Preliminary

PT6910

1.2A LED Driver with Integrated Switch

DESCRIPTION

The PT6910 is a continuous mode inductive step-down

converter, designed for driving single or multiple series

white LEDs efficiently from a voltage source higher than

the output LED voltage. The IC operates from an input

supply between 6V and 36V and provides an externally

adjustable output current of up to 1.2Amp.

The PT6910 includes the internal switch and a high-side

output current sensing circuit, which uses an external

resister to set the average output current. Also the output

current can be adjusted below the set value by using the

external ADJ pin.

The ADJ pin will accept either a DC voltage or a PWM

waveform. Depending upon the control PWM frequency,

the IC will provide either a continuous or a gated output

current with the internal PWM filter circuit.

The PT6910 provides a soft-start feature. And the

soft-start time can be increased by using an external

capacitor from the ADJ pin to ground if you need a longer

soft-start time. Anyway if you apply a voltage of 0.2V or

lower the output switch will be off and the IC go into a low

current standby state.

FEATURES

• High Efficiency (up to 95%)

• Soft-Start (Adjustable)

• Maximum 1.2A Output Current

• Low/High Frequency PWM Dimming with Internal

PWM Filter

• Wide Input Voltage: 6V ~ 36V

• Internal Open-Circuit LED Protection

• Typical 5% Output Current Accuracy

• SOT-89-5L

APPLICATIONS

• DC/DC LED Driver

• Low Voltage Industrial LED Lighting

• Low Voltage Halogen Replacement LEDs

• Decorative LED Lighting

• LED Table Lighting

BLOCK DIAGRAM