Overview
The ADM1172-2AUJZ-RL7, produced by Analog Devices Inc., is a hot swap controller designed to safely enable the removal and insertion of a printed circuit board into a live backplane. This device ensures that the board is protected from excess currents during the insertion and removal process. It operates over a supply voltage range of 2.7 V to 16.5 V and features an undervoltage lockout circuit to ensure proper operation once the supply voltage reaches a sufficient level. The ADM1172-2AUJZ-RL7 uses an external N-channel power MOSFET with a current control loop to monitor and limit the load current through a sense resistor.
Key Specifications
| Parameter | Value |
|---|---|
| Supply Voltage Range | 2.7 V to 16.5 V |
| Package Type | TSOT-23-8 |
| Operating Temperature | -40°C to 125°C |
| Current Limiting | 50 mV/RSENSE |
| UVLO Threshold | Internal UVLO circuit |
| ON (ON-CLR) Pin Threshold | 1.3 V with 50 mV hysteresis |
| Power-Fail Comparator Reference | 0.6 V internal reference |
Key Features
- Automatic retry or latch-off during current fault (ADM1172-2AUJZ-RL7 latches off)
- Undervoltage lockout (UVLO) circuit
- Current control loop with external sense resistor
- Internal charge pump to enhance the gate of the N-channel FET
- Power-fail comparator with 0.6 V internal reference
- Timer function controlled by the TIMER pin capacitor
- Glitch filter on the ON (ON-CLR) pin
Applications
- Hot swap board insertion: line cards, RAID systems
- Industrial high-side switches/circuit breakers
- Electronic circuit breakers
Q & A
- What is the primary function of the ADM1172-2AUJZ-RL7? The primary function is to safely enable the removal and insertion of a printed circuit board into a live backplane.
- What is the supply voltage range of the ADM1172-2AUJZ-RL7? The supply voltage range is 2.7 V to 16.5 V.
- What type of package does the ADM1172-2AUJZ-RL7 come in? It comes in a TSOT-23-8 package.
- How does the ADM1172-2AUJZ-RL7 handle overcurrent conditions? It limits the current to 50 mV/RSENSE and can either retry or latch off depending on the model.
- What is the purpose of the undervoltage lockout (UVLO) circuit? The UVLO circuit ensures that the device does not operate until the supply voltage reaches a sufficient level.
- How is the timer function controlled in the ADM1172-2AUJZ-RL7? The timer function is controlled by the TIMER pin capacitor.
- What is the role of the power-fail comparator in the ADM1172-2AUJZ-RL7? The power-fail comparator compares the voltage on the PFI pin with an internal 0.6 V reference and presents the output on the PFO pin.
- Can the ADM1172-2AUJZ-RL7 be reset after a fault? Yes, toggling the ON (ON-CLR) pin resets a latched fault.
- What are some common applications of the ADM1172-2AUJZ-RL7? Common applications include hot swap board insertion, industrial high-side switches, and electronic circuit breakers.
- How does the ADM1172-2AUJZ-RL7 protect against inrush current? It monitors the inrush current through an external sense resistor and limits it to prevent damage.
