1 tc1023 tc1024 preliminary information tc1023/1024-05 6/12/97 precision temperature-to-voltage converters with shutdown mode tc1023 tc1024 typical application output voltage part no. package at 25 c temp. range tc1023voa 8-pin soic 250mv C 20 c to +100 c TC1023VUA 8-pin msop 250mv C 20 c to +100 c tc1024voa 8-pin soic 750mv C 20 c to +125 c tc1024vua 8-pin msop 750mv C 20 c to +125 c pin configuration precision temperature-to-voltage converters with shutdown mode features n linearized temperature-to-voltage converters n direct centigrade output voltage scaling (tc1023) n shutdown/calibrate mode n multi-zone temperature sensing capability n wide temperature measurement range (tc1024) ........................... C 20 c to +125 c n excellent temperature converter linearity .. 0.8 c over temperature n high temperature converter accuracy ......... 2 c at 25 c guaranteed n small packages ......... 8-pin soic and 8-pin msop applications n power supply thermal shut-down n temperature-controlled fans n temperature measurement/instrumentation n temperature regulators n consumer electronics n lithium battery temperature monitor general description the tc1023/1024 temperature sensors furnish a lin- earized output voltage directly proportional to measured temperature. the tc1023 has a temperature measure- ment range of C 20 c to +100 c. its output voltage is directly calibrated in degrees centigrade (i.e., v out = 10mv/ c x temperature c). an external pull-down resis- tor to a negative voltage source is required for temperature measurement below 0 c. the tc1024 has a temperature measurement range of C 20 c to +125 c, and operates with a single supply. it has the same output voltage slope with temperature as the tc1023 (10mv/ c). the output voltage range is 100mv at C 20 c to 1,750mv at +125 c. both devices have a chip enable input that reduces supply current to 1 m a (typical) when pulled active high. in this state, the output defaults to a high resistance allowing an external reference voltage to be directly connected for a/d calibration. small size, low cost, flexibility and low power operation make the tc1023/1024 suitable for a wide range of gen- eral purpose temperature measurement applications. v out nc nc gnd 8 7 6 5 1 2 3 4 v cc nc nc ce v out nc nc gnd nc nc v cc ce 18 27 36 45 tc1023voa tc1024voa TC1023VUA tc1024vua tc1023 i/o line v cc = 2.2v to 12v v out v cc gnd ce microcontroller a/d converter 8-pin soic msop-8 ordering information telcom semiconductor reserves the right to make changes in the circuitry and specifications of its devices.
2 tc1023 tc1024 precision temperature-to-voltage converters with shutdown mode preliminary information tc1023/1024-05 6/12/97 electrical characteristics : t a = C 20 c to +125 c , v cc = 5v 5%, gnd = 0v, unless otherwise specified. symbol parameter test conditions min typ max unit v cc supply voltage (tc1023) 2.2 12 v (tc1024) 3.0 12 i s supply current ce = v il 40 60 m a (note 1) i ce shutdown current ce = v ih 1 5 m a (note 2) v ih ce input logic high level 2.0 v v il ce input logic low level 0.8 v i ce ce input leakage current ce = v ih or v il C1 +1 m a t rec recovery time from shutdown ce = step from v ih to v il 400 m sec (note 3) v out v out output voltage (tc1024) t a = C 20 c and +125 c 270 1780 mv v out output voltage (tc1023) t a = C 20 c and +100 c C 230 1030 circuit per figure 1: r1 = 240k w v ss = C 12v (note 1) i src v out output source current 1.0 ma accuracy at room temperature t a = +25 c C 2 +2 c (note 4) accuracy at minimum temperature tc1023: t a = C 20 c C 4 +4 c tc1024: t a = C 20 c (note 4) accuracy at maximum temperature tc1023: t a = +100 c C 3 +3 c tc1024: t a = +125 c (note 4) nonlinearity note 5 C 0.8 +0.8 c line regulation 80 m v/v a v average slope of output voltage 10 mv/ c v outmax maximum output voltage tc1023: 2.2v v cc 12v v cc C 1.2 v tc1024: 3.0v v cc 12v (note 1) * static-sensitive device. unused devices must be stored in conductive material. protect devices from static discharge and static fields. stresses above those listed under absolute maximum ratings may cause perma- nent damage to the device. these are stress ratings only and functional operation of the device at these or any other conditions above those indicated in the operational sections of the specifications is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. absolute maximum ratings * supply voltage ............................................................15v input voltage, any terminal .............. C 1.0 to (v cc +0.3v) operating temperature (tc1023) ......... C 20 c to +100 c operating temperature (tc1024) ......... C 20 c to +125 c storage temperature ............................ C 55 c to +150 c lead temperature (soldering, 10 sec) ................. +300 c notes: 1. v out outputs open circuited. 2. v out is 0v through approximately 100k w to ground when ce = v ih . 3. recovery time is the period required for v out to rise from 0v (shutdown state) to the voltage corresponding to the measured temperature driving a 100pf capacitive load. 4. accuracy = difference between calculated output voltage (10mv/ c x device case temperature at specified temperature and power supply) and measured output voltage expressed in c. 5. nonlinearity = deviation of output voltage versus temperature from the best-fit straight line over the device rated temperat ure range.
