100mA Low Dropout Voltage Regulators CORPORATION LP2950 / LP2951 PRODUCT DESCRIPTION FEATURES * 5V, 3.3V, and 3.0V Versions at 100mA Output * Very Low Quiescent Current Dropout Voltage * Low * Extremely Tight Load and Line Regulation * Very Low Temperature Coefficient and Thermal Limiting * Current * Needs Only 1F for Stability The Calogic LP2950 and LP2951 are low power voltage regulators. These devices are an excellent choice for use in battery-powered applications such as cordless telephones, radio control systems, and portable computers. The LP2950 and LP2951 features very low quiescent current and very low dropout voltage (Typ. 50mV at light load and 380mV at 100mA). This includes a tight initial tolerance of 0.5% typ., extremely good load and line regulation 0.05% typ. and very low output temperature coefficient, making the LP2950/LP2951 useful as a low-power voltage reference. LP2951 Versions Only Error Flag Warns of Output Dropout Logic-Controlled Electronic Shutdown Output Programmable from 1.24 to 29V * * * The error flag output feature is used as power-on reset for warning of a low output voltage, due to falling voltage input of batteries. Another feature is the logic-compatible shutdown input which enables the regulator to be switched on and off. The LP2950 is offered in a 3-pin TO-92 package compatible with other 5V, 3.0V, 3.3V regulators. The LP2951 is also available in 8-pin plastic and SO-8. APPLICATIONS * Battery Powered Systems * Cordless Telephones Control Systems * Radio * Portable / Palm Top / Notebook Computers * Portable Consumer Equipment Instrumentation * Portable * Avionics * SMPS Post-Regulator Reference * Voltage * Automotive Electronics The regulator output voltage may be pin-strapped for 5V, 3V or 3.3 volts or programmed from 1.24 volt to 29 volts with an external pair of resistors. Use of AS's design, processing and testing techniques make our LP2950 and LP2951 superior over similar products. ORDERING INFORMATION PART PACKAGE LP2950ACN-X LP2950CN-X LP2951ACP-X LP2951CP-X LP2951ACS-X LP2951CS-X TO-92 (3-Pin) TO-92 (3-Pin) Plastic DIP (8-Pin) Plastic DIP (8-Pin) Plastic SOIC (8-Pin) Plastic SOIC (8-Pin) TEMPERATURE RANGE IND. IND. IND. IND. IND. IND. X = 3.0V, 3.3V or 5.0V PIN CONNECTIONS 8-PIN SURFACE MOUNT TO-92 OUTPUT 1 8 INPUT SENSE 2 7 FEEDBACK SHUTDOWN 3 6 5V OR 3.3V TAP GROUND 4 5 ERROR 1 2 3 LP2951 BOTTOM VIEW TOP VIEW 1. OUTPUT 2. GROUND 3. INPUT 1D-20 1D-19 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 LP2950 / LP2951 CORPORATION ABSOLUTE MAXIMUM RATINGS Power Dissipation . . . . . . . . . . . . . . . . . . . . . Internally Limited Lead Temp. (Soldering, 5 Seconds) . . . . . . . . . . . . . . . 260 oC Storage Temperature Range . . . . . . . . . . . . . . . -65 to +150oC Operating Junction Temperature Range LP2951. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to +150oC LP2950AC/LP2950C LP2951AC/LP2951C . . . . . . . . . . . . . . . . . . . -40 to +125oC Input Supply Voltage . . . . . . . . . . . . . . . . . . . . . . -0.3 to +30V Feedback Input Voltage . . . . . . . . . . . . . . . . . . . . -1.5 to +30V Shutdown Input Voltage. . . . . . . . . . . . . . . . . . . . -0.3 to +30V Error Comparator Output . . . . . . . . . . . . . . . . . . . -0.3 to +30V ESD Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2KV Min ELECTRICAL CHARACTERISTICS: VS = 15V, TA = 25oC, unless otherwise specified. PARAMETER LP2951 LP2950AC / LP2951AC LP2950C / LP2951C CONDITIONS (Note 2) UNITS MIN TYP MAX MIN TYP MAX MIN TYP MAX 2.985 3.0 3.015 3.036 2.985 2.970 2.964 3.0 3.0 3.0 3.015 3.030 3.036 2.970 2.955 2.940 3.0 3.0 3.0 3.030 3.045 3.060 V V V TJ = 25oC -25oC TJ 85oC Full Operating Temperature 3V VERSIONS Output Voltage 2.964 Output Voltage 2.955 3.0 3.045 2.958 3.0 3.042 2.928 3.0 3.072 V 100A IL 100mA TJ TJMAX 3.284 3.3 3.317 3.340 3.284 3.267 3.260 3.3 3.3 3.3 3.317 3.333 3.340 3.267 3.251 3.234 3.3 3.3 3.3 3.333 3.350 3.366 V V V TJ = 25oC -25oC TJ 85oC Full Operating Temperature 3.3V VERSIONS Output Voltage 3.260 3.251 3.3 3.350 3.254 3.3 3.346 3.221 3.3 3.379 V 100A IL 100mA TJ TJMAX 4.975 5.0 5.025 5.06 4.975 4.95 4.94 5.0 5.0 5.0 5.025 5.050 5.06 4.95 4.925 4.90 5.0 5.0 5.0 5.05 5.075 5.10 V V V TJ = 25oC -25oC TJ 85oC Full Operating Temperature 5.0 5.075 4.93 5.0 5.07 4.88 5.0 5.12 V 100A IL 100mA TJ TJMAX Output Voltage Temperature Coefficient 20 120 20 Output Voltage 5V VERSIONS Output Voltage 4.94 Output Voltage 4.925 ALL VOLTAGE OPTIONS ppm/oC 50 (Note 1) Line Regulation (Note 3) 0.03 0.1 0.03 0.1 0.04 0.2 % 6V VIN 30V (Note 4) Load Regulation (Note 3) 0.04 0.1 0.04 0.1 0.1 0.2 % 100A IL 100mA Dropout Voltage (Note 5) 50 380 80 450 50 380 80 450 50 380 80 450 mV mV IL = 100A IL = 100mA Ground Current 150 8 170 12 150 8 170 12 150 8 170 12 A mA IL = 100A IL = 100mA Current Limit 130 200 130 200 130 200 mA VOUT = 0 Thermal Regulation 0.05 0.2 0.05 0.2 0.05 0.2 %/W Output Noise, 10Hz to 100KHz 430 160 100 430 160 100 430 160 100 LP2951 LP2951AC LP2951C 8-PIN VERSIONS ONLY Reference Voltage 1.22 Reference Voltage 1.19 1.235 1.25 1.22 1.27 1.19 60 1.235 40 1.25 1.21 1.27 1.185 60 1.235 40 Vrms Vrms Vrms 1.26 CL = 1F CL = 200F CL = 13.3F (Bypass = 0.01F pins 7 to 1 (LP2951)) V 1.285 V 60 nA Feedback Pin Bias Current 40 Reference Voltage Temperature Coefficient 20 20 50 ppm/oC Feedback Pin Bias Current Temperature Coefficient 0.1 0.1 0.1 nA/oC Over Temperature (Note 6) (Note 7) CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 LP2950 / LP2951 CORPORATION ELECTRICAL CHARACTERISTICS (continued) PARAMETER LP2951 TYP MAX MIN ERROR COMPARATOR Output Leakage Current Output Low Voltage Upper Threshold Voltage Lower Threshold Voltage Hysteresis SHUTDOWN INPUT 40 Input Logic Voltage 0.01 150 60 75 