1 ltk001 001fa , ltc and lt are registered trademarks of linear technology corporation. all other trademarks are the property of their respective owners. for typical performance curves and applications circuits consult the lt1025 data sheet. 0.75 c initial accuracy (a version) extremely low warmup drift preset outputs for type e, j, k, r, s, t single 5v to 20v operation 480 a typical supply current available in 8-pin dip package thermocouple cold junction compensation thermocouple cold junction compensator and matched amplifier type k 10mv/ c thermometer the ltk001 is a thermocouple amplifier supplied with amatched cold junction compensator. by separating the amplifier and compensator functions, the problem of compensator temperature rise is virtually eliminated. the compensator is a selected version of the lt 1025 cold junction compensator. the amplifier, which is also avail-able separately as ltka0x has been specially selected for thermocouple applications. it has low supply current to minimize warmup drift, very low offset voltage (<35 v), high gain, and extremely low input bias currents (<600pa) to allow high impedance input filters to be used without degrading offset voltage or drift. matching of the kits is accomplished by separating the compensators and amplifiers according to the polarity of their initial (room temperature) errors. this eliminates the need to sum the errors of the two components to find the worst-case error. the ltk001 has direct thermocouple outputs of 60.9 v/ c (e), 51.7 v/ c (j), 40.6 v/ c (k, t), and 5.95 v/ c (r, s). it also has a 10mv/ c output which can be scaled to match any arbitrary thermocouple.for multiple thermocouple applications using one com- pensator, amplifiers may be ordered separately (ltka0x), still matched to the compensator. features descriptio u applicatio s u + v + v v + v ltka0x r4* type k gnd r k v 0 v out 10mv/ c v in lt1025 c1 0.1 f c20.1 f r1 1k 1% r3** 255k 1% r2 100 ? full-scale trim + * v * r4 30 a , r4 is not required (open) for lt1025 temperatures 0 c. **selected for 0 c?00 c range ltk001 ta01 typical applicatio u downloaded from: http:///
2 ltk001 001fa amplifier (ltka0x)supply voltage (total v + to v ) ............................... 40v differential input current (note 2) ...................... 10ma common mode input voltage ............. equal to supplies output short-circuit duration .......................... indefinite compensator (lt1025) supply voltage (v in to ground pin) ......................... 36v output voltage (forced) ............................................ 5v output short-circuit duration .......................... indefinite package/order i for atio uu w absolute axi u rati gs w ww u note a: the polarity of the amplifier is indicated by the 0 or 1 in the part number. an lt1025 with a 0 identifier is properly matched with an ltka00,while an lt1025 with a 1 identifier should be used with an ltka01. consult factory for parts specified with wider operating temperature ranges. order part number kit ltk001cn8ltk001acn8 ltk001mj8 ltk001amj8 t jmax = 100 c, ja = 130 c/w (n8) t jmax = 150 c, ja = 150 c/w, jc = 45 c/w 12 3 4 87 6 5 top view e n8 package 8-lead pdip compensator (lt1025) t jmax = 150 c, ja = 100 c/w (j8) j8 package 8-lead cerdip compensator (lt1025) v o 10mv/ c 60.9 v/ c gnd v in j51.7 v/ c k,t40.6 v/ c r,s6 v/ c r common order part number amplifier only (note a) ltka00cn8ltka01cn8 12 3 4 87 6 5 top view v os trim ?n+in v v os trim v + outover comp n8 package 8-lead pdip amplifier (ltka0x) order part number amplifier only (note a) ltka00mhltka01mh top view v + v os trim v os trim in out over comp +in v 8 7 6 5 3 2 1 4 h package 8-lead to-5 metal can amplifier (ltka0x) + t jmax = 100 c, ja = 130 c/w consider the n8 package for alternate source obsolete package obsolete package (note 1) both devicesoperating temperature range ltk001amj8, ltk001mj8 (obsolete) ......................................................... 55 c to 125 c ltk001acn8, ltk001cn8 ...................... 0 c to 70 c storage temperature range ................. 65 c to 150 c lead temperature range (soldering, 10 sec.)...... 300 c downloaded from: http:///
