Multichannel Remote/Local
Temperature Sensors
MAX1668/MAX1805/MAX1989
†
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +5V,
STBY
= V
CC
, configuration byte = X0XXXX00,
T
A
= -55°C to +125°C,
unless otherwise noted.) (Note 6)
PARAMETER
SMBus INTERFACE
Logic Input High Voltage
Logic Input Low Voltage
Logic Output Low Sink Current
ALERT
Output High Leakage
Current
Logic Input Current
STBY,
SMBCLK, SMBDATA; V
CC
= 4.5V to 5.5V
STBY,
SMBCLK, SMBDATA; V
CC
= 4.5V to 5.5V
ALERT,
SMBDATA forced to 0.4V
ALERT
forced to 5.5V
Logic inputs forced to V
CC
or GND
-2
6
1
+2
2.4
0.8
V
V
mA
µA
µA
CONDITIONS
MIN
TYP
MAX
UNITS
Note 1:
Guaranteed by design, but not production tested.
Note 2:
Quantization error is not included in specifications for temperature accuracy. For example, if the MAX1668/MAX1805/
MAX1989 device temperature is exactly +66.7°C, the ADC may report +66°C, +67°C, or +68°C (due to the quantization
error plus the +0.5°C offset used for rounding up) and still be within the guaranteed ±1°C error limits for the +60°C to
+100°C temperature range. See Table 2.
Note 3:
A remote diode is any diode-connected transistor from Table 1. T
R
is the junction temperature of the remote diode. See the
Remote-Diode Selection
section for remote-diode forward-voltage requirements.
Note 4:
The SMBus logic block is a static design that works with clock frequencies down to DC. While slow operation is possible, it
violates the 10kHz minimum clock frequency and SMBus specifications, and can monopolize the bus.
Note 5:
Note that a transition must internally provide at least a hold time in order to bridge the undefined region (300ns max) of
SMBCLK’s falling edge t
HD:DAT.
Note 6:
Specifications from -55°C to +125°C are guaranteed by design, not production tested.
Typical Operating Characteristics
(Typical
Operating Circuit,
V
CC
= +5V,
STBY
= V
CC
, configuration byte = X0XXXX00, T
A
= +25°C, unless otherwise noted.)
TEMPERATURE ERROR
vs. PC BOARD RESISTANCE
MAX1668/1805 toc01
TEMPERATURE ERROR
vs. TEMPERATURE
MAX1668/1805 toc02
TEMPERATURE ERROR
vs. SUPPLY NOISE FREQUENCY
WITH V
CC
0.1µF CAPACITOR REMOVED
2200pF BETWEEN DXN_ AND DXP_
250mV
P-P
16
12
8
4
0
MAX1668/1805 toc03
20
4
3
TEMPERATURE ERROR (°C)
NPN (CMPT3904)
2
1
0
-1
INTERNAL
PNP (CMPT3906)
24
20
TEMPERATURE ERROR (°C)
TEMPERATURE ERROR (°C)
10
PATH = DXP_ TO GND
0
-10
PATH = DXP_ TO V
CC
(5V)
100mV
P-P
-20
1
10
LEAKAGE RESISTANCE (MΩ)
100
-2
-50 -30 -10
10
30
50
70
90
110
TEMPERATURE (°C)
0.1
1
10
100
FREQUENCY (MHz)
4
_______________________________________________________________________________________
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