15 1 250 1.3 0.6 LP2950AC / LP2951AC LP2950C / LP2951C MIN TYP MAX MIN TYP MAX 40 95 0.01 150 60 75 15 1 250 1.3 0.7 40 95 1 250 1.3 0.7 95 A mV mV mV mV VOH = 30V VIN = 4.5V, IOL = 400A (Note 7) (Note 7) (Note 7) Low (Regulator ON) High (Regulator OFF) VS = 2.4V VS = 30V (Note 9) 30 675 50 800 30 675 50 800 30 675 50 800 V V A A 3 10 3 10 3 10 A 2 2 Shutdown Pin Input Current Regulator Output Current in Shutdown 0.01 150 60 75 15 2 CONDITIONS (Note 2) UNITS Note 1: Output or reference voltage temperature coefficients defined as the worst case voltage change divided by the total temperature range. Note 2: Unless otherwise specified all limits guaranteed for TJ = 25oC, VIN = 6V, I L=100A and CL = 1F. Additional conditions for the 8-pin versions are feedback tied to 5V tap and output tied to output Sense (VOUT = 5V) and VSHUTDOWN 0.8V. Note 3: Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are covered under the specification for thermal regulation. Note 4: Line regulation for the LP2951 is tested at 150 oC for IL = 1mA. For I L = 100A and TJ = 125 oC, line regulation is guaranteed by design to 0.2%. See typical performance characteristics for line regulation versus temperature and load current. Note 5: Dropout voltage is defined as the input to output differential at which the output voltage drops 100mV below its nominal value measured at 1V differential at very low values of programmed output voltage, the minimum input supply voltage of 2V (2.3V over temperature) must be taken input account. Note 6: VREF VOUT (VIN - 1V), 2.3 VIN 30V, 100A I L 100mA, TJ T JMAX. Note 7: Comparator thresholds are expressed in terms of a voltage differential at the feedback terminal below the nominal reference voltage measured at 6V input. To express these thresholds in terms of output voltage change, multiply by the error amplifier gain = V OUT/VREF = (R1+R2)/R2. For example, at a programmed output voltage of 5V, the error output is guaranteed to go low when the output drops by 95mV x 5V/1.235 = 384mV. Thresholds remain constant as a percent of VOUT as VOUT is varied, with the dropout warning occurring at typically 5% below nominal, 7.5% guaranteed. Note 8: VSHUTDOWN 2V, VIN 30V, VOUT = 0, Feedback pin tied to 5V Tap. Note 9: All typical values are not guaranteed. BLOCK DIAGRAM UNREGULATED DC 7 + 8 FEEDBACK 5V @ 100mA MAX 1 INPUT OUTPUT 2 SENSE + - 3 FROM CMOS OR TTL ERROR AMPLIFIER 180k 6 SHUTDOWN 60k + 5 + 1F + 60mV - + 330k 5V TAP 1.23V ERROR DETECTION COMPARATOR ERROR 4 TO CMOS OR TTL REFERENCE GROUND LP2950 AND LP2951 BLOCK DIAGRAM 1D-21 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 LP2950 / LP2951 CORPORATION APPLICATION HINTS EXTERNAL CAPACITORS * The stability of the LP2950/LP2951 requires a 1.0F or greater capacitor between output and ground. Oscillation could occur without this capacitor. Most types of tantalum or