• Status: Draft schematic start
• Device: Programmable isolated-output CV/CC bench/lab supply architecture targeting 0.5–100 V output, 0–40 A current limit, and 3 kW maximum output power.
• Current scope: full four-phase system schematic. Mean Well AC/DC power modules, matrix contactors, high-current fuses, busbars, enclosure wiring, fans, and emergency-stop mains hardware are represented as off-board interfaces rather than PCB-mounted parts.

• Prototype/validation platform for a high-power programmable DC supply.
• Intended development sequence starts with schematic capture and design review, followed by one-phase power-stage validation before committing to a full 3 kW layout and enclosure.

• Generate programmable CV and CC output from 0.5 V to 100 V.
• Deliver up to 40 A below the power-limit knee, constrained to 3 kW maximum.
• Switch between LOW bus mode (~26.4 V, four supplies in parallel) and HIGH bus mode (~105.6 V, four supplies in series) with output interruption.
• Provide hard/firmware protection for overcurrent, overvoltage, phase imbalance, overtemperature, failed contactor states, and discharge/precharge sequencing.

• Four interleaved synchronous buck phases at 100 kHz/phase.
• Off-board supply/contactors modeled via connectors and control/feedback interfaces.
• C2000 controller with PWM, trip-zone, ADC, and sigma-delta filter inputs.
• Isolated per-phase current measurement plus independent total-current hardware trip.
• Precision monitoring ADC for calibration and telemetry.
• Dedicated auxiliary rails independent of the reconfigurable high-power bus.

Diagram

• Off-board power-source interface: four 24 V/960 W AC/DC modules adjusted to 26.4 V, represented by module terminal/control connectors.
• Off-board contactor matrix: series/parallel mode contactors, output contactor, precharge bypass, and LV capacitor-bank contactor represented by coil-drive and auxiliary-feedback connectors.
• Four-phase buck stage: 200 V MOSFET half-bridges, gate drivers, inductors, phase shunts, local input capacitors, bootstrap networks, and output bus combining.
• Sensing/protection: per-phase isolated delta-sigma modulators, total-current Hall sensor/comparator, remote/local voltage sense, bus OVP/brake, output discharge.
• Control: TI C2000 controller, precision ADC, isolated CAN, watchdog, debug/programming.
• Auxiliary rails: off-board 24 V auxiliary input; onboard 12 V, 5 V, and 3.3 V regulators.

• High-power bus: BUS+, BUS− from off-board matrix.
• Output: OUT+, OUT− high-current terminals and remote-sense pair.
• Off-board controls: AC/DC enable, contactor coil drives, auxiliary contact feedback, current-share relay controls.
• Communications: isolated CAN.
• Debug: C2000 programming/debug interface.

• Main output: ≤3 kW, up to 100 V and 40 A depending on setpoint.
• Auxiliary input: 24 V off-board supply, target ~150 W class.
• Onboard rails: 12 V gate-driver rail, 5 V analog/sensor/relay logic rail, 3.3 V MCU/digital rail.

• Professional SMD PCB for control and power electronics.
• High-current AC/DC modules, contactors, fuses, copper busbars, mains wiring, fans, and enclosure hardware are off-board.
• High-current PCB copper, creepage/clearance, thermal relief, gate-drive layout, current-sense Kelvin routing, and snubber tuning require prototype validation.

• Four synchronized PWM phases with 0/90/180/270° phase offsets.
• Hardware trip inputs must disable PWM without firmware latency.
• ADC/SDFM measurement channels for phase currents, total current, bus voltage, output voltage, temperatures, contactor feedback, and auxiliary rail telemetry.
• Sequenced state machine for precharge, range changes, output contactor, discharge, and fault handling.

• Board size, enclosure, airflow, heatsinking, busbar interfaces, and connector locations are TBD.
• Layout must treat switch nodes, gate loops, shunt Kelvin signals, isolated boundaries, and high-current planes as critical.

• Use four fixed AC/DC modules off-board rather than designing the mains front end on the PCB.
• Use two bus modes only: LOW 4P and HIGH 4S.
• Keep contactors off-board and represent them through control/feedback connectors.
• Use one common controller supervising all four phases rather than paralleling independent converters.
• Build the schematic for the full system now, but validate a one-phase prototype before full-power assembly.

• Mains AC handling remains outside the PCB/enclosure wiring model for this schematic pass.
• The first schematic revision is architectural and will require datasheet-backed refinement, loop compensation calculation, thermal analysis, and prototype test results.
• Exact connector families and board mechanical constraints are not yet specified.

• Initial specification created from the provided Rev A reference implementation and user request to start the full four-phase schematic with power modules/contactors off-board.