TC77. Thermal Sensor with SPI Interface. Features. Description. Typical Applications. Package Types. Block Diagram. Typical Application

M Thermal Sensor with SPI Interface T77 Features Digital Temperature Sensing in -Pin SOT-23A and 8-Pin SOI Packages Outputs Temperature as a 13- Digital Word SPI and MIROWIRE ompatible Interface Solid State Temperature Sensing ±1 (max.) accuracy from +2 to +6 ±2 (max.) accuracy from -4 to +8 ±3 (max.) accuracy from - to +12 2.7V to.v Operating Range Low Power - 2 µa (typ.) ontinuous onversion Mode -.1 µa (typ.) Shutdown Mode Typical Applications Thermal Protection for Hard Disk Drives and Other P Peripherals P ard Devices for Notebook omputers Low ost Thermostat ontrols Industrial ontrol Office Equipment ellular Phones Thermistor Replacement Block Diagram V DD Internal Diode Temperature Sensor T77 Description The T77 is a serially accessible digital temperature sensor particularly suited for low cost and small formfactor applications. Temperature data is converted from the internal thermal sensing element and made available at anytime as a 13-bit two s compliment digital word. ommunication with the T77 is accomplished via a SPI and MIROWIRE compatible interface. It has a 12-bit plus sign temperature resolution of.62 per Least Significant (LSb). The T77 offers a temperature accuracy of ±1. (max.) over the temperature range of +2 to +6. When operating, the T77 consumes only 2 µa (typ.). The T77 s onfiguration register can be used to activate the low power Shutdown mode, which has a current consumption of only.1 µa (typ.). Small size, low cost and ease of use make the T77 an ideal choice for implementing thermal management in a variety of systems. Package Types S V SS SK SOT-23-1 V DD T77 Typical Application V DD V DD SI/O.1µF SI/O SK N V SS 1 SOI T77 V DD S N N 13- Sigma Delta A/D onverter Temperature Register Manufacturer ID Register Serial Port Interface S SI/O SK T77 S SK SI/O PImicro MU AN SK SDI V SS onfiguration Register V SS 22 Microchip Technology Inc. DS292A-page 1

1. ELETRIAL HARATERISTIS 1.1 Absolute Maximum Ratings V DD...6.V All inputs and outputs w.r.t. V SS... -.3V to V DD +.3V Storage temperature...-6 to +1 Ambient temp. with power applied...- to +12 Junction Temperature... 1 ESD protection on all pins: Human Body Model (HBM)...>4 kv Machine Model (MM)...>2V Notice: Stresses above those listed under "Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. D HARATERISTIS PIN FUNTION TABLE SI/O SK V SS S N V DD Name Function Serial Data Pin Serial lock Ground hip Select (Active-Low) No onnection Power Supply Electrical Specifications: Unless otherwise noted, all parameters apply at V DD = 2.7V to.v and T A = - to +12. Parameters Sym Min Typ Max Units onditions Power Supply Operating Voltage Range V DD 2.7. V Note 1 Operating urrent I DD 2 4 µa ontinuous Temperature onversion Mode Power-On Reset Threshold V POR 1.2 1.6 2.2 V V DD falling or rising edge Standby Supply urrent I DD-.1 1. µa Shutdown Mode STANDBY Temperature to s onverter Resolution 13 s AD LSb =.62 /bit (Note 4) Temperature onversion Time t T 3 4 ms Temperature Accuracy (Note 1) T ERR -1. -2. -3. +1. +2. +3. +2 < T A < +6-4 < T A < +8 - < T A < +12 T77-3.3MXX: V DD = 3.3V T77-.MXX: V DD =.V Note 1: The T77-3.3MXX and T77-.MXX will operate from a supply voltage of 2.7V to.v. However, the temperature accuracy of the T77-3.3MXX and T77-.MXX is specified at the nominal operating voltages of 3.3V and.v, respectively. As V DD varies from the nominal operating value, the accuracy may be degraded (Refer to Figures 2-6 and 2-7). 2: All time measurements are measured with respect to the % point of the signal. 3: Load apacitance, L = 8 pf, is used for A timing measurements of output signals. 4: Resolution = Temperature Range/No. of s = (+2-26 ) / (2 13 ) Resolution = 12/8192 =.62 / DS292A-page 2 22 Microchip Technology Inc.

