SC4431 SC431L SC4431CSK-X SC4431- SC4431-1 SC4431-2 ECN99-746

OBJECTIVE - December 6, 1999 SC4431 TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com DESCRIPTION The SC4431 is a four

OPTO DRIVER OBJECTIVE - December 6, 1999 SC4431 SC4431 TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com DESCRIPTION The SC4431 SC4431 is a four terminal device for regulating an isolated power supply with very low output voltage. It is intended to be used as a replacement for three terminal shunt regulators such as SC431L SC431L where the output voltage is too low for them to function in conjunction with an opto-isolator. It achieves this by having seperate supply and output pins; allowing the output to sink current at voltages as low as 0.2V, while the supply pin still has sufficient voltage for the device to function. In this way, allowing for a 1.6V drop through an opto-isolator diode, regulation down to 1.8V out can be achieved. The SC4431 SC4431 shunt regulator is available with three initial reference voltage accuracies (0.5%, 1.0% and 2.0%) in the space saving 5-lead SOT-23 package. The three voltage tolerances allow the designer the opportunity to select the proper cost/tolerance for their application. FEATURES · 40mA drive capability · Trimmed bandgap design + 0.5% APPLICATIONS · Opto Driver for very low output voltage supplies (down to ~1.5V out) ORDERING INFORMATION ORDERING INFORMATION (1)(2) Part Number SC4431CSK-X SC4431CSK-X TYPICAL APPLICATION CIRCUIT Package SOT-23-5 Notes: (1) Add suffix `TR' for Tape & Reel. (2) Where "-X" denotes initial reference voltage tolerance. Available options are ±0.5% (-.5), ±1% (-1) and ±2% (-2). 1 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 OPTO DRIVER SC4431 SC4431 OBJECTIVE - December 6, 1999 ABSOLUTE MAXIMUM RATINGS Parameter Symbol Maximum Units Input Supply Voltage VCC -0.5 to +16 V Output Voltage VOUT -0.5 to +16 V Reference Voltage VREF -0.5 to +4 V Continuous Output Current IOUT 40 mA Reference Input Current IREF 5 mA Operating Ambient Temperature Range TA -40 to +85 °C Operating Junction Temperature Range TJ -40 to +150 °C TSTG -65 to +150 °C Thermal Impedance Junction to Ambient JA 256 °C/W Thermal Impedance Junction to Case JC 81 °C/W Power Dissipation at TA = 25°C PD 475 mW Lead Temperature (Soldering) 10 seconds TLEAD 300 °C ESD Rating (Human Body Model) ESD 2 kV Storage Temperature Range ELECTRICAL CHARACTERISTICS Unless specified, TA = 25°C, VCC = 2V, IOUT = 2mA. Values in bold apply over full operating temperature range. Parameter Symbol Test Conditions MIN TYP MAX Units 15 V VCC Input Supply Voltage VCC Input Supply Current ICC VREF = VOUT 110 200 µA ICC(OFF) VREF = 1.187V, VOUT = 6V 20 50 µA Off State Input Supply Current 1.5 100 REF Reference Voltage VREF SC4431- SC4431-.5, VREF = VOUT 1.219 1.224 1.231 1.207 SC4431-1 SC4431-1, VREF = VOUT 1.243 1.212 1.224 1.236 1.200 SC4431-2 SC4431-2, VREF = VOUT in VCC Change in VREF due to change in IOUT dVREF dVCC VCC = 1.5V to 15V dVREF dIOUT IOUT = 0.1mA to 40mA V 1.250 1.200 1.224 1.250 1.187 Change in VREF due to change V V 1.261 4 15 mV 20 8 28 mV 36 2 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 OPTO DRIVER SC4431 SC4431 OBJECTIVE - December 6, 1999 ELECTRICAL CHARACTERISTICS (Cont.) Unless specified, TA = 25°C, VCC = 2V, IOUT = 2mA. Values in bold apply over full operating temperature range. Parameter Symbol Test Conditions IREF 0.1mA IOUT 10mA MIN TYP MAX Units 0.1 0.5 µA REF (Cont.) Reference Input Current 1.0 OUT Saturation Voltage VOUT(SAT) IOUT = 5mA, ICC = 500µA 52 75 mV 100 VREF = 1.261V, IOUT = 40mA 275 300 mV 400 Off State Output Current IOUT(OFF) VREF = 1.187V, VOUT = 6V 0.20 1 µA 10 3 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 OPTO DRIVER SC4431 SC4431 OBJECTIVE - December 6, 1999 BLOCK DIAGRAM PIN CONFIGURATION SOT-23 -5 Lead (Top View) PIN DESCRIPTION Pin Pin Name Pin Function 1 VCC This is the input supply pin for the IC. 2 GND Logic and power ground. 3 NC No connection. 4 REF This is connected to the non-inverting input of the error amplifier. 5 OUT This is the output pin of the device, essentially an open collector. 4 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 OPTO DRIVER SC4431 SC4431 OBJECTIVE - December 6, 1999 OUTLINE DRAWING - SOT-23-5L LAND PATTERN - SOT-23-5L 5 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 OPTO DRIVER SC4431 SC4431 OBJECTIVE - December 6, 1999 TYPICAL CHARACTERISTICS 6 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 OPTO DRIVER SC4431 SC4431 OBJECTIVE - December 6, 1999 APPLICATIONS INFORMATION ECN99-746 ECN99-746 7 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320