Analog Devices Inc. ADM6840 Adjustable Hex/Octal Sequencer-Supervisor
Analog Devices Inc. ADM6840 Adjustable Hex/Octal Sequencer-Supervisor with reverse power-down and daisy-chain capability is designed to manage and monitor up to six or eight voltage rails. The Analog Devices ADM6840 power management integrated circuit (PMIC) provides adjustable delays during power-up and continuously supervises each supply’s voltage. Operating from 2.7V to 15V, the device includes an internal regulator (ABP) to power the internal circuitry, simplifying system design.
Sequencing is controlled through ON and OFF inputs: a rising edge on ON starts power-on sequencing, while a falling edge on OFF triggers power-down. Once all voltages reach targets, the DONE output asserts, followed by the Power-OK (POK) signal after a reset timeout, enabling system operation. If any monitored voltage drops below the threshold, POK deasserts and all outputs shut down simultaneously (during power-off, the device can reverse the sequence). Additional features include an open-drain reset output for daisy-chaining multiple devices and a bidirectional active-low FAULT signal for error handling. Availability in compact package options, the ADM6840 operates from -40°C to +125°C.
Features
- Wide 2.7V to 15V operating voltage range
- Monitor up to eight voltages
- Sequence up to eight voltages
- Power off in reverse order or simultaneously
- Unlimited daisy-chain
- Capacitor-adjustable sequence delay
- Factory-trimmable options power-good timeout
- Resistor-programmable power-supply ON threshold (VSEQON_TH)
- Factory-trimmable options power-supply OFF thresholds (VSEQOFF_TH)
- 0.8% accuracy voltage monitoring threshold (VMON_TH)
- Open-drain output
- Power-ok output (POK) for system microcontroller reset
- Done output (DONE) for sequencing done signal
- Bidirectional FAULT input/output
- 25-bump WLP, 24L and 28L TQFN package
- -40°C to +125°C operating temperature range
- RoHS-compliant
Applications
- Telecom equipment
- Test equipment
- Servers and network cards
- Healthcare imaging
- Industrial sensors and motor controls
- FPGA/ASIC power supply sequencing
- Microprocessor and microcontroller sequencing
- Multi-supply sequencing
Specifications
- 2.7V to 15V operating voltage range
- 2.3V to 2.5V undervoltage lockout range
- 100mV typical undervoltage lockout hysteresis
- 1.8V typical regulated supply voltage
- 370µA maximum supply current, 240µA typical
- On/off inputs
- 0.496V to 0.504V input threshold range
- 1%VON/OFF_TH typical input threshold hysteresis
- 30ppm/°C typical threshold tempco
- ±100nA input current range
- Monitored analog inputs (SET_)
- 0.496V to 0.504V threshold range
- ±0.8% threshold accuracy
- 1%VTH typical threshold hysteresis
- 30ppm/°C typical threshold tempco
- ±100nA input current range
- Delay timer (DLY)
- 3.8µA to 4.2µA source current range
- 0.5V typical voltage threshold
- Sequencer outputs (OUT_)
- 0.3V maximum output voltage low
- 1µA maximum leakage current
- Fault input/output
- 0.3V maximum output voltage low
- 1µA maximum leakage current
- 0.5V typical input threshold
- POK
- 0.3V maximum output voltage low
- 1µA maximum leakage current
- DONE
- 0.3V maximum output voltage low
- 1µA maximum leakage current
- Timing
- ±15% POK reset timeout accuracy
- ±15% power good timer accuracy
- 6µs minimum on input pulse width
- 6µs minimum off input pulse width
- 6µs minimum external fault input pulse width
- 1µs maximum on/off/external fault input transient immunity
- 68µs to 92µs fault output hold timeout
- 1µs typical SET_ to fault/OUT_ low delay time
- 9µs typical external fault to OUT_ low delay time
- 9µs typical on to fault/OUT_ low delay time
- 9µs typical off to fault/OUT_ low delay time
- ESD ratings
- ±3000V Human Body Model (HBM), level 2
- ±500V FICDM, level C1
Simplified Application Diagram
Development Tools
Analog Devices Inc. ADM6840 Evaluation Kit
Monitors and sequences up to eight voltages with the onboard ADM6840 PMIC.