Toshiba Electronics Europe has announced two constant current LED driver ICs (CC-driver). The TAH8N401K is a 4-channel driver supplied in Toshiba’s US8 package with a footprint of 3.1mm x 2.0mm. The TAH6N201U 2-channel driver is supplied in Toshiba’s UF6 package and has a footprint of 2.0mm x 2.1mm. Both drivers have a profile of less than 0.8mm.

In the simplest configurations only a single external resistor is connected to the reference voltage pin to set the drive current. Additionally, operation of the CC-drivers in linear control mode is possible with an external PWM signal (1 to 100kHz) applied to either the control or reference voltage pin of the device. In this operation mode linear control between shutdown mode and full driving current is possible by adjusting the duty cycle of the PWM signal. Ideal for portable and battery-powered electronic equipment, the TAH8N401K and TAH6N201U drivers operate with power supply voltages of 2.5V and 5.5V. Efficiency is in excess of 90% with a supply voltage of 3.6V. The driver ICs are designed for parallel LED connection and can deliver drive currents up to a maximum of 25mA per channel. Maximum power dissipation is 400mW for the 4-channel driver and 200mW for the 2-channel device.