TC74_13 Datasheet, PDF (1/18 Pages) Microchip Technology – Tiny Serial Digital Thermal Sensor

TC74
Tiny Serial Digital Thermal Sensor
Features
• Digital Temperature Sensing in SOT-23-5 or
TO-220 Packages
• Outputs Temperature as an 8-Bit Digital Word
• Simple SMBus/I²C™ Serial Port Interface
• Solid-State Temperature Sensing:
- ±2°C (max.) Accuracy from +25°C to +85°C
- ±3°C (max.) Accuracy from 0°C to +125°C
• Supply Voltage of 2.7V to 5.5V
• Low Power:
- 200 µA (typ.) Operating Current
- 5 µA (typ.) Standby Mode Current
Applications
• Thermal Protection for Hard Disk Drives
and other PC Peripherals
• PC Card Devices for Notebook Computers
• Low Cost Thermostat Controls
• Power Supplies
• Thermistor Replacement
Package Types
TO-220
TC74
12345
SOT-23
SDA
SCLK
5
4
TC74
1
2
3
NC GND V_DD
Note: The TO-220 tab is connected
to pin 3 (GND)
General Description
The TC74 is a serially accessible, digital temperature
sensor particularly suited for low cost and small form-
factor applications. Temperature data is converted from
the onboard thermal sensing element and made
available as an 8-bit digital word.
Communication with the TC74 is accomplished via a 2-
wire SMBus/I²C compatible serial port. This bus also
can be used to implement multi-drop/multi-zone
monitoring. The SHDN bit in the CONFIG register can
be used to activate the low power Standby mode.
Temperature resolution is 1°C. Conversion rate is a
nominal 8 samples/sec. During normal operation, the
quiescent current is 200 µA (typ). During standby
operation, the quiescent current is 5 µA (typ).
Small size, low installed cost and ease of use make the
TC74 an ideal choice for implementing thermal
management in a variety of systems.
Functional Block Diagram
Internal Sensor
(Diode)
 Modulator
Serial Port
Interface
Control
Logic
SDA
SCLK
Temperature
Register
 2001-2012 Microchip Technology Inc.
DS21462D-page 1