This document describes the features and characteristics of the AD8240 LED driver/monitor from Analog Devices, including PWM input for LED brightness control, open LED detection, latch-off overcurrent protection, and constant voltage regulated output.
The AD8240 is an LED driver/monitor that supplies a constant 12 V to drive LED lamps when the supply voltage is between 12.5 V and 27 V. A CMOS‑compatible digital input allows PWM control of brightness, and an internal high‑side current‑sense amplifier enables open‑LED detection and over‑current protection.
The device operates from a 9 V to 27 V supply, draws only a few hundred picoamps of current, and is packaged in an 8‑lead MSOP. It is intended for automotive lighting applications where partial‑LED failure monitoring and low‑cost wiring are required.
| Supply Voltage Range | 9 V to 27 V |
|---|---|
| Regulated Voltage Range | 12.5 V to 27 V |
| Operating Current | 300 pA |
| Shutdown Current | 10 pA |
| Operating Temperature Range | -40°C to +125°C |
| Package | 8‑lead MSOP |
| PWM Frequency Range | up to 500 Hz |
The device operates from 9 V to 27 V.
When the sense amplifier output exceeds 5 V, an internal comparator trips and latches off the output voltage; the latch resets on the next PWM cycle.
The driver is designed for PWM frequencies up to 500 Hz.
It is supplied in an 8‑lead MSOP package.