L4925PD

L4925 STMICROELECTRONICS | Alldatasheet

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VERY LOW DROP VOLTAGE REGULATOR OPERATING DC SUPPLY VOLTAGE RANGE 6V TO 28V TRANSIENT SUPPLY VOLTAGE UP TO 40V EXTREMELY LOW QUIESCENT CURRENT HIGH PRECISION OUTPUT VOLTAGE OUTPUT CURRENT CAPABILITY UP TO 500mA VERY LOW DROPOUT VOLTAGE LESS THAN 0.6V RESET CIRCUIT SENSING THE OUTPUT VOLTAGE PROGRAMMABLE RESET PULSE DELAY WITH EXTERNAL CAPACITOR THERMAL SHUTDOWN AND SHORT CIR- CUIT PROTECTIONS

DESCRIPTION

The L4925 is a monolithic integrated 5V voltage regulator with a very low dropout output and addi- tional functions such as power-on reset and pro- grammable reset delay time. It is designed for supplying microcomputer controlled systems es- pecially in automotiveapplications. This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice. June 2000 PREREGULATOR VREF 1.23V Vz Vz VS GND RESETREG L4925N VO CT RES D95AT151 C S BLOCK DIAGRAM ORDERING NUMBERS: L4925 (Pentawatt) L4925PD (PowerSO20) Pentawatt PowerSO20

Symbol Parameter Value Unit V SDC DC Operating Supply Voltage 28 V VSTR Transient Supply Voltage (t < 1s) 40 V IO Output Current internally limited VO Output Voltage 20 V VRES Output Voltage 20 V IRES Output Current 5 mA Tstg Storage Temperature -55 to 150 °C Tj Operating Junction Temperature -40 to 150 °C Tj-SD Thermal Shutdown-Junction Temperature 165 °C NOTE: The circuit is ESD protected according to MIL-STD-883C. According to ISO/DIS 7637 the transients must be clamped with external circuitry (see Application Circuit). THERMAL DATA Symbol Parameter Pentawatt SO 20 Unit R th j-amb R th j-case Thermal resistance junction to ambient max. Thermal resistance junction to case max. 3.5 77 to 97 °C/W °C/W N.C. N.C. VS VS N.C. RES N.C. N.C. N.C. N.C. N.C. CT VOUT N.C. VOUT N.C. N.C. N.C.1 GND N.C. D95AT152 L4925

ELECTRICAL CHARACTERISTICS (VS =14V Tj=–40 to 125°C unless otherwise specified; Symbol Parameter Test Condition Min. Typ. Max. Unit VO Output Voltage V I = 6 to 28V; IO = 1 to 500mA 4.90 5 5.10 V VO Output Voltage V I = 35V; T <1s; IO = 1 to 500mA 5.50 V VDP Dropout Voltage I O = 100mA IO = 500mA 0.2 0.3 0.3 0.6 V V VIO Input to Output Voltage Difference in Undervoltage Condition VI = 4V; IO = 100mA 0.5 V V OL Line Regulation V I = 6 to 28V; IO = 1 to 1mA 10 mV VOLO Load Regulation I O = 1 to 500mA 50 mV ILIM Current Limit V O = 4.5V; VO = 0; Foldback characteristic 550 1000 250 1500 mA mA IQSE Quiescent Current I O = 0.3mA 190 360 µA IQ Quiescent Current I O = 500mA 20 mA RESET Symbol Parameter Test Condition Min. Typ. Max. Unit V RT Reset Threshold Voltage 4.5 5.2 V VRTH Reset Threshold 50 100 200 mV tRD Reset Pulse Delay C T = 100nF; tR > 100µs 60 100 140 ms tRR Reset Reaction Time C T = 100nF; 5 30 µs V RL Reset Output LOW Voltage R RES = 10KΩ to VO ;VS => 3V 0.4 V IRH Reset Output HIGH Leakage Current VRES =5 V 1 µA VCTth Delay Comparator Threshold 2 V VCTth hy Delay Comparator Threshold Hysteresis 200 mV PREREGULATOR VREF 1.23V Vz Vz VS GND RESETREG L4925N Vo CT RES D95AT153 VBAT C S Co Vout RES APPLICATION CIRCUIT DIAGRAM For stability: CS >1 µF; CO >1 0µF;ESR < 2.5Ω at 10 KHz Recommended for application: CS =C O =1 0µF to 100µF L4925

