Datasheet

ManualsBrandsMICROCHIP TECHNOLOGY ManualsPMICsTC77-5.0MCTTR

 2002-2012 Microchip Technology Inc. DS20092B-page 1

TC77

Features

• Digital Temperature Sensing in 5-Pin SOT-23A

and 8-Pin SOIC Packages

• Outputs Temperature as a 13-Bit Digital Word

• SPI and MICROWIRE™ Compatible Interface

• Solid State Temperature Sensing

• ±1°C (max.) accuracy from +25°C to +65°C

• ±2°C (max.) accuracy from -40°C to +85°C

• ±3°C (max.) accuracy from -55°C to +125°C

• 2.7V to 5.5V Operating Range

•Low Power

- 250 µA (typ.) Continuous Conversion Mode

- 0.1 µA (typ.) Shutdown Mode

Typical Applications

• Thermal Protection for Hard Disk Drives and

Other PC Peripherals

• PC Card Devices for Notebook Computers

• Low Cost Thermostat Controls

• Industrial Control

• Office Equipment

• Cellular Phones

• Thermistor Replacement

Block Diagram

Description

The TC77 is a serially accessible digital temperature

sensor particularly suited for low cost and small form-

factor applications. Temperature data is converted from

the internal thermal sensing element and made avail-

able at anytime as a 13-bit two’s compliment digital

word. Communication with the TC77 is accomplished

via a SPI and MICROWIRE compatible interface. It has

a 12-bit plus sign temperature resolution of 0.0625°C

per Least Significant Bit (LSb). The TC77 offers a tem-

perature accuracy of ±1.0°C (max.) over the tempera-

ture range of +25°C to +65°C. When operating, the

TC77 consumes only 250 µA (typ.). The TC77’s Con-

figuration register can be used to activate the low

power Shutdown mode, which has a current consump-

tion of only 0.1 µA (typ.). Small size, low cost and ease

of use make the TC77 an ideal choice for implementing

thermal management in a variety of systems.

Package Types

Typical Application

TC77

Diode

Temperature

Sensor

SCK

Serial

Port

Interface

SI/O

13-Bit

Sigma Delta

A/D Converter

Temperature

Internal

Configuration

Manufacturer

ID Register

SOT-23-5

SOIC

SCK

SI/O

TC77

SCK

SI/O

AN0

SCK

SDI

SCK

SI/O

TC77

0.1µF

PIC

MCU

Thermal Sensor with SPI Interface

Summary of content (22 pages)

