Supported Pmbus™ Commands; Controlling The Module Outputs Of The Unit; Modes Of Operation - TDK-Lambda QM Series Application Notes

Supported PMBus™ Commands
See references [1], [2], and [3] for details of the PMBus™ command structure and transaction types.
Command Name
OPERATION
ON/OFF CONFIG
CLEAR FAULTS
CAPABILITY
STATUS BYTE
STATUS_FANS_1_2
READ
TEMPERATURE
READ FANSPEED 1
READ FANSPEED 1
PMBus™ REVISION
MANUFACTURER ID
MANUFACTURER
MODEL
MANUFACTURE
DATE
SERIAL NUMBER
RUNTIME
POWER CYCLE
COUNT
SOFTWARE VERSION
NUMBER
More details for each command are given in the sections below.

Controlling the Module Outputs of the Unit

Modes of Operation

There are 6 distinct modes of operation:
1. Module outputs enabled when Input Power is present (factory default)
2. Module outputs enabled when commanded to by the PMBus™ Operation Command
3. Module outputs enabled when the PMBus™ Control Pin is HIGH
4. Module outputs enabled when the PMBus™ Control Pin is LOW
5. Module outputs enabled when commanded to by the PMBus™ Operation Command AND the PMBus™
Control Pin is HIGH
6. Module outputs enabled when commanded to by the PMBus™ Operation Command AND the PMBus™
Control Pin is LOW
The active mode of operation is selected using the On/Off Configuration Command (02h) described below.
From the factory, units are programmed to default to mode (1) so that units may be used without a PMBus™
connection.
N.B. The output state of all modules fitted in a QM unit are switched together. Individual control of the separate
modules within a QM unit is not possible. If multiple QM units (maximum of 8) are connected to the bus, each
unit can be controlled independently.
QM range App Note, document number 260283, rev 15
Command Code Transaction Type(s)
01h
02h
03h
19h
78h
81h
8Dh
90h
91h
98h
99h
9Ah
9Dh
9Eh
C4h
C5h
C6h
Read/Write Byte
Read/Write Byte
Send Byte
Read Byte
Read/Write Byte
Read/Write Byte
Read Word
Read Word
Read Word
Read Byte
Read Block
Read Block
Read Block
ASCII string – 10 characters
Read Block
Read Block
Read Block
Read Word
Notes
General unit status
Fan faults or warnings
LINEAR11 format
LINEAR11 format
LINEAR11 format
ASCII string –
"TDK_LAMBDA"
ASCII String – "QM"
Special format
Special format
Special format
Special format
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