MAX6657MSA Maxim Integrated Products, MAX6657MSA Datasheet - Page 6

• Manufacturer Part Number: MAX6657MSA
• Description: Board Mount Temperature Sensors
• Manufacturer: Maxim Integrated Products

Specifications of MAX6657MSA

• Full Temp Accuracy: +/- 5 C
• Package / Case: SOIC-8 Narrow
• Digital Output - Bus Interface: Serial (2-Wire, I2C)
• Digital Output - Number Of Bits: 10 bit + Sign
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: 0 C
• Output Type: Digital
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

±1°C, SMBus-Compatible Remote/Local Temperature
Sensors with Overtemperature Alarms
The MAX6657/MAX6658/MAX6659 are temperature
sensors designed to work in conjunction with a micro-
processor or other intelligence in thermostatic,
process-control, or monitoring applications. Com-
munication with the MAX6657/MAX6658/MAX6659
occurs through the SMBus serial interface and dedicat-
ed alert pins. Two independent overtemperature alarms
(OVERT1 and OVERT2) are asserted if their software
programmed temperature thresholds are exceeded.
OVERT1 and OVERT2 can be connected to fans, a sys-
tem shutdown, or other thermal management circuitry.
The MAX6657/MAX6658/MAX6659 convert tempera-
tures to digital data either at a programmed rate or a
single conversion. Conversions have a 0.125°C resolu-
tion (extended resolution) or 1°C resolution (legacy res-
olution). Extended resolution represents temperature as
6
_______________________________________________________________________________________
DXP
DXN
(OVERT2)
OVERT1
ALERT
V
CC
Detailed Description
Q
Q
Q
R
R
R
S
S
S
DIODE
FAULT
REMOTE
LOCAL
MUX
MAX6659 ONLY
REMOTE TEMPERATURE
(OVERT2 THRESHOLD)
LOCAL TEMPERATURE
REGISTER BANK
OVERT1 THRESHOLD
ALERT THRESHOLD
ALERT RESPONSE
COMMAND BYTE
ADDRESS
10 bits + sign bit and is available for autonomous con-
versions that are 4Hz and slower and single-shot con-
versions. Legacy resolution represents temperature as
7 bits + sign bit and allows for faster autonomous con-
version rates of 8Hz and 16Hz.
The averaging ADC integrates over a 60ms period
(each channel, typically, in the 7-bit + sign legacy
mode). Using an averaging ADC attains excellent noise
rejection.
The multiplexer automatically steers bias currents
through the remote and local diodes. The ADC and
associated circuitry measure each diode’s forward volt-
age and compute the temperature based on this volt-
age. If the remote channel is not used, connect DXP to
DXN. Do not leave DXP and DXN unconnected. When a
conversion is initiated, both channels are converted
ADC
8
8
( ) ARE FOR MAX6659 ONLY
7
READ
WRITE
CONTROL
DECODER
ADDRESS
SMBus
LOGIC
Functional Diagram
2
MAX6657
MAX6658
MAX6659
ADC and Multiplexer
(STBY)
SMBDATA
SMBCLK
(ADD)