D HARATERISTIS (ONTINUED) Electrical Specifications: Unless otherwise noted, all parameters apply at V DD = 2.7V to.v and T A = - to +12. Parameters Sym Min Typ Max Units onditions Digital Input/Output High Level Input Voltage V IH.7 V DD V DD +.3 V Low Level Input Voltage V IL -.3.3 V DD V High Level Output Voltage V OH 2.4 V I OH = -4 µa Low Level Output Voltage V OL.4 V I OL = +2 ma Input urrent I IN(), -1. I IN(1) -1. +1. +1. µa V IN = GND V IN = V DD Input Hysteresis.3.8 V SI/O, SK Pin apacitance IN, OUT 2 pf Tri-state Output Leakage urrent I O_LEAK -1. +1. µa V O = GND V O = V DD Serial Port A Timing (Notes 2, 3) lock Frequency f LK D 7. MHz S Fall to First Rising SK Edge t S-SK 1 ns S Low to Data Out Delay t S-SI/O 7 ns SK Fall to Data Out Delay t DO 1 ns S High to Data Out Tri-state t DIS 2 ns SK High to Data In Hold Time t HD ns Data In Set-up Time t SU 3 ns Thermal Package Resistance Thermal Resistance, SOT23- θ JA 23 /W Thermal Resistance, 8L-SOI θ JA 163 /W Note 1: The T77-3.3MXX and T77-.MXX will operate from a supply voltage of 2.7V to.v. However, the temperature accuracy of the T77-3.3MXX and T77-.MXX is specified at the nominal operating voltages of 3.3V and.v, respectively. As V DD varies from the nominal operating value, the accuracy may be degraded (Refer to Figures 2-6 and 2-7). 2: All time measurements are measured with respect to the % point of the signal. 3: Load apacitance, L = 8 pf, is used for A timing measurements of output signals. 4: Resolution = Temperature Range/No. of s = (+2-26 ) / (2 13 ) Resolution = 12/8192 =.62 / 22 Microchip Technology Inc. DS292A-page 3

S Data Output Timing t S-SK 1/f LK SK t S-SI/O t DO t DIS SI/O HI-Z MSb LSb HI-Z SI/O Data Input Set-up and Hold Timing (Data is clocked on the rising edge of SK) S S SK SK SI/O t HD t SU HI-Z SI/O t HD t SU HI-Z FIGURE 1-1: Timing Diagrams. DS292A-page 4 22 Microchip Technology Inc.

2. TYPIAL PERFORMANE URVES 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. Note: Unless otherwise indicated, all parameters apply at V DD = 3.3V for the T77-3.3MXX and V DD =.V for the T77-.MXX, and T A = - to +12. The T77-3.3MXX and T77-.MXX will operate from a supply voltage of 2.7V to.v. However, the temperature accuracy of the T77-3.3MXX and T77-.MXX is specified at the nominal operating voltages of 3.3V and.v, respectively. Temperature Error ( ) 3. 2. 3 Upper Specification Limit 1. 2. 1 Mean Mean + 3 -. -1. -1 Mean - 3-2. -2-3. -3 Lower Specification Limit - -3-1 2 4 6 8 1 12 Reference Temperature ( ) Shutdown urrent (µa).3.2.1 T77-3.3MXX V DD = 3.3 V. - -2 3 6 9 12 Temperature ( ) T77-.MXX V DD =. V FIGURE 2-1: (T77-XXMXX). Accuracy vs. Temperature FIGURE 2-4: Temperature. Shutdown urrent vs. Supply urrent (µa) 2 24 T A = +2 23 22 T A = - 21 T A = +12 2 2.7 3.1 3. 3.9 4.3 4.7.1. Supply Voltage (V) Power-On Reset Voltage (V) 2. 2. 1. 1... - -2 3 6 9 12 Temperature ( ) FIGURE 2-2: Supply urrent vs. Supply Voltage (T77-XXMXX). FIGURE 2-: Power-On Reset Voltage vs. Temperature (T77-XXMXX). Supply urrent (µa) 4 3 3 2 2 1 1 T77-.MXX V DD =. V T77-3.3MXX V DD = 3.3 V - -2 3 6 9 12 Temperature hange ( ).4.3 T77-3.3MXX.2.1 T A = +8 T A = +2 -.1 -.2 T A = -2 -.3 -.4 3 3.1 3.2 3.3 3.4 3. 3.6 Temperature ( ) Supply Voltage (V) FIGURE 2-3: Temperature. Supply urrent vs. FIGURE 2-6: Temperature Accuracy vs. Supply Voltage (T77-3.3MXX). 22 Microchip Technology Inc. DS292A-page

