Basic Information

• Part Number: DF8203490‑A0

• Equivalent Models: JANCD‑MM20 (Rev. B), JANCD‑PC20

• Manufacturer: Yaskawa Electric (Japan)

• Type: CNC Main Memory / CPU Processor PCB

• Status: Obsolete; available as new surplus, refurbished, used

• Application: Yaskawa Yasnac J300 / J500 CNC & Motoman XRC robots

Specifications

• Power Supply: 5 V DC (logic), ±12 V DC (interfaces)

• Memory: Onboard RAM/ROM for CNC firmware and motion data

• Bus Interface: Yaskawa proprietary system bus (JANCD backplane)

• Dimensions: ~260 × 150 × 30 mm

• Weight: ~0.6 kg

• Operating Temp: 0 °C to +55 °C

• Mounting: Rack‑mount in CNC/XRC controller cabinet

Key Functions

• System Memory: Stores CNC OS, user programs, parameters, and motion data

• CPU Extension: Works with JANCD‑CP11 (DF8203078) as a dedicated motion/co‑processor

• Data Processing: Handles CNC interpolation, servo control algorithms, and I/O data exchange

• System Expansion: Enables additional axis control and memory capacity for complex machining

Compatibility

• Fits: Yasnac J300/J500 CNC, Motoman XRC robot controllers (UP6, HP20, etc.)

• Works with: JANCD‑CP11 (DF8203078), JANCD‑1003D (DF8203297) boards

• Not compatible: NX100, DX100, FS100 robot controllers or later CNC systems

Common Issues & Replacement

• Typical Failures: DRAM/ROM chip failure, battery backup loss, trace corrosion

• Replacement: Match DF8203490‑A0, JANCD‑MM20 Rev. B or JANCD‑PC20 markings

• Handling: Use ESD protection; replace onboard battery to preserve parameters