1. General Information

️· Purpose: This document describes the electrical specifications and features of a power supply, likely designed for a server or similar application where power management and monitoring are crucial.
️· PMBus: The power supply supports the PMBus (Power Management Bus) protocol for communication and control.
️· LED Indicators: Uses a bi-color LED to indicate status:
- Green: Normal operation.
- Amber/Green: Warnings (hi-temp, slow fan).
- Amber: Failure (OVP, OTP, FAN FAULT).
️· Remote ON/OFF: Supports remote power control.
️· Mechanical Outline & Connectors: Details physical dimensions and connector part numbers for both input and output.

2. Electrical Specifications

️· Input Voltage: (Implicit - not stated, but typically a common range for server power supplies)
️· Output Voltage: 12V (main output), 3.3V (standby output)
️· Output Power: (Implicit - not stated, but likely in the hundreds of watts).
️· Power Supply Accuracy (see table at the end of the document, highlights important ranges where accuracy fluctuates)
️· Protection Features: Includes over-voltage protection (OVP), over-temperature protection (OTP), and fan fault detection.
️· Standby Output (3.3V): Provides a continuously available power source for monitoring and control circuits.
️· Current Sharing: Designed for use in redundant power configurations (n+n sharing) utilizing the IShare bus.

3. Communications (PMBus & I2C)

️· PMBus: Allows for real-time monitoring of power supply parameters (voltage, current, temperature, fan speed).
️· I2C: Supports I2C communication for address configuration and control.
- I2C Address: Configurable via A0 and A1 pins.
- SDA & SCL: Standard I2C data and clock lines.
️· Key PMBus Functionality:
- PSON_L: Power supply enable/inhibit signal.
- PS_INTERRUPT_L: Alert signal indicating a fault condition.
- ACOK: Active OK signal – indicates that the output voltage is within regulation.
- ISHARE: Current share bus for load sharing.
- PS_PRESENT_L: Power supply presence indicator.

4. Mechanical & Connectors

️· Output Connector: TE Connectivity 2-1926736-2
️· Mating Connector: TE Connectivity 2-1926739-5, or equivalent.
️· Pinout Details: The datasheet lists the function of each pin on the output connector (e.g., 12V output, ground, I2C data, control signals). This is *crucial* for proper connection.

5. Timing Specifications (Critical for System Integration)

️· Tsb\_On (2500 ms): Delay from AC power application to standby output regulation. *Important for systems needing quick standby power.*
️· Tsb\_ACOK (1500 ms): Delay from standby output to ACOK assertion.
️· Tsb\_Vout (1000 ms): Delay from standby to main output regulation.
️· TAC\_On\_Delay (3000 ms): Delay from AC application to main output regulation.
️· TPWR\_GOOD\_On (100-1000 ms): Delay from regulation to PWOK asserted.
️· TACOK\_Delay (20 ms): Delay from AC loss to ACOK deassertion. *Fast deassertion is important for failover scenarios.*
️· TPWR\_GOOD\_Hold-up (5 ms): Hold-up time for PWOK after AC loss.
️· TVout\_Hold-up (16 ms): Hold-up time for main output after AC loss.
️· Tsb\_Hold-up (25 ms): Hold-up time for standby output.
️· TPWR\_GOOD\_Off (1-700 ms): Delay from PWOK deassertion to output falling out of regulation.

Key Considerations & Potential Design Challenges:

️· Timing Budgets: Carefully consider the timing specifications during system design to ensure proper failover and power sequencing.
️· I2C Address Configuration: Understand how to configure the I2C address for communication.
️· Pinout: *Thoroughly* review the output connector pinout to avoid miswiring. Incorrect connections can damage the power supply or the connected equipment.
️· Load Sharing: If used in a redundant configuration, the current sharing functionality is critical for balanced load distribution.