Table 1. MAX6576 Time-Select Pin
Configuration
Table 2. MAX6577 Time-Select Pin
Configuration
MAX6576/MAX6577
SOT Temperature Sensors with
Period/Frequency Output
4 _______________________________________________________________________________________
Pin Description
Detailed Description
The MAX6576/MAX6577 low-cost, low-current (140µA
typ) temperature sensors are ideal for interfacing with
microcontrollers (µCs) or microprocessors (µPs). The
MAX6576 converts ambient temperature into a 50% duty-
cycle square wave with a period proportional to absolute
temperature. The MAX6577 converts ambient tempera-
ture into a 50% duty-cycle square wave with a frequency
proportional to absolute temperature. Time-select pins
(TS1, TS0) permit the internal temperature-controlled
oscillator (TCO) to be scaled by four preset multipliers.
The MAX6576/MAX6577 feature a single-wire interface to
minimize the number of port pins necessary for interfac-
ing with a µP.
MAX6576 Characteristics
The MAX6576 temperature sensor converts tempera-
ture to period. The output of the device is a free-
running, 50% duty-cycle square wave with a period that
is proportional to the absolute temperature (°K) of the
device (Figure 1). The MAX6576 has a push/pull CMOS
output with sharp edges. The speed of the output
square wave can be selected by hard-wiring TS1 and
TS0 as shown in Table 1. One of four scaled output
periods can be selected using TS1 and TS0.
MAX6577 Characteristics
The MAX6577 temperature sensor converts tempera-
ture to frequency. The output of the device is a free-
running, 50% duty-cycle square wave with a frequency
that is proportional to the absolute temperature (°K) of
the device (Figure 2). The MAX6577 has a push/pull
CMOS output with sharp edges. The speed of the out-
put square wave can be selected by hard-wiring TS1
and TS0 as shown in Table 2. One of four scaled output
frequencies can be selected using TS1 and TS0.
GND
GND
V
DD
GND
V
DD
GND 10
40
160
V
DD
V
DD
640
TS1 TS0
SCALAR MULTIPLIER
(µs/°K)
Note: The temperature, in °C, may be calculated as follows:
GND
GND
V
DD
GND
V
DD
GND 4
1
1/4
TS1 TS0
SCALAR MULTIPLIER
(Hz/°K)
V
DD
V
DD
1/16
1
2
3
Positive Supply Voltage
Ground
No Connection. Connect pin to GND or leave open.
FUNCTION
4, 5
Time-Select Pins. TS1 and TS0 set the temperature scale factor by connecting TS1 and TS0 to
either V
DD
or GND. See Tables 1 and 2.
PIN
N.C.
GND
V
DD
NAME
TS1, TS0
Note: The temperature, in °C, may be calculated as follows:
