Overview
The ADM1278-1BCPZ-RL, produced by Analog Devices Inc., is a hot swap controller designed to enable the safe insertion or removal of a circuit board from a live backplane. This component integrates multiple functions, including current, voltage, power, and temperature monitoring, making it a comprehensive solution for power system management.
It features a 12-bit analog-to-digital converter (ADC) accessible via a PMBus™ interface, allowing for detailed monitoring of the power supply. The device also includes overvoltage (OV) and undervoltage (UV) protection, as well as a fast internal overcurrent detector to ensure robust protection against various fault conditions.
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, TA = −40°C to +85°C | |
| 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 | ||
| UV PIN Input Current | IUV | 50 | nA | UV ≤ 3.6 V | ||
| Input High Voltage | VIH | 2.0 | V | |||
| Input Low Voltage | VIL | 0.8 | V | |||
| Output Low Voltage | VOL | 0.4 | V | IOL = 4 mA | ||
| Leakage Current | 1 | μA | ||||
| Data Rate | 1 | MHz |
Key Features
- Hot Swap Capability: Allows safe insertion or removal of a circuit board from a live backplane.
- Integrated 12-bit ADC: Monitors current, voltage, power, and temperature via PMBus™ interface.
- Current Limiting: Controls the gate voltage of an external N-channel FET to limit current through the sense resistor.
- Overcurrent Protection: Fast internal overcurrent detector responds within 320 ns to short-circuit events.
- Overvoltage and Undervoltage Protection: Programmed using external resistor dividers on the UV and OV pins.
- Power Foldback Scheme: Controls power dissipation in the MOSFET during power-up and fault conditions.
- RETRY Pin Configuration: Can be set for automatic retry or latch-off in case of overcurrent faults.
- PWRGD Signal: Indicates when the output supply is valid.
Applications
- Data Centers and Cloud Infrastructure: For hot-swappable power supplies and server boards.
- Telecommunications Equipment: To ensure continuous operation during board replacements.
- Industrial Automation: For reliable power management in industrial control systems.
- Medical Devices: Where uninterrupted power supply is critical.
- High-Reliability Systems: Such as aerospace and defense applications requiring robust power management.
Q & A
- What is the primary function of the ADM1278-1BCPZ-RL?
The primary function is to enable hot swapping of circuit boards in live backplanes while providing current, voltage, power, and temperature monitoring.
- What interface does the ADM1278 use for monitoring?
The device uses a PMBus™ interface for monitoring current, voltage, power, and temperature.
- How does the ADM1278 protect against overcurrent conditions?
It features a fast internal overcurrent detector that responds within 320 ns and controls the gate voltage of an external N-channel FET to limit current.
- What is the operating voltage range of the ADM1278-1BCPZ-RL?
The operating voltage range is from 4.5 V to 20 V.
- Does the ADM1278 have overvoltage and undervoltage protection?
Yes, it has overvoltage and undervoltage protection programmed using external resistor dividers on the UV and OV pins.
- What is the purpose of the RETRY pin on the ADM1278?
The RETRY pin can be configured for automatic retry or latch-off in case of overcurrent faults.
- How does the ADM1278 manage power dissipation during faults?
It uses a constant power foldback scheme to control power dissipation in the MOSFET during power-up and fault conditions.
- What is the significance of the PWRGD signal in the ADM1278?
The PWRGD signal indicates when the output supply is valid.
- In what package is the ADM1278-1BCPZ-RL available?
The device is available in a 32-lead LFCSP (Lead Frame Chip Scale Package) with an exposed pad.
- Is the ADM1278-1BCPZ-RL RoHS compliant?
Yes, the device is RoHS compliant.