3 ltk001 001fa t a = 25 c, v s = 15v (amplifier), v s = 5v (compensator) ltk001a ltk001 parameter conditions min typ max min typ max units total temperature error at 25 c type e 0.75 2.5 c (note 3) type j 0.75 2.5 c type k, t 0.86 2.5 c type r, s (note 12) 5.0 5.0 c slope error (notes 4 and 9) 0 c t j 70 c type e 0.05 0.09 c/ c type j 0.06 0.09 c/ c type k, t 0.07 0.10 c/ c type r, s 0.28 0.32 c/ c total temperature error at 0 c t j 70 c type e 2.0 5 c temperature extremes (note 9) type j 2.1 5 c type k, t 2.6 5.2 c type r, s (note 12) 16 16 c ?55 c t j 125 c type e 6 8.5 c type j 6 8.5 c type k, t 6.3 9 c type r, s (note 12) 30 30 c temperature error change with 0.1 0.1 c/v supply voltage (note 5) supply current 480 900 480 900 a electrical characteristics (matched amplifier and compensator) downloaded from: http:///
4 ltk001 001fa compensator (lt1025) parameter conditions min typ max units temperature error at 10mv/ c output (note 9) t j = 25 c, ltk001a 0.3 0.5 c t j = 25 c, ltk001 0.5 2.0 c full temperature span temperature error at individual outputs (note 10) ltk001a: e, j, k, t 0.4 0.75 c ltk001a: r, s 0.4 1.5 c ltk001: e, j, k, t 0.8 2.4 c ltk001: r, s 1.2 3.5 c full temperature span supply current 4v v in 36v 80 100 a 0 c t j 70 c 150 a ?55 c t j 125 c 200 a change in supply current 4v v in 36v 0.01 0.05 a/v line regulation (note 11) 4v v in 36v 0.003 0.02 c/v 10mv/ c output load regulation (note 11) 0 i o 1ma 0.04 0.2 c 10mv/ c output divider impedance e 2.5 k ? j 2.1 k ? k, t 4.4 k ? r, s 3.8 k ? electrical characteristics the denotes the specifications which apply over the full operating temperature range, otherwise specifications are at t a = 25 c. v s = 5v unless otherwise noted. (compensator lt1025) see curve on lt1025 data sheet see curve on lt1025 data sheet downloaded from: http:///
5 ltk001 001fa amplifier (ltka0x) parameter conditions min typ max units input offset voltage 10 35 v input 0ffset voltage drift with temperature (note 6) 0.3 1.5 v/ c input bias current 0 c t a 70 c 200 600 pa ?55 c t a 125 c 300 1500 pa input bias current drift with temperature (note 6) 1 5 pa/ c lnput 0ffset current 0 c t a 70 c 100 500 pa ?55 c t a 125 c 200 700 pa lnput offset current drift with temperature (note 6) 0.6 4 pa/ c large signal voltage gain r l = 10k ? 400 2000 v/mv common mode rejection ratio v cm = 13.5v 106 130 db power supply rejection ratio 2.5v v s 20v (note 5) 106 125 db common mode input voltage range notes 6, 7 above v 0.75 v below v + 1.0 v output voltage swing (notes 6, 8) referred to supplies i out = 0.1ma 0.8 v i out = 1ma 1.1 v supply current 400 800 a supply voltage range total v + to v voltage 4.5 40 v note 1: absolute maximum ratings are those values beyond which the life of a device may be impaired.note 2: the inputs of the ltka0x amplifier are clamped with diodes, so a differential voltage rating does not apply.note 3: total temperature error is the overall error at 25 c taking into account the offset of the amplifier, the offset at the compensator 10mv/ c output, and the error in the compensator divider network. warmup drift isnot included. note 4: slope error is the increase in total temperature error as ambient temperature is increased. it is guaranteed by design and by other tests,but is not tested directly. note 5: this is a worst-case limit assuming that any or all supply voltages change.note 6: guaranteed, but not tested. note 7: by referring common mode range to the supplies, the range referred to ground can be quickly calculated for any given supply voltage.with a single 5v supply, for instance, which has a worst-case low value of 4.7v, the upper common mode limit is 4.7v 1v = 3.7v. the lower common mode limit is 0v + 0.75v = 0.75v. with 15v supplies, the limits would be 14v and 14.25v, respectively. common mode range has a temperature sensitivity of 2mv/ c. note 8: absolute output voltage swing is calculated by subtracting the given limits from actual supply voltage. these limits indicate the pointwhere offset voltage has changed suddenly