The FM4428 is a 1K×8‑bit EEPROM storage card chip with write‑protect, PSC security and ISO‑7816 serial interface, described in this product manual.
The FM4428 is a 1 K × 8 bit EEPROM storage card chip designed by Fudan Microelectronics. It features a serial 3‑wire ISO‑7816 interface, write‑protect bits, a 2‑byte programming security code (PSC) and compatibility with SLE4428 devices.
The manual provides pin definitions, command formats, PSC authentication steps, electrical specifications, and contact information for sales and service locations. This manual is written in Chinese.
| Memory Capacity | 1024 × 8 bits (1 KByte) |
|---|---|
| Write‑Protect Bits | 1024 × 1 bit |
| Operating Voltage (VCC) | 4.5 – 5.5 V |
| Maximum Write/Erase Cycles | >100 000 cycles |
| Data Retention | >10 years |
| Interface | ISO‑7816 serial 3‑wire |
| Maximum Power Consumption | 60 mW |
| Input High Voltage (VIH) | 3.5 V |
| Input Low Voltage (VIL) | 0 – 0.8 V |
| Maximum Clock Frequency | 20 kHz |
Use the write command with the protect‑bit flag; the data is written and the write‑protect bit is set to make the cell read‑only.
First clear the error counter at address 1021, then write the two PSC bytes to addresses 1022 and 1023; authentication succeeds if the PSC matches.
VIH is 3.5 V (or VCC) and VIL ranges from 0 V to 0.8 V.
The chip operates with a clock up to 20 kHz.