Rainbow Electronics MAX34440 - Manual (Page 14)

PMBus 6-Channel Power-Supply Manager
MAX34440
14
Table 1. PMBus Command Codes
Detailed Description
The MAX34440 is a highly integrated system monitor
based upon a 16-bit MAXQ
M microcontroller with facto-
ry-programmed functionality to monitor up to six power
supplies. The device provides power-supply closed-loop
control, and local/remote thermal-sensing facilities.
The power-supply manager monitors the power-supply
output voltage and constantly checks for user-pro-
grammable overvoltage and undervoltage thresholds. It
also can margin the power-supply output voltage up or
down by a user-programmable level. The margining is
performed in a closed-loop arrangement, whereby the
device automatically adjusts a pulse-width-modulated
(PWM) output and then measures the resultant output
voltage. The power-supply manager can also sequence
the supplies in any order at both power-up and power-
down. With the addition of an external current-sense
amplifier, the device can also monitor currents.
Thermal monitoring can be accomplished using up to
eight temperature sensors, including an on-chip ther-
mal sensor, four DS75LV digital thermometers, and a
MAX6695 dual remote/local thermal temperature sensor.
Communication with the DS75LV and MAX6695 tem-
perature sensors is conducted through a dedicated I
2 C/
SMBus interface.
The device provides ALERT and FAULT output signals.
Host communications are conducted through a PMBus-
compatible communications port. Address input con-
nections are also provided to allow up to four MAX34440
devices to reside on the system’s I/O bus.
MAXQ is a registered trademark of Maxim Integrated
Products, Inc.
CODE COMMAND NAME TYPE
PAGE
0–5
PAGE
6–13
PAGE
255
NO. OF
BYTES
FLASH
STORED
(NOTE 2)
DEFAULT
VALUE
(NOTE 2) (NOTE 1)
00h PAGE R/W Byte R/W R/W R/W 1 N 00h
01h OPERATION R/W Byte R/W — W 1 N 00h
02h ON_OFF_CONFIG R/W Byte R/W R/W R/W 1 Y 1Ah
03h CLEAR_FAULTS Send Byte W W W 0 N —
10h WRITE_PROTECT R/W Byte R/W R/W R/W 1 N 00h
11h STORE_DEFAULT_ALL Send Byte W W W 0 N —
12h RESTORE_DEFAULT_ALL Send Byte W W W 0 N —
19h CAPABILITY Read Byte R R R 1 N 00h/10h
20h VOUT_MODE Read Byte R R R 1 FIXED 40h
25h VOUT_MARGIN_HIGH R/W Word R/W — — 2 Y 0000h
26h VOUT_MARGIN_LOW R/W Word R/W — — 2 Y 0000h
2Ah VOUT_SCALE_MONITOR R/W Word R/W — — 2 Y 7FFFh
38h IOUT_CAL_GAIN R/W Word R/W — — 2 Y 0000h
40h VOUT_OV_FAULT_LIMIT R/W Word R/W — — 2 Y 7FFFh
42h VOUT_OV_WARN_LIMIT R/W Word R/W — — 2 Y 7FFFh
43h VOUT_UV_WARN_LIMIT R/W Word R/W — — 2 Y 0000h
44h VOUT_UV_FAULT_LIMIT R/W Word R/W — — 2 Y 0000h
46h IOUT_OC_WARN_LIMIT R/W Word R/W — — 2 Y 7FFFh
4Ah IOUT_OC_FAULT_LIMIT R/W Word R/W — — 2 Y 0000h
4Fh OT_FAULT_LIMIT R/W Word — R/W — 2 Y 7FFFh
51h OT_WARN_LIMIT R/W Word — R/W — 2 Y 7FFFh
5Eh POWER_GOOD_ON R/W Word R/W — — 2 Y 0000h
5Fh POWER_GOOD_OFF R/W Word R/W — — 2 Y 0000h