New Industry Products

Taiwan Semiconductor’s CMOS LED IC is Drop-in Replacement for Legacy Bipolar Drivers

August 20, 2020 by Hailey Stewart

This article highlights Taiwan Semiconductor's TSCR4 family of linear CMOS LED driver ICs that provide a much improved performance drop-in replacement for legacy bipolar drivers.

Linear constant-current CMOS driver IC is a direct socket replacement for bipolar components; delivers improved performance at a comparable cost.

Taiwan Semiconductor, a global supplier of discrete power electronics devices, LED drivers, analog ICs, and ESD protection devices, announces the availability of the TSCR4 family of linear CMOS LED driver ICs, providing a much-improved performance drop-in replacement for legacy bipolar drivers. These constant current drivers provide stable LED current over a wide range of conditions including source voltage variations, changes in load, or temperature variations. Compared to legacy bipolar LED drivers, the TSCR4 family offers higher current setpoint accuracy and stability, lower quiescent current, tighter output compliance voltage, and improved temperature coefficient. These ICs enable upgrades of existing designs for higher performance with no re-design effort required.


Image courtesy of Taiwan Semiconductor



The TSCR4 family of linear constant current LED drivers offers designers a number of benefits and improvements over competing bipolar devices:

  • Higher accuracy of output current. Improves manufacturing yields in mass production.
  • Lower quiescent current (e.g., 300ma vs 1A @ 24 VDC). Lowers power dissipation and reduces battery standby and operating power consumption.
  • More precise output voltage drop. CMOS control of voltage drop enables operation closer to the rail.
  • Higher stability of output current. Delivers consistent brightness control and extends LED life.
  • Better temperature coefficient (-0.07%/ C). Controls output current with temperature increases to eliminate risk of thermal runaway.
  • AEC-Q100 parts available. Ideal for many basic automotive lighting applications.
  • PWM dimming. Up to 10KHz digital input for 0 to 100% dimming (TSCR421CX6/H).
  • Supply voltage up to 40V. Supports large LED arrays.
  • Easy parallel driver structure.

“The TSCR4 family of LED driver ICs is the perfect part to upgrade a legacy design,” reported Sam Wang, Vice President, TSC Products. “The features and performance of these devices at an affordable price point make them an excellent candidate for new designs, as well.”

Applications include automobile, truck and bus interior and exterior lighting, architectural lighting, signage, advertising and decorative lighting, lighting in refrigerators, freezer cases, kiosks and vending machines, emergency lighting (EXIT signs, stairstep and emergency exit pathway lighting systems).

Design resources include a comprehensive datasheet and interactive designer worksheet.

Price (OEM Quantities): AEC-Q100 version – from $0.46 / General Purpose - from $0.31

Lead Time: Samples in-stock (Digi-Key and Mouser)


About Taiwan Semiconductor

Taiwan Semiconductor was established in 1979 and remains under the direction of its founder and CEO, Arthur Wang. The company has grown from its beginnings as a local manufacturer, to a global enterprise with 2,000 employees.