L4937NPD DUAL 5V MULTIFUNCTION VOLTAGE REGULATOR . . . . .. . . . . STANDBYOUTPUT VOLTAGEPRECISION 5V ± 2% OUTPUT 2 TRACKED TO THE STANDBY OUTPUT OUTPUT 2 DISABLE FUNCTION FOR STANDBY MODE VERY LOW QUIESCENT CURRENT, LESS THAN 260µA, IN STANDBY MODE OUTPUT CURRENTS : I01 = 50mA, I02 = 500mA VERY LOW DROPOUT (max 0.4V/0.6V) OPERATING TRANSIENT SUPPLY VOLTAGE UP TO 40V POWER-ON RESET CIRCUIT SENSING THE STANDBY OUTPUT VOLTAGE POWER-ON RESET DELAY PULSE DEFINED BY THE EXTERNAL CAPACITOR THERMAL SHUTDOWN AND SHORTCIRCUIT PROTECTIONS PowerSO20 ORDERING NUMBER: L4937NPD DESCRIPTION The L4937NPD is a monolithic integrated dual voltage regulators with two very low dropout outputs andadditionalfunctionssuchas power-onresetand input voltage sense. They are designed for supplying microcomputer controlled systems specially in automotive applications. PIN CONNECTION (top view) GND 1 20 GND N.C. 2 19 N.C. VS 3 18 VO2 VS 4 17 N.C. GND 5 16 VO1 N.C. 6 15 GND CT 7 14 RESET N.C. EN 8 13 N.C. 9 12 N.C. GND 10 11 GND D95AT162A June 2000 1/9 This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice. L4937NPD BLOCK DIAGRAM VS1 VO1 REFERENCE 1.23V REG1 VS2 VO2 EN REG2 1.23V CT 2µ RES 2.0V RESET GND D95AT163 THERMAL DATA Symbol Rthj-case 2/9 Parameter Thermal Resistance Junction-Case Max. Value Unit 1.5 °C/W L4937NPD ABSOLUTE MAXIMUM RATINGS Symbol VS Parameter Value Unit DC Supply Voltage 28 V Transient Supply Voltage (T < 1s) 40 V –55 to 150 °C IEN Enable Input Current (VEN ≤0.3V) ±1 mA Tj, Tstg Junction and Storage Temperature Range VEN Enable Input Voltage VS VRES Reset Output Voltage 20 IRES Reset Output Current PD Power Dissipation V 5 mA 875 mW Note : The circuit is ESD protected according to MIL–STD–883C. APPLICATION CIRCUIT VS1 VO1 CS CO1 REFERENCE 1.23V REG1 VO2 VS2 EN REG2 CT 1.23V RES 2µ RESET CT 2.0V GND D95AT164 CS ≥ 1µF ; C01 ≥ 6µF ; C02 ≥ 10µF, ESR < 10Ω at 10KHz 3/9 L4937NPD ELECTRICAL CHARACTERISTICS (VS = 14V; –40°C ≤ TJ ≤ 125°C unless otherwise specified) Symbol Parameter Test Conditions Min. Max. Unit 25 V 5.10 V +25 mV 0.25 0.4 V V 0.4 V 0.3 0.6 V V Vs = 4.6V, IO1 = 350mA 0.6 V Line Regulation 6V ≤ VS ≤ 25V IO1 = 1mA; IO2 = 5mA 20 mV VOLO1 Load Regulation 1 1mA ≤ IO1 ≤ 50mA 25 mV VOLO2 Load Regulation 2 5mA ≤ IO2 ≤ 500mA 50 mV ILIM1 Current Limit 1 VO1 = 4.5V VO1 = 0V (note 1) 55 25 100 50 200 100 mA mA ILIM2 Current Limit 2 VO2 = 0V 550 1000 1700 mA IQSB Quiescent Current Standby Mode IO1 = 0.3mA; T J < 100°C (output 2 disabled) VEN ≥ 2.4V VS = 14V VS = 3.5V 210 340 290 850 µA µA 30 mA 1.5 V VS Operating Supply Voltage V O1 Standby Output Voltage 6V ≤ VS ≤ 25V 1mA ≤ IO1 ≤ 50mA 4.90 Output Voltage 2 Tracking Error 6V ≤ VS ≤ 25V 5mA ≤ IO2 ≤ 500mA Enable = LOW –25 VDP1 Dropout Voltage 1 IO1 = 10mA IO1 = 50mA V IO1 Input to Output Voltage Difference in Undervoltage Condition Vs = 4V, IO1 = 35mA VDP2 Dropout Voltage 2 IO1 = 100mA IO1 = 500mA V IO2 Input to Output Voltage Difference in Undervoltage Condition VOL 1.2 VO2 - VO1 IQ Quiescent Current Typ. 5.00 0.1 0.2 0.2 0.3 IO1 = 50mA IO1 = 500mA ENABLE VENL Enable Input LOW Voltage (output 2 active) –0.3 VENH Enable Input HIGH Voltage 2.4 7 V Enable Hysteresis 30 75 200 mV –10 –1 –1.5 0 –0.5 +1 µA µA VENhyst IEN 4/9 Enable Input Current 0V < VEN < 1.2V 2.5V < VEN < 7V L4937NPD ELECTRICAL CHARACTERISTICS (continued) RESET Symbol Parameter VRt Reset Low Threshold Voltage VRth Reset Threshold Hysteresis Test Conditions Min. Typ. Max. Unit Vo1 -0.4 4.7 Vo1 -0.1 V 50 100 200 mV tRD Reset Pulse Delay CT = 100nF; tR > 100µs 55 100 180 ms tRR Reset Reaction Time CT = 100nF 1 10 50 µs VRL Reset Output LOW Voltage RRES = 10KΩ to V01 VS = 1.5V 0.4 V ILRES Reset Output HIGH Leakage VRES = 5V 1 µA VCTh Delay Comparator Threshold 2.0 V VCTh, hyst Delay Comparator Threshold Hysteresis 100 mV Note : 1: Foldback characteristic FUNCTIONAL DESCRIPTION The L4937NDis based on the SGS-THOMSON Microelectronics modular