TC7129 - Microchip Technology

1 2002-2012 Microchip Technology 1TC7129 Features: Count Resolution: 19,999 Resolution on 200 mV Scale: 10 V True Differential Input and Reference Low Power Consumption: 500 A at 9V Direct LCD Driver for 4-1/2 Digits, Decimal Points,Low Battery Indicator, and Continuity Indicator Overrange and Underrange Outputs Range Select Input: 10:1 High Common Mode Rejection Ratio: 110 dB External Phase Compensation Not RequiredApplications: Full-Featured Multimeters Digital Measurement DevicesDevice Selection TableGeneral Description:The TC7129 is a 4-1/2 digit Analog-to-Digital Converter(ADC) that directly drives a multiplexed Liquid CrystalDisplay (LCD).

2 Fabricated in high-performance, low-power CMOS, the TC7129 ADC is designed specifi-cally for high-resolution, battery-powered digital multi-meter applications. The traditional dual-slope methodof A/D conversion has been enhanced with a succes-sive integration technique to produce readings accu-rate to better than of full-scale and resolutiondown to 10 V per TC7129 includes features important to multimeterapplications. It detects and indicates low battery condi-tion. A continuity output drives an annunciator on thedisplay and can be used with an external driver to soundan audible alarm.

3 Overrange and underrange outputs,along with a range-change input, provide the ability tocreate auto-ranging instruments. For snapshot read-ings, the TC7129 includes a latch-and-hold input tofreeze the present reading. This combination of featuresmakes the TC7129 the ideal choice for full-featuredmultimeter and digital measurement ApplicationPackage CodePin LayoutPackageTemperatureRangeTC7129 CPLN ormal40-Pin PDIP 0 C to +70 CTC7129 CKWF ormed44-Pin PQFP 0 C to +70 CTC7129 CLW 44-Pin PLCC 0 C to +70 CTC7129 1234567891011121314151617181920403938373 635343332313029 28272625242322219V++Low Battery ContinuityV+5 pF120 kHz10 F20 k F100 k 1 F150 k 10 k V+VIN +**Note.

4 RC network between pins 26 and 28 is not k 4-1/2 Digit Analog-to-Digital Converters with On-Chip LCD DriversTC7129DS21459E-page 2 2002-2012 Microchip Technology Types33343536373839131098718 19 20 2123 2465431442224342414025262728321431153016 29171112TC7129 CLWF1, E1, DP1B2, C2, BATTA2, G2, D2F2, E2, DP2B3, C3, MINUSA3, G3, D3F3, E3, DP3B4, C4, BC5A4, G4, D4F4, E4, DP4 NCREF LOREF HIIN HIIN LOBUFF CREF-CREF+COMMON CONTINUITYINT OUTNCA1, G1, D1B1, C1, CONTANNUNCIATOROSC3 OSC1 NCOSC2DP1DP2 RANGEDGNDBP3BP2BP1 VDISPDP4/ORNCDP3/URLATCH/HOLDV+V-INT IN2728293031323374321TC7129 CKW12 13 14 1517 1844 43 42 4139 38401637363534192021222682592410231156A1 , G1, D1B1, C1, CONTANNUNCIATOROSC3 OSC1 NCOSC2DP1DP2 RANGEDGNDREF LOREF HIIN HIIN LOBUFF CREF-CREF+COMMON CONTINUITYINT OUTNCF1, E1, DP1B2, C2, BATTA2, G2, D2F2, E2, DP2B3, C3, MINUSA3, G3, D3F3, E3, DP3B4, C4, BC5A4, G4, D4F4, E4.

5 DP4 NCBP3BP2BP1 VDISPDP4/ORNCDP3/URLATCH/HOLDV+V-INT INTC7129 CPL 40-Pin PDIP44-Pin QFP44-Pin PLCC123456789101112131415161718192040393 8373635343332313029 2827262524232221 OSC2DP1DP2 RANGEDGNDREF LOREF HIIN HIIN LOBUFF CREF-CREF+COMMONCONTINUITYINT OUTINT INV+V-DP3/UROSC1 OSC3 ANNUNICATORB1, C1, CONTA1, G1, D1F1, E1, DP1B2, C2, LO BATTA2, G2, D2F2, E2, DP2B3, C3, MINUSA3, G3, D3F3, E3, DP3B4, C4, BC5A4, G4, D4F4, E4, DP4BP3BP2BP1 VDISPDP4/ORDisplayOutputLinesLATCH/HOLD 2002-2012 Microchip Technology CHARACTERISTICSA bsolute Maximum Ratings*Supply Voltage (V+ to V-) .. 15 VReference Voltage (REF HI or REF LO).

6 V+ to V Input Voltage (IN HI or IN LO) (Note 1).. V+ to V V+ to (DGND )Digital Input (Pins 1, 2, 19, 20, 21, 22, 27, 37, 39, 40) .. DGND to V+Analog Input (Pins 25, 29, 30) .. V+ to V Package Power Dissipation (TA 70 C) Plastic DIP .. PLCC .. Plastic QFP .. Temperature Range .. 0 C to +70 CStorage Temperature Range .. -65 C to +150 C*Stresses above those listed under Absolute MaximumRatings may cause permanent damage to the device. Theseare stress ratings only and functional operation of the deviceat these or any other conditions above those indicated in theoperation sections of the specifications is not to Absolute Maximum Rating conditions forextended periods may affect device ELECTRICAL SPECIFICATIONSE lectrical Characteristics: V+ to V = 9V, VREF = 1V, TA = +25 C, fCLK = 120 kHz, unless otherwise indicated.

7 Pin numbers refer to 40-pin TypMaxUnitTest ConditionsInputZero Input Reading 0000 0000+0000 Counts VIN = 0V, 200 mV scaleZero Reading Drift V/ CVIN = 0V, 0 C < TA < +70 CRatiometric Reading9996 10000 Counts VIN = VREF = 1000 mV, Range = 2 VRange Change = 1V on High Range, VIN = on Low RangeRERollover Error 12 Counts VIN = VIN+ = 199 mVNLL inearity Error 1 Counts 200mV ScaleCMRRC ommon Mode Rejection Ratio 110 dBVCM = 1V, VIN = 0V, 200 mV scaleCMVRC ommon Mode Voltage Range (V-) + VVIN = 0V (V+) 1 V200 mV scaleeNNoise (Peak-to-Peak Value notExceeded 95% of Time) 14 VP-PVIN = 0V200 mV scaleIINI nput Leakage Current 110pAVIN = 0V, pins 32, 33 Scale Factor Temperature Coefficient 27ppm/ C VIN = 199 mV, 0 C < TA < +70 CExternal VREF = 0 ppm/ CNote 1:Input voltages may exceed supply voltages, provided input current is limited to 400 A.

8 Currents above this value may result in invalid display readings, but will not destroy the device if limited to 1 mA. Dissipation ratings assume device is mounted with all leads soldered to printed circuit 4 2002-2012 Microchip Technology + to pin 28 Common Sink Current mA Common = + Source Current 10 A Common = