JAJSMF5B september 2022 – june 2023 TPS25990
PRODUCTION DATA
PSU_VOLTAGE is a manufacturer-specific command for configuring or reading an 8-bit data corresponding to the input power supply voltage for implementing the input cable fault detection feature.
This command uses the PMBus® read or write byte protocol.
Sending a value to the PSU_VOLTAGE register:
Real world value of input power supply voltage in V is converted into a 10-bit binary data through PMBus® DIRECT format conversion using Equation 20 and the 'm', 'b', & 'R' coefficients corresponding to READ_VIN in Table 8-67. Hexadecimal value corresponding to the eight least significant bits from this 10-bit binary data needs to be written in the PSU_VOLTAGE register.
Interpreting the received values from the PSU_VOLTAGE register:
One byte of hexadecimal data read from the PSU_VOLTAGE register needs to be converted into a 10-bit binary data by appending the READ_VIN[9:8] bits to the left side. The hexadecimal value corresponding to this 10-bit binary data needs to be converted to a real world value of input power supply voltage in V through PMBus® DIRECT format conversion using Equation 19 and the 'm', 'b', & 'R' coefficients corresponding to READ_VIN in Table 8-67.
The details of this register are shown in Table 9-69.
Bit | Name |
Description |
READ_VIN[9:8] |
Minimum Value |
Maximum Value |
Default Value |
Access |
---|---|---|---|---|---|---|---|
7:0 |
PSU_VOLTAGE |
Nominal input power supply voltage |
00 |
0x00h (0 V) |
0xFFh (4.86 V) |
0x9Dh (2.99 V) |
Read/Write |
01 |
0x00h (4.87 V) |
0xFFh (9.73 V) |
0x9Dh (7.86 V) | ||||
10 |
0x00h (9.75 V) |
0xFFh (14.61 V) |
0x9Dh (12.74 V) | ||||
11 |
0x00h (14.63 V) |
0xFFh (19.48 V) |
0x9Dh (17.62 V) |
A write command to this register should be preceded by the MFR_WRITE_PROTECT command to unlock the device first to prevent accidental accidental/spurious writes.