html> Products: CCFL Overview

Application Note # 4

Taiyo Yuden LS Series Inverter On/Off ControlThe following applies to the Taiyo Yuden LS220, LS320, LS380, LS390, LS460, and LS520 inverters, which have brightness control and remote on/off functions:

The on/off of the inverters can be controlled using the remote on'off pin on the input side of the inverter. The circuit for the remote on/off circuitry consists of an active low TTL switch. When the circuit is open, the IC Vcc is cut off. When the circuit is closed, IC Vcc is activated. You would need to place either a mechanical switch or a TTL/CMOS gate between the remote on/off pin and ground and create a condition where the circuit is closed to activate the inverter. Either one of the following will be required for the inverter to operate:
  1. Tie on/off pin to ground.
  2. Add mechanical switch between on/off pin and ground, close switch.
  3. Add TTL/CMOS switch between on/off and ground. Circuit must be closed for unit to operate (as shown below).


 

One recommended use of logic switch for remote on/off is the following. Electrical specification for on/off terminal is Low 0 to 0.4V, -0.4 mA or higher when switch is closed.