Document
CAT4026
6-Channel LED Controller
with Fault Diagnostics for
Large Panel LED
Backlighting
Description
The CAT4026 is a high performance, large panel LED controller designed to control six constant current high voltage LED strings. Added control circuitry monitors the lowest cathode voltage and generates a feedback control signal to an external Switch Mode Power Supply (SMPS) to provide a low cost and efficient solution for large panel high voltage LED backlighting.
Each LED channel current is accurately matched and controlled by sensing an external resistor in series with a low cost bipolar power transistor. This allows current and heat dissipation concerns to be mitigated from the CAT4026 device package.
For added system reliability, both Open−Cathode−Anode (OCA) and Shorted−Cathode−Anode (SCA) fault detection circuitry has been included along with independent Fault flag logic outputs for diagnostic purposes.
LED current dimming in all six channels can be precisely controlled .