MAX6666/MAX6667
High-Accuracy PWM Output Temperature Sensors
General Description
The MAX6666/MAX6667 are high-accuracy, low-cost,
low-power temperature sensors with a single-wire
output. The MAX6666/MAX6667 convert the ambient
temperature into a ratiometric PWM output with tempera-
ture information contained in the duty cycle of the output
square wave. The MAX6666 has a push-pull output and
the MAX6667 has an open-drain output.
The MAX6666/MAX6667 operate at supply voltages from
+3V to +5.5V. The typical unloaded supply current at 5.0V
is 200µA. Both devices feature a single-wire output that
minimizes the number of pins necessary to interface with
a microprocessor (µP). The output is a square wave with
a nominal frequency of 35Hz (±20%) at +25°C. The output
format is decoded as follows:
Temperature (°C) = 235 - (400 x t1)/t2
Where t1 is fixed with a typical value of 10ms and t2 is
modulated by the temperature (Figure 1). The MAX6666/
MAX6667 operate from -40°C to +125°C and are avail-
able in space-saving SOT23 packages.
Applications
●● Process Control
●● Industrial
●● HVAC and Environmental Control
●● µP and µC Temperature Monitoring
Features
●● Simple Single-Wire PWM Output
●● ±1.0°C Accuracy at +25°C
●● High Accuracy
±1°C at TA = +30°C
±2.5°C at TA = +10°C to +50°C
●● Operate Up to +125°C
●● Low 200µA Typical Current Consumption
●● Small SOT23 package
Ordering Information
PART
TEMP RANGE
PIN-
PACKAGE
TOP
MARK
MAX6666AUT+T -40°C to +125°C 6 SOT23
AATF
MAX6667AUT+T -40°C to +125°C 6 SOT23
AATG
+Denotes a lead(Pb)-free/RoHS-compliant package.
T = Tape and reel.
Typical Operating Circuit
+3.3V
VCC
MAX6666
MAX6667
DOUT
GND
t1
t2
µC
INPUT TO
TIMER/COUNTER
Pin Configuration
TOP VIEW
+
DOUT 1
VCC 2
MAX6666
MAX6667
6 I.C.
5 I.C.
GND 3
4 I.C.
SOT23
19-2138; Rev 4; 4/14
