 100-kHz Bandwidth) Out-of-Regulation Error Flag (power good) Shutdown Control 110-mA Ground Current at 150-mA Load Fast Start-Up (50 mS) 1.5% Guaranteed Output Voltage Accuracy (1.2 V, 2%) 300-mA Peak Output Current Capability Uses Low ESR Ceramic Capacitors Fast Line and Load Transient Response (v 30 ms) 1-mA Maximum Shutdown Current Output Current Limit Reverse Battery Protection Built-in Short Circuit and Thermal Protection D Si91842: Output--Auto-Discharge In Shutdown Mode D Si91844: Output--No-Discharge In Shutdown Mode D Fixed 1.2, 1.8, 2.0, 2.2, 2.5, 2.6, 2.7, 2.8, 2.85, 2.9, 3.0, 3.3, 3.5, 3.6, 5.0-V Output Voltage Options D SOT23-5 Package
APPLICATIONS
D Cellular Phones, Wireless Handsets D Noise-Sensitive Electronic Systems, Laptop and Palmtop Computers D PDAs D Pagers D Digital Cameras D MP3 Player D Wireless Modem
DESCRIPTION
The Si91842/4 is a 150-mA CMOS LDO (low dropout) voltage regulator. It is the perfect choice for low voltage, low power applications. An ultra low ground current and ultra fast turn-on make this part attractive for battery operated power systems. The Si91842/4 also offers ultra low dropout voltage to prolong battery life in portable electronics. Systems requiring a quiet voltage source will benefit from the Si91842/4's low output noise. The Si91842/4 is designed to maintain regulation while delivering 300-mA peak current, making it ideal for systems that have a high surge current upon turn-on. For better transient response and regulation, an active pull-down circuit is built into the Si91842/4 to clamp the output voltage when it rises beyond normal regulation. The Si91842 automatically discharges the output voltage by connecting the output to ground through a 100-W n-channel MOSFET when the device is put in shutdown mode.
The Si91842/4 features reverse battery protection to limit reverse current flow to approximately 1-mA in the event reversed battery is applied at the input, thus preventing damage to the IC.
TYPICAL APPLICATION CIRCUIT
Si91842/4
VIN 1 mF 2 GND 5 51 kW 1 VIN VOUT 5 VOUT 1 mF
SD
3
SD
ERROR
4
ERROR
SOT-23, 5-Lead
Document Number: 71732 S-20478--Rev. C, 01-Apr-02
www.vishay.com
1
Si91842/4
Vishay Siliconix
ABSOLUTE MAXIMUM RATINGS
Absolute Maximum Ratings Input Voltage, VIN to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -6.0 to 6.5 V VERROR, VSD (See Detailed Description) . . . . . . . . . . . . . . . . . . . . . . . -0.3 V to VIN Output Current, IOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Short Circuit Protected Output Voltage, VOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3 V to VIN + 0.3 V Package Power Dissipation, (Pd)b . . . . . . . . . . . . . . . . . . . . . . . . . . . 440 mW Package Thermal Resistance, (qJA)a . . . . . . . . . . . . . . . . . . . . . . . . . 180_C/W Maximum Junction Temperature, TJ(max) . . . . . . . . . . . . . . . . . . . . . . . 150_C Storage Temperature, TSTG . . . . . . . . . . . . . . . . . . . . . . . . . . -65_C to 150_C Notes a. Device mounted with all leads soldered or welded to PC board. b. Derate 5.5 mW/_C above TA = 70_C
New Product
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.