High supply voltage transients can cause a reset output signal disturbation. For supply voltage greater than 8V the circuit shows a high immunity of the reset output against supply transients of more than 100V/µs. For supply voltage lower than 8V, supply tran- sients of more than 0.4V/µs. can cause a reset signal disturbation. Foldback Characteristics Of Vo FUNCTIONAL DESCRIPTION The L4925 is a monolithic integrated voltage regulator, based on the STM modular voltage regulator approach. Several outstanding features and auxiliary functions are implemented to meet the requirements of supplying microprocessor systems in automotive applications. Nevetrheless, it is suitable also in other applica- tions where the present functions are required. The modular approach of this device allows to get easily also other features and functions when re- quired. VOLTAGE REGULATOR The voltage regulator uses an Isolated Collector Vertical PNP transistor as a regulating element. With this structure very low dropout voltage at currents up to 500mA is obtained. The dropout operation of the standby regulator is maintained down to 3V input supply voltage. The output voltage is regulated up to the transient in- put supply voltage of 35V. With this feature no functional interruption due to overvoltage pulses is generated. The typical curve showing the standby output voltage as a function of the input supply voltage is shown in fig. 1. The current consumption of the device (quiescent current) is less than 250µA. To reduce the quiescent current peak in the un- dervoltage region and to improve the transient re- sponse in this region, the dropout voltage is con- trolled. The quiescent current as a function of the supply input voltage is shown in fig. 2. Figure 1:Output Voltage vs. Input Voltage Figure 2:Quiescent Current vs. Supply Voltage L4925

DIM. mm inch A 4.8 0.189 C 1.37 0.054 D 2.4 2.8 0.094 0.110 D1 1.2 1.35 0.047 0.053 E 0.35 0.55 0.014 0.022 E1 0.76 1.19 0.030 0.047 F 0.8 1.05 0.031 0.041 F1 1 1.4 0.039 0.055 H2 10.4 0.409 H3 10.05 10.4 0.396 0.409 L4 1.29 0.051 L5 2.6 3 0.102 0.118 L6 15.1 15.8 0.594 0.622 L7 6 6.6 0.236 0.260 L9 0.2 0.008 V4 40 °(typ.) L A C D1 L2 E MD Dia. F GG 1 F E R R R RESIN BETWEEN LEADS VV V1 B VV OUTLINE AND MECHANICAL DATA L4925

e a2 A E PSO20MEC DETAIL A T D 1120 E1E2 hx 45 DETAIL Alead sluga3 S Gage Plane 0.35 L DETAIL B R DETAIL B (COPLANARITY) GC -C - SEATING PLANE b c NN H BOTTOM VIEW DIM. mm inch A 3.6 0.142 a1 0.1 0.3 0.004 0.012 a2 3.3 0.130 a3 0 0.1 0.000 0.004 b 0.4 0.53 0.016 0.021 c 0.23 0.32 0.009 0.013 D (1) 15.8 16 0.622 0.630 D1 9.4 9.8 0.370 0.386 E 13.9 14.5 0.547 0.570 e 1.27 0.050 e3 11.43 0.450 E1 (1) 10.9 11.1 0.429 0.437 E2 2.9 0.114 E3 5.8 6.2 0.228 0.244 G 0 0.1 0.000 0.004 H 15.5 15.9 0.610 0.626 h 1.1 0.043 L 0.8 1.1 0.031 0.043 N1 0 °(max.) S T 10 0.394 (1) ”D and F” do not include mold flash or protrusions . - Mold flash or protrusio ns shall not exce ed 0.15 mm (0.006 ”). - Critical dimens ions: ”E”, ”G” and ”a3” OUTLINE AND MECHANICAL DATA 8°(max.) L4925

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 res ult 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 withoutnotice. This publicationsupersedes and replaces all information previously supplied. STMicroelectronics products are notauthorizedfor use as critical components in life support devices or systems without express writtenapproval ofSTMicroelec tronics . The ST logois a registered trademark of STMicroelec tronics  2000 STMicroelectronics – Printed in Italy – All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - China - Finland - France - Germany - Hong Kong - India - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - U.S.A. http://www.st.com L4925