Temperature hange ( ).4.3.2.1 -.1 -.2 -.3 T77-.MXX T A = +2 T A = +8 T A = -2 -.4 4. 4.6 4.7 4.8 4.9.1.2.3.4. Supply Voltage (V) FIGURE 2-7: Temperature Accuracy vs. Supply Voltage (T77-.MXX). Percentage of Occurances (%) 4 Sample Size = 18 T A = +2 4 3 3 2 2 1 1-1 -.7 -. -.2.2..7 1 Temperature Error ( ) FIGURE 2-1: Histogram of Temperature Accuracy at +2 Degrees (T77-XXMXX). Percentage of Occurances (%) 3 3 2 2 1 1 Sample Size = 18 T A = - -3-2. -2-1. -1 -.. 1 1. 2 2. 3 Temperature Error ( ) Percentage of Occurances (%) Sample Size = 18 4 T A = +6 4 3 3 2 2 1 1-1 -.7 -. -.2.2..7 1 Temperature Error ( ) FIGURE 2-8: Histogram of Temperature Accuracy at - Degrees (T77-XXMXX). FIGURE 2-11: Histogram of Temperature Accuracy at +6 Degrees (T77-XXMXX). Percentage of Occurances (%) 4 3 3 2 2 1 1 Sample Size = 18 T A = -4-2 -1. -1 -.. 1 1. 2 Temperature Error ( ) FIGURE 2-9: Histogram of Temperature Accuracy at -4 Degrees (T77-XXMXX). Percentage of Occurances (%) 9 Sample Size = 18 8 T A = +8 7 6 4 3 2 1-2 -1. -1 -.. 1 1. 2 Temperature Error ( ) FIGURE 2-12: Histogram of Temperature Accuracy at +8 Degrees (T77-XXMXX). DS292A-page 6 22 Microchip Technology Inc.

Percentage of Occurances (%) 6 4 3 2 1 Sample Size = 18 T A = +12-3 -2. -2-1. -1 -.. 1 1. 2 2. 3 Temperature Error ( ) FIGURE 2-13: Histogram of Temperature Accuracy at +12 Degrees (T77-XXMXX). 22 Microchip Technology Inc. DS292A-page 7

3. FUNTIONAL DESRIPTION The T77 consists of a band-gap type temperature sensor, a 12-bit plus sign (13-bit) Sigma-Delta Analogto-Digital onverter (AD), an internal conversion oscillator (~3 khz) and a serial input/output port. These devices feature a three-wire serial interface that is fully compatible with SPI and MIROWIRE specifications and, therefore, allows simple communications with common microcontrollers and processors. The Shutdown mode can be used to reduce supply current for power sensitive applications. A Manufacturer s ID register identifies the T77 as a Microchip Technology product. Output ode +111 111 +2 +.62 +1 11 + 1 Temp + Temp - 1+1111 1111 1111 +12 1+111 111 -.62-2 1+11 11 FIGURE 3-1: Temperature To Digital Transfer Function (Non-linear Scale). DS292A-page 8 22 Microchip Technology Inc.