aluminum electrolytic are acceptable. For operations below -25oC a solid tantalum is recommended since the many aluminum types have electrolytes that freeze at about -30oC. The ESR of about 5 or less and resonant frequency about 500kHz are the most important parameters in the value of the capacitor. The capacitors value may be increased without limit. The error comparator has an open-collector output which requires an external pullup resistor. Depending on the system requirements the resistor may be returned to 5V output or other supply voltage. In determining the value of this resistor, note that the output is rated to sink 400A, this value adds to battery drain in a low battery condition. Suggested values range from 100K to 1M. If the output is unused this resistor is not required. * At lower values of output current, less output capacitance is The LP2951 may be pin-strapped for 5V using its internal voltage divider by tying Pin 1 (output) to Pin 2 (sense) and Pin 7 (feedback) to Pin 6 (5V Tap). Also, it may be programmed for any output voltage between its 1.235V reference and its 30V maximum rating. As seen in Figure 2, an external pair of resistors is required. required for stability. For currents below 10mA the value of the capacitor can be reduced to 0.33F and 0.1F for 1mA. More output capacitance is needed for the 8-pin version at voltages below 5V since it runs the error amplifier at lower gain. * At worst case 3.3F or greater must be used for the condition of 100mA load at 1.23V output. * The LP2950, unlike other low dropout regulators will remain stable and in regulation with no load in addition to the internal voltage divider. This feature is especially important in applications like CMOS RAM keep-alive circuits. When setting the output voltage of the LP2951 version with external resistors, a minimum load of 1A is recommended. * If there is more than 10 inches of wire between the input and the AC filter capacitor or if a battery is used as the input then a 1A tantalum or aluminum electrolytic capacitor should be placed from the input to the ground. PROGRAMMING THE OUTPUT VOLTAGE OF LP2951 Refer to the equation below for the programming of the output voltage: VOUT = VREF x (1 + R1\R2) + IFBR1 The VREF is 1.235 and IFB is the feedback bias current, nominally -20nA. The minimum recommended load current of 1A forces an upper limit of 1.2M on value of R2. If no load is presented the IFB produces an error of typically 2% in VOUT which may be eliminated at room temperature by trimming R1. To improve the accuracy choose the value of R2 = 100k this reduces the error by 0.17% and increases the resistor program current by 12A. Since the LP2951 typically draws 60A at no load with Pin 2 open-circuited this is a small price to pay. * Instability REDUCING OUTPUT NOISE ERROR DETECTION COMPARATOR OUTPUT It may be an advantage to