The **TC5501P** is a legacy semiconductor component, specifically a **1,024-word by 1-bit (1K x 1) Static Random Access Memory (SRAM)** chip. It was manufactured by Toshiba using CMOS technology, which was notable at the time of its release for low power consumption compared to NMOS alternatives. --- ### 1. Key Technical Specifications Below are the primary electrical and functional characteristics of the TC5501P: | Feature | Specification | | :--- | :--- | | **Memory Capacity** | 1,024 Bits (1,024 x 1) | | **Technology** | CMOS (Complementary Metal-Oxide-Semiconductor) | | **Package Type** | 16-pin Dual In-line Package (DIP) | | **Supply Voltage (Vcc)** | 5V (Typical) | | **Access Time** | Variable (typically 450ns to 650ns depending on suffix) | | **Operating Current** | Very low (Microwatts in standby) | --- ### 2. Pin Configuration (16-Pin DIP) The TC5501P uses a standard layout for 1K SRAMs of its era. * **A0 - A9**: Address Inputs (used to select one of the 1,024 memory locations). * **D_in / D_out**: Data Input and Data Output pins (separate lines). * **R/W (Read/Write)**: Controls whether data is being read from or written to the chip. * **CE (Chip Enable)**: Activates the chip. When high (or inactive), the chip enters a low-power standby mode. * **Vcc / GND**: Power supply (+5V) and Ground. --- ### 3. Core Functional Characteristics #### A. Static Operation Unlike DRAM (Dynamic RAM), the TC5501P is **Static**. It does not require a refresh clock to maintain data integrity as long as power is supplied. This makes the interface circuitry much simpler for 8-bit microprocessors. #### B. Low Power Consumption Being a CMOS device, its primary advantage was the extremely low standby current. This made it ideal for: * Battery-backed memory systems. * Handheld electronic devices. * Portable instrumentation. #### C. Separate I/O Unlike modern SRAMs that often multiplex data lines (I/O 1-8), the TC5501P features **separate pins** for Data In and Data Out. This is common in very early 1-bit architecture memory chips. --- ### 4. Typical Applications Historically, the TC5501P was found in: 1. **Early Microcomputers:** Used as cache or main memory in 4-bit and 8-bit systems. 2. **Industrial Controllers:** Storing configuration data that needed to be preserved via a small battery. 3. **Synthesizers/Audio Gear:** Storing patch data or sequences.