RECOMMENDED OPERATING RANGE
Input Voltage, VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 V to 6 V Input Voltage, VSD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 V to VIN CIN = COUT = 1 mF (ceramic) Maximum ESR of COUT: 0.4 W Operating Ambient Temperature, TA . . . . . . . . . . . . . . . . . . . . -40_C to 85_C
SPECIFICATIONS
Test Conditions Unless Specified Parameter
Input Voltage Range
Limits
-40 to 85_C
Symbol
VIN
TA = 25_C, VIN = VOUT(nom) + 1 V, IOUT = 1 mA, _ CIN = 1 mF, COUT = 1.0 mF, VSD = 1.5 V
Tempa
Full
Minb
2 -1.5 -2.5 -2.0 -3.0 -0.06 0 0
Typc
Maxb
6
Unit
V
VOUT w 1.8 V Output Voltage Accuracy 1 mA v IOUT v 150 mA VOUT = 1.2 V Line Regulation (VOUT v 3 V) Line Regulation (3.0 V < VOUT v3.6 V) Line Regulation (5-V Version) DVOUT DVIN 100 From VIN = VOUT(nom) + 1 V to VOUT(nom) + 2 V
Room Full Room Full Full Full
1 1 1 1
1.5 2.5 2.0 3.0 0.18 0.3 0.4 %/V %
VOUT(nom) From VIN = 5.5 V to 6 V IOUT = 1 mA
Full Room Room Full Room Full Room
1 45 50 130 65 190 100 110 110 120 300 75 80 90 180 220 100 120 250 300 150 180 200 230 170 200 200 230 mA mV(rms) mA m mV
Dropout Voltaged, g (VOUT(nom) w 2.6 V) VIN - VOUT Dropout Voltaged, g (VOUT(nom) t 2.6 V, VIN w 2 V)
IOUT = 50 mA IOUT = 150 mA IOUT = 50 mA IOUT = 150 mA IOUT = 0 mA IOUT = 150 mA IGND IOUT = 0 mA IOUT = 150 mA
Full Room Full Room Full Room Full Room Full Room Full Full Room
Ground Pin Currente, g (VOUT(nom) v 3 V)
Ground Pin Currente, g (VOUT(nom) u 3 V) Peak Output current Output Noise Voltage IO(peak) eN
VOUT w 0.95 x VOUT(nom). tPW = 2 ms VOUT = 2.6 V, BW = 10 Hz to 100 kHz, 0 mA t IOUT t 150 mA
www.vishay.com
2
Document Number: 71732 S-20478--Rev. C, 01-Apr-02
Si91842/4
New Product
SPECIFICATIONS
Test Conditions Unless Specified Parameter Symbol
TA = 25_C, VIN = VOUT(nom) + 1 V, IOUT = 1 mA, CIN = 1 mF, COUT = 1.0 mF, VSD = 1.5 V
Vishay Siliconix
Limits
-40 to 85_C
Tempa
Room Room Room Room Room Room Room
Minb
Typc
60 40 30 20
Maxb
Unit
f = 1 kHz Ripple Rejection DVOUT/DVIN IOUT = 150 mA f = 10 kHz f = 100 kHz Dynamic Line Regulation Dynamic Load Regulation Thermal Shutdown Junction Temperature Thermal Hysteresis Reverse current Short Circuit Current DVO(line) DVO(load) TJ(S/D) THYST IR ISC VIN = -6.0 V VOUT = 0 V VIN : VOUT(nom) + 1 V to VOUT(nom) + 2 V tr/tf = 2 ms, IOUT = 150 mA IOUT : 1 mA to 150 mA, tr/tf = 2 ms
dB
mV 25 150 20 1 700 mA mA _C C
Room Room
Shutdown
Shutdown Supply Current SD Pin Input Voltage Auto Discharge Resistance SD Pin Input Currentf SD Hysteresis VOUT Turn-On Time ICC(off) VSD R_DIS IIN(SD) VHYST(SD) tON VSD (See Figure 1), ILOAD = 100 mA VSD = 0 V High = Regulator ON (Rising) Low = Regulator OFF (Falling) Si91842 Only VSD = 1.5 V, VIN = 6 V Room Full Full Room Room Full Room 100 0.7 150 50 1.5 0.1 1 VIN 0.4 mA V W mA mV mS
ERROR Output
ERROR High Leakage ERROR Low Voltage ERROR Voltage Threshold ERROR Voltage Threshold Hysteresis IOFF VOL VERROR VHYST(ERROR) ERROR v VIN. VOUT in Regulation ISINK = 0.5 mA VOUT Below VOUT(nom)g, VIN w 2 V VOUT Falling, IOUT = 1 mA, VOUT(nom) w 2 V VOUT(nom)g t 2 V, VIN u 2 V Full Full Full Full Room -2 -4 -4 1.5 1 0.4 -6 % mA V
Notes a. Room = 25_C, Full = -40 to 85_C. b. The algebraic convention whereby the most negative value is a minimum and the most positive a maximum. c. Typical values are for DESIGN AID ONLY, not guaranteed nor subject to production testing. d. Dropout voltage is defined as the input to output differential voltage at which the output voltage drops 2% below the output voltage measured with a 1-V differential, provided that VIN does not not drop below 2.0 V. e. Ground current is specified for normal operation as well as "drop-out" operation. f. The device's shutdown pin includes a typical 2-MW internal pull-down resistor connected to ground. g. VOUT(nom) is VOUT when measured with a 1-V differential to VIN.
TIMING WAVEFORMS
VIN VSD tr v 1 mS
0V
tON VNOM 0.95 VNOM
VOUT
FIGURE 1. Timing Diagram for Power-Up
Document Number: 71732 S-20478--Rev. C, 01-Apr-02
www.vishay.com
3
Si91842/4
Vishay Siliconix
PIN CONFIGURATION
New Product
SOT-23, 5-Lead
VIN 1 5 VOUT
GND
2
SD
3
4
ERROR
PIN DESCRIPTION
Pin Number
1 2 3 4 5
Name
VIN GND SD ERROR VOUT
Function
Input supply pin. Bypass this pin with a 1-mF ceramic or tantalum capacitor to ground Ground pin. For better thermal capability, directly connected to large ground plane By applying less than 0.4 V to this pin, the device will be turned off. Connect this pin to VIN if unused The open drain output is an error flag output which goes low when VOUT drops 4% below its nominal voltage. Output voltage. Connect COUT between this pin and ground.
