MP174GJ-Z IAKCG IAKCH Primary Side Regulator - Power Supply Solution

MP174GJ-Z Primary Side Regulator with Integrated 700V MOSFET for PSU Repair

The MP174GJ-Z (marked IAKCG or IAKCH) is a primary-side regulator IC that integrates a 700V power MOSFET with a constant-voltage (CV) controller in a compact SOT23-5 package. It supports Buck, Buck-Boost, Boost and Flyback topologies and provides accurate CV regulation without the need for an optocoupler, which simplifies the schematic and reduces the BOM on low-power off-line supplies.

With green-mode operation for improved light-load efficiency, the MP174GJ-Z is well suited to the auxiliary supplies inside ASIC miner PSUs, backup-power modules and home-appliance power stages.

Specifications

Where the MP174GJ-Z fits in an ASIC miner PSU

Inside ASIC miner power supplies, the MP174GJ-Z is the kind of IC used in the auxiliary or housekeeping flyback that powers the PFC controller, the gate drivers and the fan circuits. Because it integrates its own 700V MOSFET, no separate primary switch is required — which is why the IC and the small flyback transformer next to it are the first things to inspect when the PSU shows no standby rail despite a charged bulk capacitor.

Compatibility

Use as a direct replacement for MP174GJ-Z sockets marked IAKCG or IAKCH on PSU control boards. The SOT23-5 footprint is industry-standard but pinouts vary across families — confirm the marking on the failed IC matches before fitting.

Common failure symptoms

• PSU dead with no auxiliary rail despite a healthy bulk DC bus
• Standby LED on the PSU never lights up after AC connection
• Burn mark on the SOT23-5 IC adjacent to the small flyback transformer
• Hiccup behavior at start-up with the main PSU never enabling
• Short between the drain pin and ground when the IC is removed

Frequently asked questions

What do the IAKCG and IAKCH markings mean?

IAKCG and IAKCH are the top markings used to identify the MP174GJ-Z on its SOT23-5 body. Both are the same base device; the suffix typically indicates production lot or revision.

Do I still need an optocoupler?

No. The MP174GJ-Z performs constant-voltage regulation from the primary side, removing the need for a secondary-side reference and optocoupler — which is one of the reasons it appears in compact auxiliary supplies.

Is the integrated MOSFET really 700V?

Yes. The integrated power MOSFET is rated 700V, giving comfortable headroom on 220-277V AC mains operation.

Can I use it in other topologies than flyback?

Yes — Buck, Buck-Boost, Boost and Flyback are all supported. The actual schematic determines which topology is active.

Related products

• TNY288DG Off-Line Switcher SOP7
• SPX5205M5-L-5.0 LDO 5V Regulator SOT-23-5
• 3PCS01 ICE3PCS01G PFC IC for Avalon PSU3300
• MDF5N50F 500V N-Channel MOSFET Avalon PSU

Contact contact@lys-sz.com for volume pricing or compatibility questions. Worldwide shipping from our Shenzhen warehouses. DDP available for US and EU customers.