3 tc1023 tc1024 preliminary information tc1023/1024-05 6/12/97 precision temperature-to-voltage converters with shutdown mode detailed description a plot of output voltage versus temperature for both the tc1023 and tc1024 appears in figure 5. the tc1023 can be used with single power supply to measure temperatures from 0 c to 100 c. a pull-down resistor (r1 in figure 1) must be added from the output pin to the negative power supply for measuring temperatures less than 0 c. the value of the resistor must be chosen to limit the maximum current pulled from the output to the negative supply to C 50 m a (i.e., r1 = v ss /50 m a). figure 1. tc1023 connections output stage both devices have class a output stages capable of sourcing 1ma. these devices have a limited ability to drive heavy capacitive loads. loads of 50pf (to ground) can be driven directly. for heavier loads, a 2k w (or greater) resis- tor should be placed in series with the output for decoupling. if the tc1023/1024 is used in a noisy electrical environ- ment, a 0.1 m f bypass capacitor from v cc to gnd is recom- mended. shutdown/calibrate mode the tc1023/1024 enters shutdown when the ce input is taken to v ih . this causes quiescent current to fall to 1 m a (typ) and the output to drop immediately to 0v through approximately 100k w . for applications where the tc1023/ 1024 is connected to an external a/d converter, a refer- ence voltage can be directly connected to v out while in shutdown for a/d calibration, as shown in figure 3. a cmos gate provides bias voltage to the bandgap refer- ence v r , and at the same time disables the tc102x by taking ce to v ih . limiting resistor r1 should be chosen to limit current through the voltage reference to the desired current (i ref ). that is, r1 = (v oh C v ref )/i ref (where v oh is the cmos gate output high voltage at output current equal to i ref ; and v ref is the reference voltage of v r ). figure 2. tc1024 connections figure 3. a/d calibration multi-zone temperature sensing the ce input facilitates multi-zone temperature sens- ing as shown in the example of figure 4. in this example, the processor addresses either of two sensors with a single i/o port pin. the tc102x v out pins are connected together and routed to the processor's a/d converter, eliminating the need for separate a/d input channels for each sensor. figure 4. tc1023/1024 addressing tc1023 gnd ce v cc = 2.2v to 12.0v min. v cc v out v ss r1 = v ss /50 a v out tc102x gnd ce v cc v cc v out tc102x gnd zone 1/zone 2 zone 1 zone 2 ce v cc v out i/o pin microcontroller a/d converter tc102x gnd r1 ce v cc v cc cal a/d converter cmos gate 2.5v ref v out tc1024 gnd tc1024 (?20 c to +125 c) v cc = 3.0v to 12.0v v cc v out ce v out
4 tc1023 tc1024 precision temperature-to-voltage converters with shutdown mode preliminary information tc1023/1024-05 6/12/97 figure 5. output voltage vs. temperature 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 ?0.1 ?0.2 ?40 v out (volts) temperature ( c) ?30 ?20 ?0 0 10 20 30 40 50 60 70 80 90 100 110 120 130 tc1024 tc1023 tc1023: v out = (10mv/ c) (temperature c) tc1024: v out = (10mv/ c) (temperature c) + 500mv
5 tc1023 tc1024 preliminary information tc1023/1024-05 6/12/97 precision temperature-to-voltage converters with shutdown mode dimensions: inches (mm) .122 (3.10) .114 (2.90) .122 (3.10) .114 (2.90) .043 (1.10) max. .006 (0.15) .002 (0.05) .016 (0.40) .010 (0.25) .197 (5.00) .187 (4.80) pin 1 .008 (0.20) .005 (0.13) .028 (0.70) .016 (0.40) 6 max. .026 (0.65) typ. 8-pin msop package dimensions 8-pin soic .050 (1.27) typ. 8 max. pin 1 .244 (6.20) .228 (5.79) .157 (3.99) .150 (3.81) .197 (5.00) .189 (4.80) .018 (0.46) .014 (0.36) .010 (0.25) .004 (0.10) .069 (1.75) .053 (1.35) .010 (0.25) .007 (0.18) .050 (1.27) .016 (0.40)
6 tc1023 tc1024 precision temperature-to-voltage converters with shutdown mode preliminary information tc1023/1024-05 6/12/97 sales offices telcom semiconductor 1300 terra bella avenue p.o. box 7267 mountain view, ca 94039-7267 tel: 415-968-9241 fax: 415-967-1590 e-mail: liter@c2smtp.telcom-semi.com printed in the u.s.a. telcom semiconductor austin product center 9101 burnet rd. suite 214 austin, tx 78758 tel: 512-873-7100 fax: 512-873-8236 telcom semiconductor h.k. ltd. 10 sam chuk street, ground floor san po kong, kowloon hong kong tel: 852-2324-0122 fax: 852-2354-9957
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