### IDT6167LA55PB: Technical Overview The **IDT6167LA55PB** is a high-speed Static Random Access Memory (SRAM) chip manufactured by Integrated Device Technology (IDT, now part of Renesas). It is designed using high-performance CMOS technology, offering a balance between speed and low power consumption. --- ### Core Specifications Below are the primary technical characteristics of the device: | Parameter | Specification | | :--- | :--- | | **Memory Type** | SRAM (Static RAM) | | **Organization** | 16,384 x 1 bit (16K x 1) | | **Access Time (Speed)** | 55 ns | | **Power Supply (Vcc)** | 5.0V ± 10% | | **Package Type** | Plastic DIP (300 mil) | | **Technology** | CMOS | | **Interface** | TTL Compatible | --- ### Functional Components The internal architecture of the IDT6167 consists of several key functional blocks: 1. **Memory Cell Array:** Organized as a 16K x 1 structure. Since it is "Static" RAM, it uses flip-flops to store each bit, meaning it does not require refreshing like DRAM. 2. **Address Decoders:** These circuits interpret the 14 address lines ($A_0$ to $A_{13}$) to select one specific bit out of the 16,384 available locations. 3. **Control Logic:** * **$\overline{CS}$ (Chip Select):** When HIGH, the chip enters a low-power standby mode. When LOW, the chip is active. * **$\overline{WE}$ (Write Enable):** Controls whether data is being read from or written to the memory. 4. **I/O Buffers:** Manages the Data Input ($D_{IN}$) and Data Output ($D_{OUT}$) pins. In this specific "x1" configuration, there are separate pins for input and output. --- ### Pin Configuration Summary | Pin Name | Function | Description | | :--- | :--- | :--- | | **$A_0 - A_{13}$** | Address Inputs | Used to select one of the 16,384 memory locations. | | **$\overline{CS}$** | Chip Select | Activates the device when LOW. | | **$\overline{WE}$** | Write Enable | Triggers a write cycle when LOW. | | **$D_{IN}$** | Data Input | The bit to be stored. | | **$D_{OUT}$** | Data Output | The bit being read. | | **$V_{CC} / GND$** | Power / Ground | 5V Power supply and reference ground. | --- ### Operating Modes The device operates in three primary states based on the control signals: 1. **Read Mode:** $\overline{CS}$ is LOW and $\overline{WE}$ is HIGH. The data at the selected address appears on the $D_{OUT}$ pin. 2. **Write Mode:** $\overline{CS}$ is LOW and $\overline{WE}$ is LOW. The data on the $D_{IN}$ pin is stored at the selected address. 3. **Standby Mode:** $\overline{CS}$ is HIGH. The device ignores other inputs and significantly reduces power consumption (ISB). --- ### Typical Applications Due to its 55ns access time and reliable CMOS build, this part was commonly used in: * Cache memory for legacy microprocessors. * Buffer memory for high-speed data communications. * Digital Signal Processing (DSP) systems. * Industrial embedded controllers requiring non-volatile-like stability without refresh cycles.