SGS-Thomson L4947 free download

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L4947 L4947R 5V-0.5A VERY LOW DROP REGULATOR WITH RESET PRECISE OUTPUT VOLTAGE (5V ± 4%) OVER FULL TEMPERATURE RANGE (­ 40 / 125 °C) VERY LOW VOLTAGE DROP (0.75Vmax) OVER FULL T RANGE OUTPUT CURRENT UP TO 500mA RESET FUNCTION POWER-ON RESET DELAY PULSE DEFINED BY THE EXTERNAL CAPACITOR + 80V LOAD DUMP PROTECTION ­ 80V LOAD DUMP PROTECTION REVERSE VOLTAGE PROTECTION SHORT CIRCUIT PROTECTION AND THERMAL SHUT-DOWN (with hysteresis) LOW START UP CURRENT DESCRIPTION The L4947/L4947R is a monolithic integrated circuit in Pentawatt package specially designed to provide a stabilized supply voltage for automotive and industrial electronic systems. Thanks to its very low voltage drop, in automotive applications the L4947/L4947R can work correctly even during the cranking phase, when the battery voltage BLOCK DIAGRAM Pentawatt ORDERING NUMBER: L4947 L4947R could fall as low as 6V. Furthermore, it incorporates a complete range of protection circuits against the dangerous overvoltages always present on the battery rail of the car. The reset function makes the device particularly suited to supply microprocessor based systems : a signal is available (after an externally programmable delay) to reset the microprocessor at power-on phase ; at power-off, this signal becomes low inhibiting the microprocessor. This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice. December 1991 1/6 L4947 - L4947R ABSOLUTE MAXIMUM RATINGS Symbol Vi Parameter DC Input Voltage DC Reverse Input Voltage Transient Input Overvoltages : Load Dump : 5ms trise 10ms f Fall Time Constant = 100ms RSOURCE 0.5 Field Decay : 5ms tfall 10ms, RSOURCE 10 r Rise Time Constant = 33ms Low Energy Spike : trise = 1µs, tfall = 500µs, R SOURCE 10 fr Repetition Frequency = 5Hz Reset Output Voltage Junction and Storage Temperature Range Value 35 ­ 18 80 Unit V V V ­ 80 ± 100 V V VR TJ, Tstg 35 ­ 55 to 150 V °C Note: The circuit is ESD protected according to MIL-STD-883C. PIN CONNECTION (Top view) THERMAL DATA Symbol Rth j-case Parameter Thermal Resistance Junction-case Max Value 3.5 Unit °C/W TEST CIRCUIT (*) Min. 20µF, ESR < 10 over full temperature range R P (pull up resistor) and RL (load) are both equal to 1K. 2/6 L4947 - L4947R ELECTRICAL CHARACTERISTICS (refer to the test circuit, Vi = 14. 4V, Co = 47µF, ESR < 10, Rp = 1K, RL = 1K, ­40°C TJ 125°C, unless otherwise specified) Symbol Vo Parameter Output Voltage Test Conditions Io = 0mA to 500mA Over Full T Range TJ = 25°C Io = 0mA to (*) 500mA Vi = 6V to 26V ; Io = 5mA Io = 5mA to 500mA Io = 500mA, TJ = 25°C Over Full T Range Io = 0mA, TJ = 25°C Io = 0mA Over Full T Io = 500mA Over Full T Min. 4.80 4.90 6 Typ. 5.00 5.00 2 15 0.40 5 6.5 110 ­ 0.5 50 60 Max. 5.20 5.10 26 10 60 0.55 0.75 10 13 180 Unit V V V mV mV V V mA mA mA mV/°C dB Vi Vo Vo Vi ­V o Iq Operating Input Voltage Line Regulation Load Regulation Dropout Voltage Quiescent Current Vo T S