ORDERING INFORMATION
Si91842 Part Number
SI91842DT-12-T1b Si91842DT-18-T1 Si91842DT-20-T1 Si91842DT-22-T1 Si91842DT-25-T1 Si91842DT-26-T1 Si91842DT-27-T1 Si91842DT-28-T1 Si91842DT-285-T1 Si91842DT-29-T1 Si91842DT-30-T1 Si91842DT-33-T1 Si91842DT-35-T1 Si91842DT-36-T1 Si91842DT-50-T1
Si91844 Temp. Range Pkg. Part Number
Si91844DT-18-T1 Si91844DT-20-T1 Si91844DT-22-T1 Si91844DT-25-T1 Si91844DT-26-T1 Si91844DT-27-T1 Si91844DT-28-T1 -40 to 85_C SOT23-5 Si91844DT-285-T1 Si91844DT-29-T1 Si91844DT-30-T1 Si91844DT-33-T1 Si91844DT-35-T1 Si91844DT-36-T1 Si91844DT-50-T1
Marking
J8LLL C8LLL C9LLL C0LLL D1LLL D2LLL D3LLL D4LLL D5LLL D6LLL D7LLL D8LLL D9LLL D0LLL E1LLL
Voltage
1.2 1.8 2.0 2.2 2.5 2.6 2.7 2.8 2.85 2.9 3.0 3.3 3.5 3.6 5.0
Marking
F6LLL F7LLL F8LLL F9LLL F0LLL G1LLL G2LLL G3LLL G4LLL G5LLL G6LLL G7LLL G8LLL G9LLL
Voltage
1.8 2.0 2.2 2.5 2.6 2.7 2.8 2.85 2.9 3.0 3.3 3.5 3.6 5.0
Temp. Range
Pkg.
-40 to 85_C _
SOT23-5
Notes: a. LLL = Lot Code b. Advanced Information, available March 2002. www.vishay.com Document Number: 71732 S-20478--Rev. C, 01-Apr-02
4
Si91842/4
New Product
Vishay Siliconix
TYPICAL CHARACTERISTICS (INTERNALLY REGULATED, 25_C UNLESS NOTED)
Normalized Output Voltage vs. Load Current
0.30 VIN = VOUT(nom) + 1 V 0.15 0.00 -0.15 -0.30 -0.45 -0.60 -0.75 0 25 50 75 100 125 150 Load Current (mA) V OUT (%) 0.2 IOUT = 0 mA Output Voltage (%) -0.0 IOUT = 75 mA -0.2 -0.4 -0.6 -0.8 -1.0 -40 IOUT = 150 mA 0.4 VIN = VOUT(nom) + 1 V
Normalized VOUT vs. Temperature
-15
10
35
60
85
Ambient Temperature (_C)
GND Current vs. Load Current
150 VOUT = 3.0 V VIN = 4.0 V 125 25_C I GND ( mA) I GND ( mA) 200 85_C 300
No Load GND Pin Current vs. Input Voltage
250
100 -40_C
150 85_C 25_C 100 -40_C
75 50
50 0 25 50 75 100 125 150 Load Current (mA)
0 2 3 4 5 6 7 Input Voltage (V)
Power Supply Rejection
0 CIN = 1 mF COUT = 1 mF ILOAD = 150 mA VOUT = 3.0 V I SC (mA) 750
Output Short Circuit Current vs. Temperature
VOUT = 2.6 V 725
-20
700 Gain (dB)
-40
675
650 -60 625
-80 10 100 1000 10000 100000 1000000 Frequency (Hz)
600 -40
-15
10
35
60
85
AmbientTemperature (_C)
Document Number: 71732 S-20478--Rev. C, 01-Apr-02
www.vishay.com
5
Si91842/4
Vishay Siliconix
New Product
TYPICAL CHARACTERISTICS (INTERNALLY REGULATED, 25_C UNLESS NOTED)
Dropout Voltage vs. Load Current
350 VOUT = 3.0 V 300 250 V DROP (mV) 2.0 200 150 100 50 0 0 60 120 180 240 300 ILOAD (mA) 0.5 V OUT (V) 2.5 3.0 VOUT = 3.0 V
VIN - VOUT Transfer Characteristic
1.5
1.0
0.0 0 1 2 3 VIN (V) 4 5 6
Dropout Voltage vs. Temperature
350 VOUT = 3.0 V 300 IOUT = 300 mA Dropout Voltage (mV) 250 V DROP (mV) 200 150 100 50 0 -50 IOUT = 10 mA IOUT = 0 mA -25 0 25 50 75 100 125 150 Junction Temperature (_C) IOUT = 150 mA 300 250 200 150 350 400
Dropout Voltage vs. VOUT
IOUT = 300 mA
IOUT = 75 mA 100 50 0 1.0
IOUT = 150 mA
IOUT = 75 mA
IOUT = 10 mA 1.5 2.0 2.5 3.0 VOUT 3.5 4.0 4.5 5.0
www.vishay.com
6
Document Number: 71732 S-20478--Rev. C, 01-Apr-02
Si91842/4
New Product
TYPICAL WAVEFORMS
Vishay Siliconix
Load Transient Response-1
Load Transient Response-2
VOUT 10 mV/div VOUT 10 mV/div
ILOAD 100 mA/div
ILOAD 100 mA/div
20 ms/div VOUT = 3.0 V COUT = 1 mF ILOAD = 1 to 150 mA trise = 2 msec
