TSCR420 TSCR421 TSCR420CX6 / TSCR421CX6 Taiwan Semiconductor Linear Constant Current Regulated LED Driver DESCRIPTION FEATURES The TSCR420 & TSCR421 are Low-Side Constant LED drive current preset to 10mA Current Regulator (CCR) for linear LED driving. The Continuous output current up to 300mA with an device regulates with a preset 10mA nominal that can external resistor be adjusted with an external resistor up to 300mA. It is Very low enable current designed for driving LEDs in strings and will reduce Easy paralleling of drivers to increase current current at increasing temperatures to self-protect. Supply voltage up to 40V Operating as a series linear CCR for LED string Digital PWM input up to 10kHz (TSCR421) current control, it can be used in multiple applications, Good temperature coefficient vs. output current as long as the maximum supply voltage to the device Compliant to RoHS Directive 2011/65/EU and in is <40V. accordance to WEEE 2002/96/EC. With the low-side control, the TSCR421 has an Enable Halogen-Free according to IEC 61249-2-21 (EN) pin which can be pulse-width modulated (PWM) APPLICATION up to 10kHz by a microcontroller for LED dimming. Automotive Interior Lighting The output current at higher temperatures is the result Architectural LED lighting of the negative temperature coefficient of -0.07%/C of Signage, Advertising, Decorative Lighting the LED driver. Retail Lighting in Fridges, Freezer Cases and Vending Machines Emergency lighting (e.g. steps lighting, exit way signs etc.) SOT-26 Pin Definition: 1. EN 6. R EXT 2. OUT 5. OUT 3. OUT 4. GND Notes: MSL 1 (Moisture Sensitivity Level) per J-STD-020 TYPICAL APPLICATION CIRCUIT Vs Supply LED String EN OUT Regulator Vref Vref REXT R (Optional) INT GND 1 Version: B1708 TSCR420CX6 / TSCR421CX6 Taiwan Semiconductor (Note 1) ABSOLUTE MAXIMUM RATINGS (T = 25C unless otherwise specified) A PARAMETER SYMBOL LIMIT UNIT 40 TSCR420 Enable Voltage V V EN 4.5 TSCR421 Output Current I 300 mA OUT V 40 V Output Voltage OUT Reverse voltage between all terminals V 0.5 V R (Note) P 1 W Total power dissipation T =25 C TOT A T -55 to +150 C Junction Temperature Range J T -65 to +150 C Storage Temperature Range STG ESD Rating (Human Body Mode) HBM 2 kV ESD Rating (Machine Mode) MM 200 V Note: Stresses above the max. values listed here may cause permanent damage to the device. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Maximum ratings are absolute ratings exceeding only one of these values may cause irreversible damage to the integrated circuit. THERMAL PERFORMANCE PARAMETER SYMBOL LIMIT UNIT Thermal Resistance - Junction to Lead R 50 C/W JL ELECTRICAL SPECIFICATIONS (T = 25C unless otherwise noted) A PARAMETER CONDITIONS SYMBOL MIN TYP MAX UNIT Break Down Voltage V 40 -- -- V BR V =24V TSCR420 EN -- 450 -- A Enable Current I EN V =3.3V TSCR421 -- 36 -- A EN I =10mA Internal Resistor RINT R 85 95 105 INT V =1.4V, V =24V TSCR420 9 10 11 OUT EN Output Current V =1.4V, V =3.3V TSCR421 OUT EN 9 10 11 I mA OUT V >2.0V, V =24V TSCR420 -- 150 -- Output Current at OUT EN R =5.1 V >2.0V, V =3.3V EXT TSCR421 OUT EN -- 150 -- I =10mA Voltage Drop (V ) V 0.85 0.95 1.05 V OUT REXT DROP Minimum Output Voltage I >18mA OUT V -- 1.4 -- V OUT(MIN) V >2.0V, V =24V TSCR420 -- -0.07 -- OUT EN Output Current I /I %/C OUT OUT vs. Temperature V >2.0V, V =3.3V TSCR421 OUT EN -- -0.07 -- V >2.0V, V =24V TSCR420 -- 0.33 -- OUT EN Output Current I /I %/V OUT OUT vs. Supply Voltage V >2.0V, V =3.3V TSCR421 OUT EN -- 0.33 -- 2 Version: B1708