The NCV7681 consists of eight linear programmable constant

current sources. The part is designed for use in the regulation and

control of LED based Rear Combination Lamps and blinking

functions for automotive applications. System design with the

NCV7681 allows for two programmed levels for stop (100 Duty

Cycle) and tail illumination (programmable Duty Cycle), or an

optional external PWM control can be implemented.

LED brightness levels are easily programmed (stop is programmed

to the absolute current value, tail is programmed to the duty cycle)

with two external resistors. The use of an optional external ballast FET

allows for power distribution on designs requiring high currents. Set

back power limit reduces the drive current during overvoltage

conditions. This is most useful for low power applications when no

external FET is used.

The device is available in a SOIC−16 WB package with exposed pad.

Features

• Constant Current Outputs for LED String Drive

• LED Drive Current up to 100 mA per Channel

• Open LED String Diagnostic with Open−Drain Output in All Modes

• Slew Rate Control Eliminates EMI Concerns

• Low Dropout Operation for Pre−Regulator Applications

• External Modulation Capable

• On−chip 800 Hz Tail PWM Dimming

• Single Resistor for Stop Current Set Point

• Single Resistor for Tail Dimming Set Point

• Overvoltage Set Back Power Limitation

• AEC−Q100 Qualified and PPAP Capable

• 16 Lead SOICW Exposed Pad

• Improved EMC Performance

• Latch−Off Function on Open String (NCV7681L)

♦ Restart Option of Unaffected Strings

• Over Temperature Fault Reporting

• These are Pb−Free Devices

Applications

• Rear Combination Lamps (RCL)

• Daytime Running Lights (DRL)

• Fog Lights

• Center High Mounted Stop Lamps (CHMSL) Arrays

• Turn Signal and Other Externally Modulated Applications

• Signature Lamp