3.1 Temperature Data Format A 13-bit two s complement digital word is used to represent the temperature. The Least Significant (LSb) is equal to.62. Note that the last two LSb bits ( and 1) are tri-stated and are represented as a logic 1 in the table. 2 is set to logic 1 after the completion of the first temperature conversion following a powerup or voltage reset event. TABLE 3-1: Temperature T77 OUTPUT Binary MSB / LSB An over-temperature condition can be determined by reading only the first few Most Significant s (MSb) of the temperature data. For example, the microprocessor could read only the first four bits of the Temperature register in order to determine that an over-temperature condition exists. 3.2 Power-Up And Power-Down Hex +12 11 111 1 111 3E 87h +2 11 1 111 B 87h +.62 1111 Fh 111 7h -.62 1111 1111 1111 1111 FF FFh -2 1111 11 1 111 F3 87h - 111 1 1 111 E4 87h The T77 is in the ontinuous Temperature onversion mode at power-up. The first valid temperature conversion will be available approximately 3 ms (refer to Temperature to s onverter section listed in the D characteristics table) after power-up. 2 of the Temperature register is set to a logic 1 after the completion of the first temperature conversion following a powerup or voltage reset event. 2 is set to logic during the time needed to complete the first temperature conversion. Thus, the status of bit 2 can be monitored to indicate the completion of the first temperature conversion. A supply voltage lower than 1.6V (typ.) is considered a power-down state for the T77. The device will reset itself and continue its normal ontinuous onversion mode of operation when the supply voltage rises above the nominal 1.6V. A minimal supply voltage of 2.7V is required in order to ensure proper operation of the device. 3.3 Serial Bus Interface The serial interface consists of the hip Select (S), Serial lock (SK) and Serial Data (SI/O) signals. The T77 meets the SPI and MIROWIRE bus specifications, with the serial interface designed to be compatible with the Microchip PImicro family of microcontrollers. The S input is used to select the T77 when multiple devices are connected to the serial clock and data lines. The S line is also used to synchronize the data, which is written to, or read from, the device when S is equal to a logic voltage. The SK input is disabled when S is a logic 1. The falling edge of the S line initiates communication, while the rising edge of S completes the communication. The SK input is provided by the external microcontroller and is used to synchronize the data on the SI/O line. The Temperature and Manufacturer ID registers are read only while the onfiguration register is a read/ write register. Figure 3-2 provides a timing diagram of a read operation of the Temperature register. ommunication with the T77 is initiated when the S goes to a logic. The Serial I/O signal (SI/O) then transmits the first bit of data. The microcontroller serial I/O bus master clocks the data in on the rising edge of SK. The falling edge of SK is then used to clock out the rest of the data. After 14 bits of data (thirteen temperature bits and 2) have been transmitted, the SI/O line is then tri-stated. Note that S can be taken to a logic 1 at any time during the data transmission if only a portion of the temperature data information is required. The T77 will complete the conversion, and the output shift register will be updated, if S goes to the inactive state while in the middle of a conversion. Figure 3-3 provides a timing diagram of a multi-byte communication operation consisting of a read of the Temperature Data register, followed by a write to the onfiguration register. The first 16 SK pulses are used to transmit the T77's temperature data to the microcontroller. The second group of 16 SK pulses are used to receive the microcontroller command to place the T77 either in Shutdown or ontinuous Temperature onversion mode. Note that the T77 is in the ontinuous Temperature onversion mode at powerup. The data written to the T77 s onfiguration register should be either all s or all 1 s, corresponding to either the ontinuous Temperature onversion or Shutdown mode, respectively. The T77 is in Shutdown mode when s to 7 are all equal to 1 s. The T77 will be in the ontinuous onversion mode if a in any bit location from to 7 is written to the onfiguration register. 22 Microchip Technology Inc. DS292A-page 9

S LK t S-SK 1 8 13 SI/O HI-Z T T T 12 11 1 T T T T T T T T T T 9 8 7 6 4 3 2 1 HI-Z FIGURE 3-2: Temperature Read Timing Diagram - (Reading only the first 13 s of the Temperature Register). S LK t S-SK 1 8 1 8 1 8 1 8 SI/O HI-Z T 12 T 11 1 T T 9 T T T T T T T T T BIT HI-Z 8 7 6 4 3 2 1 2 1 14 13 12 11 1 9 8 7 6 4 3 2 1 HI-Z TEMPERATURE REGISTER Notes: 1. 2 = during power-up for the first temperature conversion. 2. 2 =1 after the completion of the first temperature conversion following power-up or a reset event. 3. s 1 and are DON T ARES. ONFIGURATION REGISTER Notes: 1. XX = ontinuous onversion Mode 2. XXFF = Shutdown Mode FIGURE 3-3: Diagram. Temperature Read Followed By A Write To The onfiguration Register Timing. It is recommended that the user write all s or all 1 s to the onfiguration register. While the following codes can be transmitted to the T77, any other code may put the T77 into a test mode reserved by Microchip for calibration and production verification tests. hex 1 hex 3 hex 7 hex F hex 1F hex 3F hex 7F hex FF hex The following communication steps can be used to obtain the Manufacturer's ID and put the device into the ontinuous onversion mode. The Manufacturer s ID register is only accessible for a read operation, if the T77 is in Shutdown mode. 1. S goes low to initiate the communication cycle. 2. Read 16 bits of temperature data from the Temperature register. 3. Write 16 bits of data (i.e. XXFF hex) to the onfiguration register to enter Shutdown mode. 4. Read the 16 bits from the Manufacturer's ID register (1:8 = 4 hex) to verify that the sensor is a Microchip device.. Write 8 to 16 bits of data ( or hex) to enter ontinuous onversion Mode. 6. Return S high to terminate the communication cycle. The time between a complete temperature conversion and data transmission is approximately 3 msec. DS292A-page 1 22 Microchip Technology Inc.

