QM range App Note, document number 260283, rev 15
Page 41 of 48
14.
PMBus™
Overview of the PMBus™ Interface
Standard 100kHz operation
PEC (Packet Error Checking) supported
Monitoring of status - reading and clearing of fault and warning indications
Reading manufacturing related data
– manufacturer id, model name, serial number & manufacturing date
Reading of fan speeds and inlet temperature
Reading operating time and power cycle count
On/Off control of the module outputs by PMBus™ Command, PMBus™ Control Pin, or a combination of both
Up to 8 units may be connected to a single PMBus™ controller
Hardware Interface
1
2
PMBus™ Options Board Connector
3
4
5
6
7
8
9
10
11
12
Standby V Out +
N/C
PMBus™ Address 0
SCL - Clock
SDA - Data
GND
Standby V Out -
Fan Fail Out
PMBus™ Address 3
PMBus™ Address 1
PMBus™ Address 2
PMBus™ Control Line In
12-Way Molex
Pin #
Use
Notes
J5-1
Standby V Out +
Standby Voltage Supply Output (+ve)
J5-2
Standby V Out -
Standby Voltage Supply Output (-ve)
J5-3
N/C
Not Connected
J5-4
Fan Fail Out
Open Collector, see below
J5-5
PMBus Address 0
These lines are pulled high internally. Pull to Ground (pin 12) to
select different PMBus addresses. See Section 3 below.
J5-6
PMBus Address 1
J5-7
PMBus Address 2
J5-8
PMBus Address 3
J5-9
SCL
– Clock
Logic 0/1
– GND/3v3
J5-10
SDA - Data
Logic 0/1
– GND/3v3
J5-11
PMBus Control Line In
Logic 0/1
– GND/3v3
J5-12
GND
Reference Ground for J5-4 to J5-11
