SLUSBO6C JANUARY 2014 – October 2018 TPS40425
PRODUCTION DATA.
The PMBus specification requires that each device connected to the PMBus have a unique address on the bus. The TPS40425 device has 64 possible addresses (0 through 63 in decimal) that can be assigned by connecting resistors from the ADDR0 and ADDR1 pins to AGND. The address is set in the form of two octal (0-7) digits, one digit for each pin. ADDR1 is the high-order digit an ADDR0 is the low-order digit.
During PMBus communication, the PMBus address of TPS40425 device is the concatenation of '0b'+ADDR1+ADDR0. The R/W bit of PMBus protocol is added at the end of address to make it net 8-bit wide.
Table 7 shows the E96 series resistors suggested for each digit value.
CAUTION
Use only the resistor values listed in Table 7 to correctly set PMBus address. Using any other value might result in an incorrect PMBus address.
DIGIT | RESISTANCE (kΩ) |
---|---|
0 | 8.45 |
1 | 16.2 |
2 | 25.5 |
3 | 37.4 |
4 | 54.9 |
5 | 84.5 |
6 | 133 |
7 | 200 |
The TPS40425 also detects values that are out of range on the ADDR0 and ADDR1 pins. If either pin is detected as having an out of range resistance connected to it, the device continues to respond to PMBus commands, but at address 127, which is outside of the possible programmed addresses. It is possible but not recommended to use the device in this condition, especially if other TPS40425 devices are present on the bus or if another device could possibly occupy the 127 address.
NOTE
Some addresses are reserved by SMBus specification and must not be used by or assigned to SMBus slave device. Refer to SMBus specification for more information.