4. INTERNAL REGISTER STRUTURE The T77 Internal register structure consists of three registers. The Temperature and Manufacturer s Identification registers are read only, while the onfiguration register is write only. TABLE 4-1: REGISTERS FOR T77 Name 1 14 13 12 11 1 9 8 7 6 4 3 2 1 Value at Powerup/Reset ONFIG 1 14 13 12 11 1 9 8 7 6 4 3 2 1 XXXX/XXXX / TEMP T12 T11 T1 T9 T8 T7 T6 T T4 T3 T2 T1 T * x x 1111/1111 /*XX M_ID 1 1 1 x x 11/1 /XX * 2 = during power-up; otherwise, bit 2 =1 4.1 onfiguration Register (ONFIG) The onfiguration register is write only. This register selects either Shutdown, ontinuous onversion or Test modes: 1: = XXXX/XXXX 1111/1111 (Shutdown mode) 1: = XXXX/XXXX / (ontinuous onversion mode) The T77 is in Shutdown mode when bits to 7 are all equal to 1 s. The T77 will be in the ontinuous onversion mode if a in any bit location from to 7 is written to the onfiguration register. The T77 is in the ontinuous onversion mode at power-up. It is recommended that the user write all s or all 1 s to the onfiguration register because other bit codes may put the T77 in a test mode used for calibration and production verification tests. Section 3.3 lists the onfiguration register bit codes that can be written to the T77 without having the device enter a production test mode. During Shutdown mode, the serial bus is still active. The current consumption of the T77 will be less than 1 µa during the time between serial communication. 4.2 Temperature Register (TEMP) The Temperature register is read only and holds the temperature conversion data. s and 1 are undefined and will be tri-state outputs during a read sequence. 2 is set to a logic 1 after completion of the first temperature conversion following a power-up or reset event. 2 is set to a logic during the time needed to complete the first temperature conversion. Therefore, the status of bit 2 can be monitored to indicate that the T77 has completed the first temperature conversion. s 1:3 contain the 13 bit two s complement data from the temperature conversion. 4.3 Manufacturer s ID Register (M_ID) The Manufacturer s Identification code is contained in this read only register. The Manufacturer ID register is only available for a read operation when the T77 is in Shutdown mode. The Manufacturer s ID code is contained in bits 1:8 and is equal to 4 hex to indicate a Microchip device. s 1: are undefined and will be tristate outputs during a read sequence, while bits 7:2 are set to. 22 Microchip Technology Inc. DS292A-page 11

. APPLIATION INFORMATION The T77 does not require any additional components in order to measure temperature. However, it is recommended that a decoupling capacitor of.1 µf to 1 µf be provided between the V DD and V SS (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 (I) power pins in order to provide effective noise protection to the T77. The T77 measures temperature by monitoring the voltage of a diode located on the I die. A low-impedance thermal path between the die and the printed circuit board (PB) is provided by the I pins of the T77. Therefore, the T77 effectively monitors the temperature of the PB board. The thermal path between the ambient air is not as efficient because the plastic I housing package functions as a thermal insulator. Thus, the ambient air temperature (assuming that a large temperature gradient exists between the air and PB) has only a small effect on the temperature measured by the T77. A potential for self-heating errors can exist if the T77 SPI communication lines are heavily loaded. Typically, the self-heating error is negligible because of the relatively small current consumption of the T77. A temperature accuracy error of approximately. will result from self-heating if the SPI communication pins sink/source the maximum current specified for the T77. Therefore, to maximize the temperature accuracy, the output loading of the SPI signals should be minimized. DS292A-page 12 22 Microchip Technology Inc.

