The TB9961 is an average current mode control LED driver IC operating in a constant off-time mode. Unlike 
TB99,this control IC does not produce a peak-to-average error, and therefore greatly improves accuracy, line and 
load regulation of the LED current without any need for loop compensation or high-side current sensing. The 
output LED current accuracy is ±3%. 
 
The IC is equipped with a current limit comparator for hiccup-mode output short circuit protection. 
 
The TB9961 can be powered from an 8.0 - 450V supply. A PWM dimming input is provided that accepts an 
External control TTL compatible signal. The output current can be programmed by an internal 275mV reference, 
or controlled externally through a 0 - 1.5V dimming input.