20 ms/div VOUT = 3.0 V COUT = 1 mF ILOAD = 150 to 1 mA tfall = 2 msec
LineTransient Response-1
LineTransient Respons-2
VOUT 10 mV/div VOUT 10 mV/div
VIN 2 V/div
VIN 2 V/div
20 ms/div VINSTEP = 4 to 5 V VOUT = 3 V COUT = 1 mF CIN = 1 mF ILOAD = 150 mA trise = 5 msec
20 ms/div VINSTEP = 5 to 4 V VOUT = 3 V COUT = 1 mF CIN = 1 mF ILOAD = 150 mA tfall = 5 msec
Document Number: 71732 S-20478--Rev. C, 01-Apr-02
www.vishay.com
7
Si91842/4
Vishay Siliconix
TYPICAL WAVEFORMS
New Product
Output Noise
10
Noise Spectrum
VOUT 200 mV/div
Output Spectral Noise Density
mV
Hz
0.01 4 ms/div VIN = 4 V VOUT = 3 V IOUT = 150 mA BW = 10 Hz to 100 kHz 10 Hz VIN = 4 V VOUT = 3 V ILOAD = 150 mA 1 MHz
www.vishay.com
8
Document Number: 71732 S-20478--Rev. C, 01-Apr-02
Si91842/4
New Product
BLOCK DIAGRAM
Vishay Siliconix
Si91842/4
VIN Reverse Polarity Protection
Reference
- +
VOUT Thermal Sensor Si91842 Only
Current Limit ERROR SD Shutdown Control
GND
DETAILED DESCRIPTION
The Si91842/4 is a low-noise, low drop-out and low quiescent current linear voltage regulator, packaged in a small footprint SOT23-5 package. The Si91842/4 can supply loads up to 300 mA. As shown in the block diagram, the circuit consists of a bandgap reference, error amplifier, p-channel pass transistor and feedback resistor string. Additional blocks, not shown in the block diagram, include a precise current limiter, reverse battery and current protection, and thermal sensor. protection is desired. Hardwiring the SD pin directly to the VIN pin is allowed when reverse battery protection is not desired. ERROR ERROR is an open drain output that goes low when VOUT is less than 4% of its normal value. To obtain a logic level output, connect a pull-up resister from ERROR to VOUT or any other voltage equal to or less than VIN. ERROR pin is high impedance (off) when SD pin is low. Auto-Discharge/No-Discharge VOUT has an internal 100-W (typ.) discharge path to ground when SD pin is low for the Si91842. the Si91844 does not have a discharge path when the SD pin is low. Stability The circuit is stable with only a small output capacitor equal to 6 nF/mA (= 1 mF @ 150 mA). Since the bandwidth of the error amplifier is around 1-3 MHz and the dominant pole is at the output node, the capacitor should be capacitive in this range, i.e., for 150-mA load current, an ESR <0.4 W is necessary. Parasitic inductance of about 10 nH can be tolerated.
Thermal Overload Protection The thermal overload protection limits the total power dissipation and protects the device from being damaged. When the junction temperature exceeds 150_, the device turns the p-channel pass transistor off.
Reverse Battery Protection The Si91842/4 has a battery reverse protection circuitry that disconnects the internal circuitry when VIN drops below the GND voltage. There is no current drawn in such an event. When the SD pin is hardwired to VIN, the user must connect the SD pin to VIN via a 100-kW resistor if reverse battery
Document Number: 71732 S-20478--Rev. C, 01-Apr-02
www.vishay.com
9

▲Up To Search▲

Price & Availability of SI91842DT-12-T1

	To Download SI91842DT-12-T1 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .