Instruction Manual

MAX15303 PMBus Command Set User’s Guide
Page 7 of 52
ON_OFF_CONFIG
Reference:
Standard Command
Lockable:
Yes
Command Code:
0x02
Format:
Bit field
Data Bytes:
1
Units:
N/A
Transfer:
Read/Write Byte
Factory Value:
0x16 (see Description table)
Description/Notes:
See Section 12.2 of the PMBus Specification Part II.
Useful Values for the ON_OFF_CONFIG command:
0x00 Output always enabled (note: same as 0x01-0x0F)
0x10 Output always disabled (note: same as 0x11-0x13)
0x14 Ignore bit 7 of OPERATION
, require EN low to run, soft-off on loss of EN
0x15 Ignore bit 7 of OPERATION, require EN low to run, immediate-off on loss of EN
0x16 Ignore bit 7 of OPERATION, require EN high to run, soft-off on loss of EN (factory setting)
0x17 Ignore bit 7 of OPERATION, require EN high to run, immediate-off on loss of EN
0x18 Require bit 7 of OPERATION to run, ignore EN (note: same as 0x19-0x1B)
0x1C Require bit 7 of OPERATION and EN low to run, soft-off on loss of EN
0x1D Require bit 7 of OPERATION and EN low to run, immediate-off on loss of EN
0x1E Require bit 7 of OPERATION and EN high to run, soft-off on loss of EN
0x1F Require bit 7 of OPERATION and EN high to run, immediate-off on loss of EN
In general, odd values of ON_OFF_CONFIG that require a valid EN signal will have an immediate-off
shutdown when EN is not valid. Even values that require EN will have a soft-off shutdown when EN is
not valid.
After writing the ON_OFF_CONFIG command to enable the output, the PMBus master must either
wait for a time equal to (TON_DELAY + TON_RISE + 50ms), or wait for PG to assert, before sending
additional PMBus commands.
VIN_ON
Reference:
Standard Command
Lockable:
Yes
Command Code:
0x35
Format:
Linear
Data Bytes:
2
Units:
V
Transfer:
Read/Write Word
Factory Value:
0xCB00 (6.0V)
Description/Notes:
See Section 14.5 of the PMBus Specification Part II.
The MAX15303 hardware has 8-bit resolution for the minimum input voltage required for regulation,
to a maximum value of ≈14.75V.
The desired value of VIN_ON is retained in memory, regardless limitations imposed by the 8-bit fault
limit resolution, but the read-back value is based on actual hardware register settings.
VIN_OFF
Reference:
Standard Command
Lockable:
Yes
Command Code:
0x36
Format:
Linear
Data Bytes:
2
Units:
V
Transfer:
Read/Write Word
Factory Value:
0xCAC0 (5.5V)