3.3 Dual Module Parallel Operation GUI Monitoring and Configuration Manual

The following table summarizes the key GUI-configurable and monitoring parameters for operating two MCPF1525M06 modules in parallel. Unless otherwise noted, settings should be applied to both modules using their respective I²C/PMBus addresses.

Table 3-1. Dual-Module Configuration Guidance
GUI/PMBus Setting	Configuration Guidance	Observation/Application
Device Role Assignment	U1 Host: I²C 0x10/PMBus 0x70; U2 Client: I²C 0x12/PMBus 0x72. If the Client is detected but not readable, manually assign the Client addresses in the GUI.	Enables independent access to both modules on the shared telemetry bus. Do not assign the hardware-configured Client as Host in the GUI.
OPERATION command	Configure consistently for both modules. For startup, command the Host ON first, then the Client.	To turn the modules ON/OFF through PMBus. Output turns ON only when both Host and Client are enabled and the Host is active first.
ON_OFF_CONFIG	Use consistent ON/OFF control settings for both modules.	If settings (PMBus OPERATION command, EN pin, or both) are mismatched, startup/shutdown behavior may not be synchronized.
VOUT_COMMAND	Configure both modules for the same VOUT setpoint. When changing VOUT dynamically, update Host first, then Client, using less than 200 mV difference per step	To program or dynamically adjust the shared output rail. Output voltage is controlled by the Host VOUT command. Large Host/Client command mismatch can cause regulation issues.
VOUT_MARGIN_HIGH/LOW	Use identical margin-high and margin-low settings for both Host and Client modules.	Supports rail margining testing feature, if voltage-margin command of both the Host and Client devices are aligned.
VIN_ON / VIN_OFF	Identical input UVLO thresholds set on both modules.	Ensures both modules enable and disable at the same input-voltage range
TON / TOFF Timing	Match startup and shutdown timing settings when used.	Aligns Host/Client startup and shutdown timing for controlled shared-rail sequencing.
Protection Limits: IOUT_OC_FAULT_LIMIT; VOUT_OV_FAULT_LIMIT ; OT_FAULT_LIMIT	Use matching values for both modules.	In a parallel system, the effective operating current/voltage/temperature may be constrained by the lower configured device limit.
Protection Response: IOUT_OC_FAULT_RESPONSE; VOUT_OV_FAULT_RESPONSE; OT_FAULT_RESPONSE	Configure the same response, such as hiccup (to restart) or latch-off (no restart), on both modules.	If one module is configured to restart and the other is configured not to restart, the parallel system may not restart as a complete power rail
SMBALERT_MASK/ALERT	Configure alert masking consistently on both modules. ALERT is part of the shared telemetry interface	Controls which warnings or faults assert the shared ALERT line
WRITE_PROTECT	Disable write protection before configuration; enable after final validation if required.	Prevents unintended register changes after setup.

Table 3-2. Dual-Module Monitoring Guidance
Monitoring Parameter	Observation/Application
Device Detection	Confirm two devices are listed in the GUI displaying their respective addresses (ADDR pin resistor configured).
READ_VIN, READ_VOUT	Check valid input voltage and output voltage reported by each module.
READ_IOUT	Displays current output from each module (expected to be half of total output current) and confirms current sharing between the modules.
READ_TEMPERATURE	Helps identify thermal imbalance or uneven current sharing.
STATUS_WORD / STATUS_BYTE	System Warning/Fault Status, First-level diagnostic check during startup, load testing, and fault recovery.
STATUS_IOUT, STATUS_VOUT, STATUS_INPUT, STATUS_TEMPERATURE	System Level and not Module level Warning/Fault Status, identifying specific nature of fault with respect to IOUT, VOUT, INPUT and TEMPERATURE operating points.