voltage regulator approach. Several out-standing features and auxiliary functions are provided to meet the requirements of supplying the microprocessor systems used in automotive applications. Furthermore the device is suitable also in other applications requiring two stabilized voltages. The modular approach allows other features and functions to be realized easily when required. STANDBY REGULATOR The standby regulator uses an Isolated Collector Vertical PNP transistor as the regulating element. This structure allows a very low dropout voltage at currents up to 50mA. The dropout operation of the standby regulator is maintained down to 2V input supply voltage. The output voltage is regulated up to the transientinput supplyvoltageof 40V.This feature avoids functional interruptions which could be generated by overvoltage pulses. The typical curve of the standby output voltage as a functionof the input supply voltage is shown in fig. 1. The current consumption of the device (quiescent current) is less than 260µA when output 2 is disabled (standby mode). The dropout voltage is controlled to reduce the quiescent current peak in the undervoltage region and to improve the transient response in this region. The quiescentcurrent isshown in fig. 2 as a function of the supply input voltage 2. OUTPUT 2 VOLTAGE The output 2 regulator uses the same output structure as the standbyregulator, but rated for anoutput current of 500mA. The output 2 regulatorworks in tracking mode with the standby output voltage as a reference voltage when the output 2. The output 2 regulator can be switched off via the Enable input. Figure 1 : Output Voltage vs. Input Voltage. 5/9 L4937NPD Figure 2 : QuiescentCurrent vs. Supply Voltage. 400µ 200µ Figure 3 : Programmable Output 2 Voltage with External Resistors. RESET CIRCUIT Theblockcircuit diagramof thereset circuit is shown in fig.4. The resetcircuit supervisesthe standbyoutput voltage. The reset threshold of 4.7V is defined by the internal reference voltage and the standby output divider. The reset pulse delay time tRD, is defined by the charge time of an external capacitor CT : CT x 2V tRD = 6/9 2µA The reactiontime of the reset circuit dependson the discharge time limitation of the reset capacitor CT and is proportional to the value of CT. The reaction time of the reset circuit increases the noise immunity. In fact,if the standbyoutputvoltage drops below the reset threshold for a time shorter than the reaction time tRR, no reset output variation occurs. The nominal reset delay is generated for standby output voltage drops longer than the time necessary for the complete discharging of the capacitor CT. This time is typically equal to 50µs if CT = 100nF.The typical reset output waveforms are shown in fig. 5. L4937NPD Figure 4 :Block Diagram of the Reset Circuit. Figure 5 : Typical Reset Output Waveforms. VOUT1 VINPUT VOUT1 VRT +0.2V VRT 1.5V tR RESET tRD tRD tRR D95AT216 7/9 L4937NPD DIM. A a1 a2 a3 b c D (1) D1 E e e3 E1 (1) E2 E3 G H h L N S T MIN. mm TYP. 0.1 0 0.4 0.23 15.8 9.4 13.9 MAX. 3.6 0.3 3.3 0.1 0.53 0.32 16 9.8 14.5 MIN. 0.004 0.000 0.016 0.009 0.622 0.370 0.547 1.27 11.43 10.9 inch TYP. 0.050 0.450 11.1 0.429 2.9 6.2 0.228 0.1 0.000 15.9 0.610 1.1 1.1 0.031 10° (max.) 8° (max.) 5.8 0 15.5 0.8 OUTLINE AND MECHANICAL DATA MAX. 0.142 0.012 0.130 0.004 0.021 0.013 0.630 0.386 0.570 10 0.437 0.114 0.244 0.004 0.626 0.043 0.043 JEDEC MO-166 0.394 PowerSO20 (1) ”D and F” do not include mold flash or protrusions. - Mold flash or protrusions shall not exceed 0.15 mm (0.006”). - Critical dimensions: ”E”, ”G” and ”a3” N R N a2 b A e DETAIL A c a1 DETAIL B E e3 H DETAIL A lead D slug a3 DETAIL B 20 11 0.35 Gage Plane -C- S SEATING PLANE L G E2 E1 BOTTOM VIEW T E3 1 h x 45 8/9 10 PSO20MEC C (COPLANARITY) D1 L4937NPD Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. 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