6. PAKAGING INFORMATION 6.1 Package Marking Information -Lead SOT-23 Example: XXNN T77-3.3MTTR = N T77-.MTTR = P P7 8-Lead SOI (1 mil) Example: XXXXXXXX XXXXYYWW NNN T77-33 I/SN222 7 Legend: XX...X ustomer specific information* Y Year code (last digit of calendar year) YY Year code (last 2 digits of calendar year) WW Week code (week of January 1 is week 1 ) NNN Alphanumeric traceability code Note: In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line thus limiting the number of available characters for customer specific information. * Standard marking consists of Microchip part number, year code, week code, and traceability code. Please check with your Microchip Sales Office. 22 Microchip Technology Inc. DS292A-page 13

-Lead Plastic Small Outline Transistor (OT) (SOT23) E E1 p B p1 D n 1 α c A A2 β L φ A1 Units Dimension Limits Number of Pins n Pitch p Outside lead pitch (basic) p1 Overall Height A Molded Package Thickness A2 Standoff A1 Overall Width E Molded Package Width E1 Overall Length D Foot Length L Foot Angle φ Lead Thickness c Lead Width B Mold Draft Angle Top α Mold Draft Angle Bottom β * ontrolling Parameter Significant haracteristic MIN.3.3..12.9.11.14.4.14 INHES* NOM.38.7.46.43.3.11.64.116.18.6.17 MAX.7.1.6.118.69.122.22 1.8.2 1 1 MILLIMETERS MIN NOM.9 1.9.9 1.18.9 1.1..8 2.6 2.8 1. 1.63 2.8 2.9.3.4.9.1.3.43 Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed.1 (.24mm) per side. JEDE Equivalent: MO-178 Drawing No. 4-91 MAX 1.4 1.3.1 3. 1.7 3.1. 1.2. 1 1 DS292A-page 14 22 Microchip Technology Inc.

8-Lead Plastic Small Outline (SN) Narrow, 1 mil (SOI) E E1 p 2 D B n 1 4 h α c A A2 φ β L A1 Units INHES* MILLIMETERS Dimension Limits MIN NOM MAX MIN NOM MAX Number of Pins n 8 8 Pitch p. 1.27 Overall Height A.3.61.69 1.3 1. 1.7 Molded Package Thickness A2.2.6.61 1.32 1.42 1. Standoff A1.4.7.1.1.18.2 Overall Width E.228.237.244.79 6.2 6.2 Molded Package Width E1.146.14.17 3.71 3.91 3.99 Overall Length D.189.193.197 4.8 4.9. hamfer Distance h.1.1.2.2.38.1 Foot Length L.19.2.3.48.62.76 Foot Angle φ 4 8 4 8 Lead Thickness c.8.9.1.2.23.2 Lead Width B.13.17.2.33.42.1 Mold Draft Angle Top α 12 1 12 1 Mold Draft Angle Bottom β 12 1 12 1 * ontrolling Parameter Significant haracteristic Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed.1 (.24mm) per side. JEDE Equivalent: MS-12 Drawing No. 4-7 22 Microchip Technology Inc. DS292A-page 1

NOTES: DS292A-page 16 22 Microchip Technology Inc.

