HOST

RPUP: 500Ω

VPUP: 3.13V to 5.25V

DUT1

SDQ

GND

DUT2

SDQ

GND

DUT3

SDQ

GND

Cable cap

1.7nF

Figure 6-5. Multiple Target Configuration

Successful communication implies the following sequence of instructions must be executed without failure:

1. Issue RESET in standard speed and check for presence pulse

2. Issue SEARCH ROM command to identify the IDs of responder devices on the SDQ bus.

3. Issue RESET in standard speed and check for presence pulse.

4. Select one of the targets by issuing MATCH ROM command with the specific ID of the responder device

identified from the SEARCH ROM command.

5. Issue MEMORY Commands to program or read from the memory.

6. Repeat steps 3, 4, and 5 for other responder devices on the SDQ bus.

6.5 Programming

6.5.1 Serial Communication

The host reads, programs, or checks the status of the TMF0008 through the command structure of the SDQ

interface as shown in Figure 6-6. The command structure includes ROM and MEMORY commands.

TMF0008

COMMAND LEVELS

ROM

COMMANDS

MEMORY

COMMANDS

READ ROM

MATCH ROM

SEARCH ROM

SKIP ROM

RESUME

OVERDRIVE SKIP ROM

OVERDRIVE MATCH ROM

COMMANDS

WRITE SCRATCHPAD

READ SCRATCHPAD

COPY SCRATCHPAD

READ MEMORY

EXTENDED READ MEMORY

Figure 6-6. Command Structure for the TMF0008

6.5.2 Initialization

The host always begins the transaction with the TMF0008 (responder) devices through an initialization process.

The Initialization process consists of the RESET and PRESENCE pulses. The host generates the RESET pulse,

while the responder devices acknowledges the RESET pulse with the PRESENCE pulse. The host resets the

TMF0008

SLVSIV3 – JULY 2025

www.ti.com

12

Submit Document Feedback

Copyright © 2025 Texas Instruments Incorporated

Product Folder Links: TMF0008