by 5 v. note 9: temperature error is defined as the deviation from the following formula: v out = (t) + (t 25 c) 2 = typical thermocouple seebeck coefficient as follows, e = 60.9 v/ c, j = 51.7 v/ c, k, t = 40.6 v/ c, r, s = 5.95 v/ c. = 10mv/ c at the 10mv output. = nonlinearity coefficient built into the lt1025 to help compensate for the nonlinearities of thermocouples. = 5.5 x 10 ? , generating 0.34 c bow for 25 c temperature change, and 1.36 c bow for 50 c change. note 10: temperature error at the individual outputs is the sum of the 10mv/ c output error plus the resistor divider error. note 11: line and load regulation do not take into account the effects of self-heating. output changes due to self-heating can be calculated asfollows: ? v out (line) = ? v in (i q + i load )(150 c/w) ? v out (load) = ( ? i load) (v in )(150 c/w) = lt1025 supply current load regulation is 30 a i o 1ma for t a 0 c. note 12: larger errors with type r and s thermocouples are due mostly to 35 v offset of the amplifier. this error can be reduced to 5 v max with the ltc 1050 or ltc1052 operational amplifiers. electrical characteristics the denotes the specifications which apply over the full operating temperature range, otherwise specifications are at t a = 25 c. v s = 15v, v cm = 0v, t j = 25 c unless otherwise noted. (amplifier ltka0x) downloaded from: http:///
6 ltk001 001fa obsolete package u package descriptio .050 (1.270) max .016 ?.021** (0.406 ?0.533) .010 ?.045* (0.254 ?1.143) seating plane .040 (1.016) max .165 ?.185 (4.191 ?4.699) gaugeplane referenceplane .500 ?.750 (12.700 ?19.050) .305 ?.335 (7.747 ?8.509) .335 ?.370 (8.509 ?9.398) dia .200 (5.080) typ .027 ?.045 (0.686 ?1.143) .028 ?.034 (0.711 ?0.864) .110 ?.160 (2.794 ?4.064) insulating standoff 45 h8(to-5) 0.200 pcd 0204 lead diameter is uncontrolled between the reference plane and the seating plane for solder dip lead finish, lead diameter is .016 ?.024 (0.406 ?0.610) * ** pin 1 h package 8-lead to-5 metal can (.200 inch pcd) (reference ltc dwg # 05-08-1320) downloaded from: http:///
7 ltk001 001fa obsolete package information furnished by linear technology corporation is believed to be accurate and reliable. however, no responsibility is assumed for its use. linear technology corporation makes no represen-tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. u package descriptio j8 0801 .014 ?.026 (0.360 ?0.660) .200 (5.080) max .015 ?.060 (0.381 ?1.524) .125 3.175 min .100 (2.54) bsc .300 bsc (7.62 bsc) .008 ?.018 (0.203 ?0.457) 0 ?15 .005 (0.127) min .405 (10.287) max .220 ?.310 (5.588 ?7.874) 12 3 4 87 65 .025 (0.635) rad typ .045 ?.068 (1.143 ?1.650) full lead option .023 ?.045 (0.584 ?1.143) half lead option corner leads option (4 plcs) .045 ?.065 (1.143 ?1.651) note: lead dimensions apply to solder dip/plate or tin plate leads j8 package 8-lead cerdip (narrow .300 inch, hermetic) (reference ltc dwg # 05-08-1110) downloaded from: http:///
8 ltk001 001fa linear technology corporation 1630 mccarthy blvd., milpitas, ca 95035-7417 (408) 432-1900 fax: (408) 434-0507 www.linear-tech.com lt/lt 0305 rev a ? printed in usa ? linear technology corporation 2001 u package descriptio n8 1002 .065 (1.651) typ .045 ?.065 (1.143 ?1.651) .130 .005 (3.302 0.127) .020 (0.508) min .018 .003 (0.457 0.076) .120 (3.048) min 12 3 4 87 6 5 .255 .015* (6.477 0.381) .400* (10.160) max .008 ?.015 (0.203 ?0.381) .300 ?.325 (7.620 ?8.255) .325 +.035?015 +0.889 0.381 8.255 () note:1. dimensions are inches millimeters *these dimensions do not include mold flash or protrusions. mold flash or protrusions shall not exceed .010 inch (0.254mm) .100 (2.54) bsc part number description comments lt1012 picoamp input current amplifier v os = 120 v max, i os = 280pa max lt1025 thermocouple cold junction comparator micropower, 0.5 c initial accuracy ltc1050 zero drift amplifier v os = 5 v max, a vol = 1v/ v max ltc2050 sot-23 zero drift amplifier v os = 3 v max related parts n8 package 8-lead pdip (narrow .300 inch) (reference ltc dwg # 05-08-1510) downloaded from: http:///
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