Overview
The ADM1278-1AACPZ-RL, produced by Analog Devices Inc., is a hot swap controller designed to facilitate the safe insertion and removal of circuit boards from a live backplane. This device integrates a 12-bit analog-to-digital converter (ADC) and supports PMBus™ interface for monitoring current, voltage, power, and temperature. It ensures robust protection and control over the power path, including overcurrent, overvoltage, and undervoltage protection, making it a reliable component for various power management applications.
Key Specifications
| Parameter | Symbol | Min | Typ | Max | Unit | Test Conditions/Comments |
|---|---|---|---|---|---|---|
| Operating Voltage Range | VCC | 4.5 | 20 | V | VCC ≥ VHS+, VHS+ = 2 V to 20 V | |
| Undervoltage Lockout | UVLO | 2.4 | 2.7 | V | VCC rising | |
| Undervoltage Hysteresis | 90 | 120 | mV | |||
| Quiescent Current | ICC | 5.5 | mA | GATE on and power monitor running | ||
| Input High Voltage (SDA, SCL) | VIH | 1.1 | V | |||
| Input Low Voltage (SDA, SCL) | VIL | 0.8 | V | |||
| Output Low Voltage (SDA, SCL) | VOL | 0.4 | V | IOL = 4 mA | ||
| ADC Accuracy | ±0.7% | % | For ADM1278-1A model |
Key Features
- Hot swap capability allowing safe insertion and removal of circuit boards from a live backplane.
- Integrated 12-bit ADC for current, voltage, power, and temperature monitoring via PMBus™ interface.
- Current limiting and foldback to protect the external MOSFET during power-up and fault conditions.
- Fast overcurrent detection and response within 320 ns.
- Overvoltage (OV) and undervoltage (UV) protection programmed using external resistor dividers.
- PWRGD signal for output supply validation.
- RETRY pin for automatic retry or latch-off configuration in case of overcurrent faults.
Applications
The ADM1278-1AACPZ-RL is suitable for a variety of applications requiring robust power management and monitoring, including:
- Data centers and server systems.
- Telecommunication equipment.
- Industrial power systems.
- High-reliability power supplies.
Q & A
- What is the primary function of the ADM1278-1AACPZ-RL? The primary function is to act as a hot swap controller, allowing safe insertion and removal of circuit boards from a live backplane while monitoring and controlling power parameters.
- What interface does the ADM1278-1AACPZ-RL use for monitoring? It uses the PMBus™ interface for monitoring current, voltage, power, and temperature.
- How does the ADM1278-1AACPZ-RL protect against overcurrent conditions? It features a fast internal overcurrent detector that responds within 320 ns and limits the current through the sense resistor by controlling the gate voltage of an external N-channel FET.
- What is the ADC accuracy of the ADM1278-1A model? The ADC accuracy of the ADM1278-1A model is ±0.7%.
- How is overvoltage and undervoltage protection implemented? Overvoltage and undervoltage protection is implemented using external resistor dividers on the UV and OV pins.
- What is the purpose of the PWRGD signal? The PWRGD signal is used to detect when the output supply is valid.
- What is the role of the RETRY pin? The RETRY pin can be configured for automatic retry or latch-off when an overcurrent fault occurs.
- In what package is the ADM1278-1AACPZ-RL available? It is available in a 32-lead LFCSP package.
- What is the operating voltage range of the ADM1278-1AACPZ-RL? The operating voltage range is from 4.5 V to 20 V.
- What is the quiescent current of the ADM1278-1AACPZ-RL? The quiescent current is 5.5 mA when the GATE is on and the power monitor is running.
