IS31LT3117

IS31LT3117 53V, 350MA, 4-CHANNEL CONSTANT CURRENT REGULATOR WITH OTP GENERAL DESCRIPTION The IS31LT3117 is a 4-channel, linear regulated, constant current LED driver which can provide 4 equal currents outputs of up to 350mA per channel to drive high brightness LEDs over an input voltage range of 6V to 53V, while maintaining an output leakage current of less than 1µA. The output current is easily programmed using a single, tiny external resistor. The outputs of the IS31LT3117 can be connected in parallel to allow greater than 350mA output current. The IS31LT3117 also features a PWM input to enable simple dimming control using a digital control signal. The recommended frequency range of the PWM signal is 4kHz ~ 100kHz. The IS31LT3117 provides a unique over temperature protection scheme. A hard shutdown which turns off all LED currents occurs if the die junction temperature exceeds the maximum value of 160°C. However, as the die junction temperature rises up to over 130°C (Typ.), the output current will begin to roll off at a rate of -2.22%/°C (Typ.). If the die temperature continues to rise above the hard shutdown temperature threshold, the LED currents will drop to zero. When temperature returns to 140°C (Typ.) or below, the hard shutdown protection is released and the chip will function again. The IS31LT3117 also has an optional 2.5V reference voltage output which is able to supply up to 10mA (typ.) output current. This voltage may be used to drive the base of the external B...