The **LCMXO2-640UHC-4QN84C** (part of the Lattice MachXO2 family) is an ultra-low-power, instant-on Flash-based PLD (Programmable Logic Device). It is widely used for system control, interface bridging, and power management due to its small footprint and built-in features. --- ### 1. Part Number Breakdown Understanding the nomenclature helps identify the specific capabilities of this component: | Prefix/Code | Meaning | Description | | :--- | :--- | :--- | | **LCMXO2** | Family Series | MachXO2 (Bridging & Control applications) | | **640** | LUT Count | Approximately 640 Look-Up Tables (Logic capacity) | | **U** | Ultra Low Power | Optimized for minimal power consumption | | **HC** | Voltage/Speed | High Performance / 2.5V - 3.3V core voltage | | **4** | Speed Grade | Indicates the timing performance (4 is standard) | | **QN84** | Package Type | 84-pin QFN (Quad Flat No-lead) | | **C** | Temp Grade | Commercial (0°C to +85°C) | --- ### 2. Key Technical Specifications The MachXO2-640 is designed to replace multiple discrete logic chips on a PCB. * **Logic Density:** 640 LUTs (Look-Up Tables). * **User I/O:** 64 programmable I/O pins. * **Embedded Memory:** 18 Kbits of SysMEM EBR (Embedded Block RAM). * **Flash Memory:** 64 Kbits of User Flash Memory (UFM) for non-volatile data storage. * **Configuration:** On-chip Flash allows for "Instant-on" capability (the chip functions within microseconds of power-up). * **Hardened IP:** Includes dedicated hardwired I2C, SPI, and Timer/Counter blocks to save logic cells. --- ### 3. Core Architecture Features #### A. Hardened Functions Unlike standard FPGAs where you must use logic gates to build an I2C controller, the MachXO2 has **Hardened IP**. This means it has physical circuits for: * Two I2C interfaces. * One SPI interface. * A 16-bit Timer/Counter. #### B. Power Management The "U" (Ultra Low Power) designation signifies that the device can operate in "Static Mode," consuming as little as **sub-100µA** of standby current, making it ideal for battery-operated handheld devices. #### C. WISHBONE Bus It supports the WISHBONE internal bus architecture, allowing for easy connection between the logic fabric and the hardened IP cores. --- ### 4. Typical Applications The LCMXO2-640 is commonly found in: 1. **System Control:** Power sequencing, reset signal generation, and glue logic. 2. **Interface Bridging:** Converting signals between different protocols (e.g., I2C to Parallel). 3. **I/O Expansion:** Adding more GPIOs to a microcontroller that has run out of pins. 4. **Display Driving:** Handling small character LCD or LED matrix timing. --- ### 5. Programming & Development To design for this chip, you typically use: * **Software:** Lattice Diamond® design software. * **Languages:** VHDL or Verilog. * **Programming:** JTAG interface or through the hardened I2C/SPI ports (In-System Programming).