Rainbow Electronics MAX6667 - Manual

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 temper-
ature information contained in the duty cycle of the out-
put 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 t 1 ) / t 2
Where t 1 is fixed with a typical value of 10ms and t 2 is
modulated by the temperature (Figure 1). The
MAX6666/MAX6667 operate from -40°C to +125°C and
are available in space-saving SOT23* and µMAX pack-
ages.
Applications
Process Control
Industrial
HVAC and Environmental Control
Automotive
µP and µC Temperature Monitoring
Features
♦ Simple Single-Wire PWM Output
♦ ±1.0°C Accuracy at +25°C
♦ High Accuracy
±1°C at T
A
= +30°C
±2.5°C at T A = +10°C to +50°C
♦ Operate Up to +125°C
♦ Low 200µA Typical Current Consumption
♦ Multiple Package Options
6-Pin SOT23*
8-Pin SO
8-Pin µMAX
MAX6666/MAX6667
High-Accuracy PWM Output Temperature
Sensors
________________________________________________________________ Maxim Integrated Products 1
IC
IC IC
1
2
8
7
IC
IC V CC
GND
D OUT
µMAX/SO
TOP VIEW
3
4
6
5
MAX6666
MAX6667
Pin Configurations
Ordering Information
V CC
+3.3V
GND
DOUT
t 1
t 2
µC
INPUT TO
TIMER/COUNTER
MAX6666
MAX6667
Typical Operating Circuit
19-2138; Rev 0; 7/01
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Pin Configurations continued at end of data sheet.
PART TEMP. RANGE PIN-PACKAGE
MAX6666AUT-T* -40°C to +125°C 6 SOT23-6
MAX6666AUA -40°C to +125°C 8 µMAX
MAX6666ASA -40°C to +125°C 8 SO
MAX6667AUT-T* -40°C to +125°C 6 SOT23-6
MAX6667AUA -40°C to +125°C 8 µMAX
MAX6667ASA -40°C to +125°C 8 SO
*Future product—contact factory for availability.