1. Overview

️· Chip: MSM6685
️· Type: Memory (likely a serial memory, based on the terminology)
️· Function: Allows sequential read and write operations, potentially for storing data in blocks.

2. Key Features & Functions (Pin Descriptions)

️· Serial Address Input (SAD): Input for addressing memory locations, allowing 13-bit addresses (A0-A12).
️· Serial Address Strobe (SAS): Clock signal to latch the address data into a register.
️· Address Transfer Strobe (TAS): Loads the internal address counter with the serially received address.
️· Read/Write Clock (RWCK): Core clock signal for read/write operations. The trailing edge triggers actions; incrementing the address happens on the rising edge.
️· Write Enable (WE): Selects between read mode (WE = High), write mode (WE = Low), and read-modify-write mode.
️· Data Input (DIN): Data is written to the memory using this pin.
️· Data Output (DOUT): Data is read from the memory using this pin. Maintains a high-impedance state when RWCK or Chip Select (CS) is high. Supports I/O sharing capabilities.
️· Chip Select (CS): Disables all inputs for parallel usage of multiple chips.
️· Test Pins (TEST): Must be held at specific logic levels during operation.

3. Electrical Specifications

️· Operating Voltage: 3.5V - 5.5V
️· Absolute Maximum Ratings: Standard limits to prevent damage.
️· DC Characteristics: Input/output leakage currents, voltage levels for high/low states.
️· AC Characteristics: Timing parameters for read/write cycles, access times, signal durations, setup/hold times. These define the speed at which the chip can be operated.

4. Operating Procedures & Considerations

️· Energization Sequence: Requires a 1ms pause after power-up for stabilization. A minimum of ten dummy read cycles with RWCK is also needed.
️· Power Supply Stability: The supply voltage should not fluctuate more than 1V within a 1000ms period to ensure reliable operation.
️· Surface Mount Considerations: Care must be taken during surface mounting due to heat and humidity sensitivity.

5. Package Information

️· Details about the physical package type are provided, along with instructions to contact Oki sales for proper mounting procedures.



Overall, the MSM6685 appears to be a specialized serial memory chip designed for sequential read and write operations, requiring careful handling during power-up, operation, and mounting.