Key facts
- Brand
- Analog Devices
- Model
- AD8240
- Documents
- 2
- Languages
- EN
- Last added
- 2012-03-28
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Analog Devices AD8240 LED Driver/Monitor Datasheet
The AD8240 is an LED driver and monitor that supplies a constant 12 V to drive LED lamps while offering PWM‑controlled brightness, open‑LED detection, and latch‑off over‑current protection. It operates from a 9 V to 27 V supply and uses an external transistor for low‑power operation.
The device includes a high‑side current‑sense amplifier (gain 24) for monitoring LED current, a comparator that latches off the output when the sense voltage exceeds 5 V, and a linear regulator block that provides a stable output voltage. Typical automotive applications include brake, turn‑signal and running lamps where partial‑LED failure monitoring is required.
Analog Devices AD8240 specifications
| 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 |
| PWM Frequency Range | up to 500 Hz |
| Package | 8‑lead MSOP |
| Vsense Gain | 24 |
All Analog Devices AD8240 documents by type
Ratings, dimensions and ordering codes, for selection and design work.
Questions answered in these manuals
What is the PWM input used for?
The PWM input controls LED brightness and can also serve as a simple on/off control.
How does the AD8240 protect against overcurrent?
A comparator monitors the high‑side current‑sense amplifier; when its output exceeds 5 V the comparator trips and latches off the driver output.
What is the supply voltage range for the AD8240?
The device operates from 9 V to 27 V.
How does the AD8240 protect against over‑current conditions?
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.