MAX6693
7-Channel Precision Temperature Monitor
with Beta Compensation
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Detailed Description
The MAX6693 is a precision multichannel temperature
monitor that features one local and six remote tempera-
ture-sensing channels with a programmable alert
threshold for each temperature channel and a program-
mable overtemperature threshold for channels 1, 4, 5,
and 6 (see Figure 1). Communication with the MAX6693
is achieved through the SMBus serial interface and a
dedicated alert pin. The alarm outputs, OVERT and
ALERT, assert if the software-programmed temperature
thresholds are exceeded. ALERT typically serves as an
interrupt, while OVERT can be connected to a fan, sys-
tem shutdown, or other thermal-management circuitry.
ADC Conversion Sequence
In the default conversion mode, the MAX6693 starts the
conversion sequence by measuring the temperature on
channel 1, followed by 2, 3, local channel, 4, 5, and 6.
The conversion result for each active channel is stored
in the corresponding temperature data register.
Low-Power Standby Mode
Enter software standby mode by setting the STOP bit to
1 in the configuration 1 register. Enter hardware standby
by pulling STBY low. Software standby mode disables
the ADC and reduces the supply current to approxi-
mately 3µA. Hardware standby mode halts the ADC
clock, but the supply current is approximately 350µA.
During either software or hardware standby, data is
retained in memory. During hardware standby, the
SMBus interface is inactive. During software standby, the
SMBus interface is active and listening for commands.
The timeout is enabled if a start condition is recognized
on SMBus. Activity on the SMBus causes the supply cur-
rent to increase. If a standby command is received while
a conversion is in progress, the conversion cycle is inter-
rupted, and the temperature registers are not updated.
The previous data is not changed and remains available.
PIN NAME FUNCTION
9 DXP5
Combined Current Source and A/D Positive Input for Channel 5 Remote Diode. Connect to the anode
of a remote-diode-connected temperature-sensing transistor. Leave unconnected or connect to V
CC
if no remote diode is used. Place a 100pF capacitor between DXP5 and DXN5 for noise filtering.
10 DXN5
Cathode Input for Channel 5 Remote Diode. Connect the cathode of the channel 5 remote-diode-
connected transistor to DXN5.
11 DXN6
Cathode Input for Channel 6 Remote Diode. Connect the cathode of the channel 6 remote-diode-
connected transistor to DXN6.
12 DXP6
Combined Current Source and A/D Positive Input for Channel 6 Remote Diode. Connect to the anode
of a remote-diode-connected temperature-sensing transistor. Leave unconnected or connect to V
CC
if no remote diode is used. Place a 100pF capacitor between DXP6 and DXN6 for noise filtering.
13 STBY
Acti ve- Low S tand b y Inp ut. D r i ve S TBY l og i c- l ow to p l ace the M AX 6693 i n stand b y m od e, or l og i c- hi g h
for op er ate m od e. Tem p er atur e and thr eshol d d ata ar e r etai ned i n stand b y m od e.
14 N.C. No Connection. Must be connected to ground.
15 OVERT
Overtemperature Active-Low, Open-Drain Output. OVERT asserts low when the temperature of
channels 1, 4, 5, and 6 exceeds the programmed threshold limit.
16 V
CC
Supply Voltage Input. Bypass to GND with a 0.1µF capacitor.
17 ALERT
SMBus Alert (Interrupt), Active-Low, Open-Drain Output. ALERT asserts low when the temperature of
any channel exceeds the programmed ALERT threshold.
18 SMBDATA SMBus Serial Data Input/Output. Connect to a pullup resistor.
19 SMBCLK SMBus Serial Clock Input. Connect to a pullup resistor.
20 GND Ground
Pin Description (continued)