reduce the AC noise present at the output. One way is to reduce the regulator bandwidth by increasing the size of the output capacitor. This is the only way that noise can be reduced on the lead 3 of LP2950, but is relatively inefficient, as increasing the capacitor from 1F to 220F only decreases the noise from 430V to 160Vrms for a 100kHz bandwidth at 5V output. can occur if there is a stray capacitance to the LP2951 feedback terminal (pin 7). This could cause more problems when using a higher value of external resistors to set the output voltage. This problem can be eliminated by adding a 100pF capacitor between output and feedback and increasing the output capacitor to at least 3.3F. The Comparator produces a logic low output whenever the LP2951 output falls out of regulation by more than around 5%. This occurs at approximately 60mV offset divided by the 1.235 reference voltage. This trip level remains 5% below normal regardless of the programmed output voltage of the regulator. Figure 1 shows the timing diagram depicting the ERROR signal and the regulator output voltage as the LP2951 input is ramped up and down. The ERROR signal becomes low at around 1.3V input, and goes high around 5V input (input voltage at which VOUT = 4.75). Since the LP2951's dropout voltage is load dependent, the input voltage trip point (around 5V) will vary with the load current. The output voltage trip point (approx. 4.75V) does not vary with load. Noise could also be reduced fourfold by a bypass capacitor across R1, since it reduces the high frequency gain from 4 to unity. CBYPASS 1/2R1 x 200Hz or choose 0.01F. When doing this, the output capacitor must be increased to 3.3F to maintain stability. These changes reduce the output noise from 430V to 100Vrms for a 100kHz bandwidth at 5V output. With the bypass capacitor added, noise no longer scales with output voltage so that improvements are more dramatic at higher voltages. CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 LP2950 / LP2951 CORPORATION TYPICAL PERFORMANCE CHARACTERISTICS OUTPUT VOLTAGE (VOLTS) 0.1 4 RL = 50k 3 RL = 50 2 1 200 RL = 50k 175 150 125 RL = 100 75 50 25 1D-22 5.06 OUTPUT VOLTAGE (V) 120 5V OUTPUT 110 RL = 50 100 90 80 70 60 50 40 30 20 10 0 0 1 2 3 4 5 6 7 8 9 10 INPUT VOLTAGE (VOLTS) 1D-25 170 150 140 130 120 110 QUIESCENT CURRENT 80 VIN = 6V IL = 100A 70 60 50 -75 -50 -25 0 25 50 75 100 125 150 TEMPERATURE (C) 1D-31 5.02 5.0 4.98 0.2% IL = 100mA 300 100 IL = 100A 50 10 IL = 100mA 8 7 -75 -50 -25 0 25 50 75 100 125 150 TEMPERATURE (C) 1D-32 120 100 IL = 1mA 80 IL = 0 60 40 20 1 2 3 4 5 6 7 INPUT VOLTAGE (VOLTS) 8 1D-27 DROPOUT VOLTAGE 500 400 300 200 TJ = 25C 100 0 100A QUIESCENT CURRENT VIN = 6V 140 0 1mA 10mA OUTPUT CURRENT 100mA 1D-30 QUIESCENT CURRENT 8 5V OUTPUT 9 5V OUTPUT 0 DROPOUT VOLTAGE 500 QUIESCENT CURRENT 160 5V OUTPUT 0 -75 -50 -25 0 25 50 75 100 