PAGE 1
TC77 Thermal Sensor with SPI Interface Features Description • Digital Temperature Sensing in 5-Pin SOT-23A and 8-Pin SOIC Packages • Outputs Temperature as a 13-Bit Digital Word • SPI and MICROWIRE™ Compatible Interface • Solid State Temperature Sensing • ±1°C (max.) accuracy from +25°C to +65°C • ±2°C (max.) accuracy from -40°C to +85°C • ±3°C (max.) accuracy from -55°C to +125°C • 2.7V to 5.5V Operating Range • Low Power - 250 µA (typ.) Continuous Conversion Mode - 0.1 µA (typ.
PAGE 2
TC77 1.0 1.1 ELECTRICAL CHARACTERISTICS PIN FUNCTION TABLE Name Absolute Maximum Ratings † Function SI/O Serial Data Pin VDD ........................................................................6.0V SCK Serial Clock All inputs and outputs w.r.t. VSS ..... -0.3V to VDD +0.3V VSS Ground CS Chip Select (Active-Low) NC No Connection VDD Power Supply Storage temperature ..........................-65°C to +150°C Ambient temp. with power applied .....-55°C to +125°C Junction Temperature......
PAGE 3
TC77 DC CHARACTERISTICS (CONTINUED) Electrical Specifications: Unless otherwise noted, all parameters apply at VDD = 2.7V to 5.5V and TA = -55°C to +125°C. Parameters Sym Min Typ Max Units Conditions High Level Input Voltage VIH 0.7 VDD — VDD + 0.3 V Low Level Input Voltage VIL -0.3 — 0.3 VDD V High Level Output Voltage VOH 2.4 — — V IOH = -400 µA Low Level Output Voltage VOL — — 0.4 V IOL = +2 mA Input Current IIN(0), IIN(1) -1.0 -1.0 — — +1.0 +1.
PAGE 4
TC77 Data Output Timing CS tCS-SCK 1/fCLK SCK tCS-SI/O SI/O HI-Z tDO tDIS LSb MSb HI-Z SI/O Data Input Set-up and Hold Timing (Data is clocked on the rising edge of SCK) CS CS SCK SCK tHD tHD tSU HI-Z SI/O FIGURE 1-1: DS20092B-page 4 SI/O tSU HI-Z Timing Diagrams.  2002-2012 Microchip Technology Inc.
PAGE 5
TC77 2.0 TYPICAL PERFORMANCE CURVES Note: The graphs and tables provided following this note are a statistical summary based on a limited number of samples and are provided for informational purposes only. The performance characteristics listed herein are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified operating range (e.g., outside specified power supply range) and therefore outside the warranted range. 3.5 3 2.5 2 1.5 1 0.5 0 -0.5 -1 -1.5 -2 -2.
PAGE 6
TC77 Percentage of Occurances (%) Temperature Change (°C) 0.4 TC77-5.0MXX 0.3 0.2 TA = +25°C 0.1 0 TA = +85°C -0.1 TA = -25°C -0.2 -0.3 -0.4 4.5 4.6 4.7 4.8 4.9 5 50 Sample Size = 108 TA = +25°C 45 40 35 30 25 20 15 10 5 0 -1 5.1 5.2 5.3 5.4 5.5 -0.75 -0.5 Supply Voltage (V) 35 Sample Size = 108 TA = -55°C 25 20 15 10 5 0 0.25 0.5 0.75 1 50 Sample Size = 108 TA = +65°C 45 40 35 30 25 20 15 10 5 0 -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3 -1 -0.75 -0.
PAGE 7
Percentage of Occurances (%) TC77 60 50 Sample Size = 108 TA = +125°C 40 30 20 10 0 -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5 3 Temperature Error (°C) FIGURE 2-13: Histogram of Temperature Accuracy at +125 Degrees C (TC77-XXMXX).  2002-2012 Microchip Technology Inc.
PAGE 8
TC77 3.0 FUNCTIONAL DESCRIPTION The TC77 consists of a band-gap type temperature sensor, a 12-bit plus sign (13-bit) Sigma-Delta Analogto-Digital Converter (ADC), an internal conversion oscillator (~30 kHz) and a serial input/output port. These devices feature a three-wire serial interface that is fully compatible with SPI and MICROWIRE specifications and, therefore, allows simple communications with common microcontrollers and processors.
PAGE 9
TC77 3.1 Temperature Data Format 3.3 A 13-bit two’s complement digital word is used to represent the temperature. The Least Significant Bit (LSb) is equal to 0.0625°C. Note that the last two LSb bits (Bit 0 and 1) are tri-stated and are represented as a logic ‘1’ in the table. Bit 2 is set to logic ‘1’ after the completion of the first temperature conversion following a powerup or voltage reset event.
PAGE 10
TC77 CS tCS-SCK CLK 1 SI/O HI-Z 8 T 11 T 12 T 9 T 10 T 8 T 7 T 6 13 T 5 T 4 T 3 T 2 T 1 HI-Z T 0 FIGURE 3-2: Temperature Read Timing Diagram - (Reading only the first 13 Bits of the Temperature Register). CS tCS-SCK CLK 1 SI/O HI-Z T T T 12 11 10 8 T 9 T 8 T 7 T 6 T 5 1 T 4 8 T 3 T 2 T 1 T BIT 0 2 HI-Z 1 1 8 C C C C C C 15 14 13 12 11 10 C 9 C 8 C 7 TEMPERATURE REGISTER Notes: CONFIGURATION REGISTER Notes: 1. 1. 2. 2. 3.
PAGE 11
TC77 4.0 INTERNAL REGISTER STRUCTURE The TC77 Internal register structure consists of three registers. The Temperature and Manufacturer’s Identification registers are read only, while the Configuration register is write only.
PAGE 12
TC77 5.0 APPLICATION INFORMATION The TC77 does not require any additional components in order to measure temperature. However, it is recommended that a decoupling capacitor of 0.1 µF to 1 µF be provided between the VDD and VSS (Ground) pins (a high frequency ceramic capacitor should be used). It is necessary for the capacitor to be located as close as possible to the integrated circuit (IC) power pins in order to provide effective noise protection to the TC77.
PAGE 13
TC77 6.0 PACKAGING INFORMATION 6.1 Package Marking Information Example: 5-Lead SOT-23 TC77-3.3MCTTR = CN XXNN TC77-5.0MCTTR = CP 8-Lead SOIC (150 mil) XXXXXXXX XXXXYYWW NNN Legend: Note: * XX...
PAGE 14
TC77 5-Lead Plastic Small Outline Transistor (OT) (SOT23) Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.
PAGE 15
TC77 8-Lead Plastic Small Outline (SN) – Narrow, 150 mil (SOIC) Note: For the most current package drawings, please see the Microchip Packaging Specification located at http://www.microchip.
PAGE 16
TC77 NOTES: DS20092B-page 16  2002-2012 Microchip Technology Inc.
PAGE 17
TC77 THE MICROCHIP WEB SITE CUSTOMER SUPPORT Microchip provides online support via our WWW site at www.microchip.com. This web site is used as a means to make files and information easily available to customers.
PAGE 18
TC77 READER RESPONSE It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation can better serve you, please FAX your comments to the Technical Publications Manager at (480) 792-4150. Please list the following information, and use this outline to provide us with your comments about this document.
PAGE 19
TC77 PRODUCT IDENTIFICATION SYSTEM To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office. PART NO. -X.X X XX Device Supply Voltage Temperature Range Package Device: TC77: Thermal Sensor with SPI Interface Supply Voltage: 3.3 = VDD = Accuracy optimized for 3.3V 5.0 = VDD = Accuracy optimized for 5.
PAGE 20
TC77 NOTES: DS20092B-page 20  2002-2012 Microchip Technology Inc.
PAGE 21
Note the following details of the code protection feature on Microchip devices: • Microchip products meet the specification contained in their particular Microchip Data Sheet. • Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the intended manner and under normal conditions. • There are dishonest and possibly illegal methods used to breach the code protection feature.
PAGE 22
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