The FANUC A16B-3200-0010 is a multilayer PCB containing the central processor unit (CPU) for FANUC Series 0i, 16i, and 18i controller models. This card manages real-time axis interpolation, programmable logic control (PMC), and communication with servo amplifiers and I/O modules.
The board is built around a 32-bit RISC processor running at 64 MHz. It includes 4 MB of flash ROM for system firmware and option functions, plus 2 MB of SRAM for part programs, tool offsets, and parameters. A lithium battery (sold separately) maintains SRAM content for up to five years when the main power is off.
Onboard components include a PMC control chip for handling up to 1024 digital inputs and 1024 outputs, two high-speed serial servo interfaces (FSSB), and a dedicated analog spindle interface. A PCI bridge connects to optional boards such as the A16B-3200-0020 (analog I/O) or A16B-3200-0030 (encoder interface).
Seven status LEDs on the board provide immediate feedback: green for power, yellow for CPU active, red for watchdog fault, and four bi-color LEDs for FSSB communication health. The built-in self-diagnostic program checks RAM, ROM, and bus integrity at every power-on. Diagnostic codes are displayed on the CNC screen or the board’s 7-segment display.

This CPU card is a direct replacement for FANUC A16B-3200-0010 variants with firmware version 9.4 or higher. It works with A06B servo drives, A02B operator panels, and I/O link modules. When replacing an older board, the user must transfer the SRAM data via a memory card or RS-232 backup.
The board operates from 5 V DC (±5%) supplied by the CNC backplane, consuming about 1.2 A. Temperature range: 0°C to 55°C. Conformal coating protects against dust and humidity (10% to 90% non-condensing). Mean time between failures (MTBF) is rated at over 100,000 hours under normal industrial conditions.