125 150 TEMPERATURE (C) 1D-29 QUIESCENT CURRENT (mA) 90 OUTPUT VOLTAGE vs TEMPERATURE OF 3 REPRESENTATIVE UNITS 400 2 3 4 5 6 7 8 9 10 INPUT VOLTAGE (VOLTS) 1D-24 1 1D-23 5.04 600 5V OUTPUT 100 0 6 4.94 -75 -50 -25 0 25 50 75 100 125 150 TEMPERATURE (C) 1D-26 100 -75 -50 -25 0 25 50 75 100 125 150 TEMPERATURE (C) 1D-28 110 1 2 3 4 5 INPUT VOLTAGE (VOLTS) 4.96 SHORT CIRCUIT CURRENT 160 120 0 0 QUIESCENT CURRENT (A) 100 DROPOUT VOLTAGE (mV) 1.0 10 LOAD CURRENT (mA) DROPOUT VOLTAGE (mV) INPUT CURRENT (mA) 5V OUTPUT 225 5 0 INPUT CURRENT SHORT CIRCUIT CURRENT (mA) INPUT CURRENT 250 5V OUTPUT QUIESCENT CURRENT (mA) GROUND PIN CURRENT (mA) 1 0.01 0.1 QUIESCENT CURRENT (A) DROPOUT CHARACTERISTICS 6 INPUT CURRENT (A) QUIESCENT CURRENT 10 5V OUTPUT 7 6 5 IL = 100mA 4 3 2 1 0 0 1 2 3 4 5 6 INPUT VOLTAGE (V) 7 8 1D-33 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 LP2950 / LP2951 CORPORATION LP2951 MINIMUM OPERATING VOLTAGE 2.1 1.9 1.8 -50 TA = 125C -100 -150 TA = 25C -200 -30 -75 -50 -25 0 25 50 75 100 125 150 TEMPERATURE (C) 1D-35 LP2951 COMPARATOR SINK CURRENT 2.5 VOUT = 5V HYSTERESIS 2 1.5 TA = 25C TA = -55C 0 0.5 NOTE: PULLUP RESISTOR TO SEPARATE 5V SUPPLY 5 IO = 1mA IO = 100mA 0.5 0.2 VOUT = 5V 0.1 CL = 1A 0.05 RIPPLE REJECTION 90 70 IL = 0 50 IL = 100A 40 CL = 1F 30 VIN = 6V 0.02 1K 10K 100K FREQUENCY (Hz) 20 101 1M 1D-40 LOAD TRANISENT RESPONSE 200 150 100 50 0 -50 -100 CL = 1F VOUT = 5V 100mA 100A 0 1 2 3 TIME (ms) 4 5 1D-43 800 1D-39 RIPPLE REJECTION CL = 1F VIN = 6V 80 VOUT = 5V 70 IL = 1mA 60 50 40 20 101 106 1D-41 7 60 40 20 0 -20 6 -60 CL = 10F VOUT = 5V 100mA 100A 4 8 12 TIME (ms) 16 20 10 2 103 104 105 FREQUENCY (Hz) 106 1D-42 LP2951 ENABLE TRANSIENT CL = 1F 5 4 IL = 10mA 3 2 -40 0 600 IL = 10mA 103 104 105 FREQUENCY (Hz) LOAD TRANSIENT RESPONSE 80 OUTPUT VOLTAGE CHANGE (mV) 250 10 2 OUTPUT VOLTAGE (V) 100 200 400 TIME (s) 30 VOUT = 5V 0.01 10 6V 90 80 60 VOUT = 5V 8V 0 SHUTDOWN PIN VOLTAGE (V) 1 1D-37 IO = 100A CL = 1A IL = 1mA 4V 0.0 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 OUTPUT LOW VOLTAGE (V) 1D-38 5 OUTPUT IMPEDANCE 10 2 4 2 3 INPUT VOLTAGE (V) RIPPLE REJECTION (dB) 1 0 -50mV 1.0 1D-36 50mV INPUT VOLTAGE 4 1.0 LINE TRANSIENT RESPONSE 100mV TA = 125C 2.0 SINK CURRENT (mA) 6 -250 0 0.5 -2.0 -1.5 -1.0 -0.5 FEEDBACK VOLTAGE (V) OUTPUT VOLTAGE CHANGE LP2951 ERROR COMPARATOR OUTPUT RIPPLE REJECTION (dB) COMPARATOR OUTPUT (V) PIN 7 DRIVEN BY EXTERNAL SOURCE 0 (REGULATROR RUN OPEN LOOP) TA = -55C 1.6 -75 -50 -25 0 25 50 75 100 125 150 TEMPERATURE (C) 1D-34 0 OUTPUT IMPEDANCE (OHMS) -10 -20 -2 OUTPUT VOLTAGE CHANGE (mV) 0 1.7 LP2951 FEEDBACK PIN CURRENT 50 10 BIAS CURRENT (nA) 2.0 8 LOAD CURRENT LP2951 FEEDBACK BIAS CURRENT 20 FEEDBACK CURRENT (A) 2.2 LOAD CURRENT MINIMUM OPERATING VOLTAGE (V) TYPICAL PERFORMANCE CHARACTERISTICS (continued) 1 VIN = 8V CL = 10F VOUT = 5V 0 2 0 -2 -100 0 100 200 