SLUSCC7C July 2016 – June 2018 TPS546C23
PRODUCTION DATA.
The VOUT_SCALE_LOOP command is equal to the feedback resistor ratio (RBIAS / (RBIAS + R1) in the configuration shown in Figure 25). This command is limited to only 3 possible options/ratios: 1 (default, no RBIAS needed), 0.5, and 0.25. Attempting to write a value unequal to one of these three options cause the device to set the cml bit in the STATUS_BYTE, and the ivd bit in the STATUS_CML registers. Additionally, SMBALERT is asserted and the value of VOUT_SCALE_LOOP remains unchanged. The contents of this register can be stored to nonvolatile memory using the STORE_DEFAULT_ALL command.
For loop slave device, this command cannot be accessed. Any writes to this command will be ignored. An attempt to read or write this command will result in a NACK’d command, the reporting of an IVC fault, and triggering of SMB_ALERT.
NOTE
Construct the feedback resistor ratio appropriately (see Table 1). If the
VOUT_SCALE_LOOP does not match the external feedback resistor ratio, the converter will regulate the output with the reference voltage as outlined in Equation 1 and Equation 2.
Program the VOUT_SCALE_LOOP setting before the output is turned on.
For the range checking to work properly and to avoid invalid data scenarios:
COMMAND | VOUT_SCALE_LOOP | |||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Format | Linear, two’s complement binary | |||||||||||||||
Bit Position | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Access | r | r | r | r | r | r | r | r | r | r | r | r | r | r/wE | r/wE | r/wE |
Function | Exponent | Mantissa | ||||||||||||||
Default Value | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 |