ON-LINE SUPPORT Microchip provides on-line support on the Microchip World Wide Web site. The web site is used by Microchip as a means to make files and information easily available to customers. To view the site, the user must have access to the Internet and a web browser, such as Netscape or Microsoft Internet Explorer. Files are also available for FTP download from our FTP site. onnecting to the Microchip Internet Web Site The Microchip web site is available at the following URL: www.microchip.com The file transfer site is available by using an FTP service to connect to: ftp://ftp.microchip.com The web site and file transfer site provide a variety of services. Users may download files for the latest Development Tools, Data Sheets, Application Notes, User's Guides, Articles and Sample Programs. A variety of Microchip specific business information is also available, including listings of Microchip sales offices, distributors and factory representatives. Other data available for consideration is: Latest Microchip Press Releases Technical Support Section with Frequently Asked Questions Design Tips Device Errata Job Postings Microchip onsultant Program Member Listing Links to other useful web sites related to Microchip Products onferences for products, Development Systems, technical information and more Listing of seminars and events SYSTEMS INFORMATION AND UPGRADE HOT LINE The Systems Information and Upgrade Line provides system users a listing of the latest versions of all of Microchip's development systems software products. Plus, this line provides information on how customers can receive the most current upgrade kits.the Hot Line Numbers are: 1-8-7-234 for U.S. and most of anada, and 1-48-792-732 for the rest of the world. 922 22 Microchip Technology Inc. DS292A-page 17

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 (48) 792-41. Please list the following information, and use this outline to provide us with your comments about this document. To: RE: Technical Publications Manager Reader Response Total Pages Sent From: Name ompany Address ity / State / ZIP / ountry Telephone: ( ) - Application (optional): Would you like a reply? Y N FAX: ( ) - Device: T77 Questions: Literature Number: DS292A 1. What are the best features of this document? 2. How does this document meet your hardware and software development needs? 3. Do you find the organization of this document easy to follow? If not, why? 4. What additions to the document do you think would enhance the structure and subject?. What deletions from the document could be made without affecting the overall usefulness? 6. Is there any incorrect or misleading information (what and where)? 7. How would you improve this document? DS292A-page 18 22 Microchip Technology Inc.

PRODUT IDENTIFIATION 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: T77: Thermal Sensor with SPI Interface Supply Voltage: 3.3 = V DD = Accuracy optimized for 3.3V. = V DD = Accuracy optimized for.v Temperature Range: M = - to +12 Package: TTR = Plastic Small Outline Transistor (SOT-23), -lead (Tape and Reel only) OA = Plastic SOI, (1 mil Body), 8-lead Examples: a) T77-3.3MOA: 3.3V Thermal Sensor in SOI package. b) T77-.MOA:.V Thermal Sensor in SOI package. c) T77-3.3MOATR: 3.3V Thermal Sensor in SOI package, Tape and Reel. d) T77-.MOATR:.V Thermal Sensor in SOI package, Tape and Reel. e) T77-3.3MTTR: 3.3V Thermal Sensor in SOT-23 package, Tape and Reel. f) T77-.MTTR:.V Thermal Sensor in SOT-23 package, Tape and Reel. Sales and Support Data Sheets Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following: 1. Your local Microchip sales office 2. The Microchip orporate Literature enter U.S. FAX: (48) 792-7277 3. The Microchip Worldwide Site (www.microchip.com) Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using. New ustomer Notification System Register on our web site (www.microchip.com/cn) to receive the most current information on our products. 22 Microchip Technology Inc. DS292A-page19

NOTES: DS292A-page 2 22 Microchip Technology Inc.

Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip s products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, under any intellectual property rights. Trademarks The Microchip name and logo, the Microchip logo, KEELOQ, MPLAB, PI, PImicro, PISTART and PRO MATE are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. FilterLab, microid, MXDEV, MXLAB, PIMASTER, SEEVAL and The Embedded ontrol Solutions ompany are registered trademarks of Microchip Technology Incorporated in the U.S.A. dspi, dspidem.net, EONOMONITOR, FanSense, FlexROM, fuzzylab, In-ircuit Serial Programming, ISP, IEPI, microport, Migratable Memory, MPASM, MPLIB, MPLINK, MPSIM, PI, PIDEM, PIDEM.net, rfpi, Select Mode and Total Endurance are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. Serialized Quick Turn Programming (SQTP) is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. 22, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. Printed on recycled paper. Microchip received QS-9 quality system certification for its worldwide headquarters, design and wafer fabrication facilities in handler and Tempe, Arizona in July 1999 and Mountain View, alifornia in March 22. The ompany s quality system processes and procedures are QS-9 compliant for its PImicro 8-bit MUs, KEELOQ code hopping devices, Serial EEPROMs, microperipherals, non-volatile memory and analog products. In addition, Microchip s quality system for the design and manufacture of development systems is ISO 91 certified. 22 Microchip Technology Inc. DS292A - page 21

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