300 400 500 600 700 TIME (s) 1D-45 1D-44 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 LP2950 / LP2951 CORPORATION TYPICAL APPLICATIONS +VIN 4.75V OUTPUT VOLTAGE 8 100K 5 ERROR OUTPUT ERROR* +VIN ERROR VOUT 1.2 TO 30V 1 LP2951 + 3 SHUTDOWN INPUT .01F FB GND 5.0V INPUT VOLTAGE 3.3F R1 SD 4 7 1.23V 1.3V R2 VREF *SEE APPLICATION INFO. 1F-44 1F-45 FIGURE 1. ERROR OUTPUT TIMING FIGURE 2. ADJUSTABLE REGULATOR +VIN +VIN 8 470K 5 470K 8 +VIN ERROR VOUT VOUT 1 5 ERROR OUTPUT +VIN ERROR LP2951 VOUT 1 *VOUT = VIN LP2951 + 3 R1 SD GND 4 1F FB SHUTDOWN INPUT 3 SD GND 7 4 FB 7 R2 *MINIMUM INPUT - OUTPUT VOLTAGE RANGES FROM 4mV TO 400mV. DEPENDING ON LOAD CURRENT. CURRENT LIMIT IS TYPICALLY 160mA. LATCH OFF WHEN ERROR FLAG OCCURS 1F-46 WIDE INPUT VOLTAGE RANGE CURRENT LIMITER 1F-47 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 LP2950 / LP2951 CORPORATION TYPICAL APPLICATIONS (continued) + 6V SEALED LEADACID BATTERY SOURCE 120K 1.5K 8 +VIN IN457 FB VOUT CLM385 1 MAIN V- LP2951 400K MEMORY V+ SENSE FOR 5.5V 3 100K + 1F SD NI-CAD BACKUP BATTERY 4 LOW BATTERY DISCONNECT 1G-24 8 39k 2 SENSE +VIN 5 ERROR VOUT RESET 1 + 3 C4 1F 100k 7 SD GND TAP 4 6 39k 1% +VOUT = 5V + LP2951 - 20K GND - 100k C1 + 6V LEADACID BATTERY <5.8V** 1% 1k - 100k C2 + <6.0V** 1% 1k - 100k C3 + <6.2V** 10k R3 1% 20k *OPTIONAL LATCH OFF WHEN DROPOUT OCCURS. ADJUST R3 FOR C2 SWITCHING WHEN VIN IS 6.0V. **OUTPUTS GO LOW WHEN VIN DROPS BELOW DESIGNATED THRESHHOLDS. REGULATOR WITH STATE-OF-CHARGE INDICATOR 1G-25 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 LP2950 / LP2951 CORPORATION TYPICAL APPLICATIONS (continued) +VIN 8 3 AUX SHUTDOWN INPUT OFF 10K +VIN SD ERROR ON 5 5 DEGREE SHUTDOWN FLAG LP2951 VOUT GND FB 4 7 1 EXTERNAL CIRCUIT PROTECTED FROM OVER TEMPERATURE (V+ GOES OFF WHEN TEMP > 125) + TEMP SENSOR AS35 OR RELAY 8.2K - SYSTEM OVER TEMPERATURE PROTECTION CIRCUIT 1F-48 +5v 4 4.7mA 20mA UNREGULATED INPUT OUTPUT 8 +VIN VOUT 1 5 VOUT IN 1 IN4001 LP2951 330K 2N5432 27K LP2951 0.1F FB 7 3 2 GND VTAP SENSE FB 4 IN457 7 360K GND 4 2 5V OUTPUT + 4.7F LOAD 50mA TO 300mA MIN VOLTAGE = 4V OPEN CIRCUIT DETECTOR FOR 4mA TO 20mA CURRENT LOOP 1F-49 300mA REGULATOR WITH 0.75 DROPOUT 1F-50 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025 LP2950 / LP2951 CORPORATION SCHEMATIC DIAGRAM IN FEEDBACK R18 20k Q15A Q15B 24 Q24 3 Q25 Q26 3 OUT Q9 Q3 Q6 Q7 Q4 R11 18 k SENSE Q8 Q5 Q16 1 Q20 R1 20k Q40 R5 180 k Q21 Q23 C2 40pF R12 110 k Q12 R13 100 k R14 350 k R16 30k Q11 Q29 4 Q18 3 R15 100k R9 27.8k R6 140 k Q13 Q22 R10 150 k R8 31.4k Q41 R30 30k 5V TAP R28 60k 2 Q2 10 R2 50k Q17 1 2 Q1 Q42 R17 12k Q14 R11 20.6 k C1 20pF R27 182k R17 10 Q19 Q28 R3 50k R4 13k 6 R21 8 Q30 Q31 Q37 R22 150k Q36 R23 60k SHDN R24 50k ERROR Q34 Q38 4 R26 60k 2 5 R25 2.8 k -- -- -- DENOTES CONNECTION ON LP2950 ONLY GND Q39 1G-01 CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025