Overview
The ADM1278-1ACPZ-RL is a hot swap controller produced by Analog Devices Inc. This component is designed to enable the safe insertion and removal of circuit boards from a live backplane, ensuring protection against various fault conditions. The ADM1278 features integrated current, voltage, power, and temperature monitoring through a 12-bit analog-to-digital converter (ADC), accessible via a PMBus™ interface. It controls the gate voltage of an external N-channel FET to limit the load current and protects the FET during power-up and 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 | |
| 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
- Integrated 12-bit ADC for current, voltage, power, and temperature monitoring via PMBus™ interface.
- Current limiting and foldback to protect the external N-channel FET during power-up and fault conditions.
- Fast internal overcurrent detector responding within 320 ns and 1500 mA pull-down device for fast FET response.
- Overvoltage (OV) and undervoltage (UV) protection programmable using external resistor dividers.
- PWRGD signal for detecting valid output supply.
- RETRY pin configurable for automatic retry or latch-off in case of overcurrent faults.
- Programmable features include auto retry, current limit, fault timeout, latched fault, OVP, and slew rate.
Applications
The ADM1278-1ACPZ-RL is suitable for various applications requiring hot swap capabilities, such as:
- Data centers and server systems where boards need to be inserted or removed without disrupting the system.
- Telecommunication equipment and networking devices that require reliable power management.
- Industrial control systems and automation where hot swap functionality is crucial.
Q & A
- What is the primary function of the ADM1278-1ACPZ-RL?
The primary function is to enable safe insertion and removal of circuit boards from a live backplane while providing current, voltage, power, and temperature monitoring and protection.
- What interface does the ADM1278 use for monitoring parameters?
The ADM1278 uses a PMBus™ interface for monitoring parameters such as current, voltage, power, and temperature.
- How does the ADM1278 protect the external N-channel FET?
The ADM1278 protects the external N-channel FET by limiting the current through the sense resistor and using a constant power foldback scheme during power-up and fault conditions).
- What is the response time of the internal overcurrent detector?
The internal overcurrent detector responds within 320 ns).
- Can the ADM1278 be configured for automatic retry or latch-off in case of faults?
Yes, the RETRY pin can be configured for automatic retry or latch-off in case of overcurrent faults).
- What are the programmable features of the ADM1278?
The programmable features include auto retry, current limit, fault timeout, latched fault, OVP, and slew rate).
- What is the operating voltage range of the ADM1278?
The operating voltage range is from 4.5 V to 20 V).
- How does the ADM1278 monitor the output supply validity?
The ADM1278 uses a PWRGD signal to detect when the output supply is valid).
- What type of package does the ADM1278-1ACPZ-RL come in?
The ADM1278-1ACPZ-RL comes in a 32-lead LFCSP package).
- What are some typical applications of the ADM1278?
Typical applications include data centers, telecommunication equipment, and industrial control systems where hot swap functionality is required).
