The HT7939A-1 is an LED driver integrated circuit (IC) from Holtek. It is a 6-pin SOT23 type IC with RoHS compliance. The device is designed specifically to drive LEDs, providing low current ripple, balanced current, and lower supply voltage. It has a constant LED current of 19.5mA, adjustable from 15mA to 32mA. The device has an operating temperature of -20 to 70°C and a wide input voltage range of 2.5V to 5.5V. It features strong EMI immunity capability, LED short circuit protection, and LED open circuit protection.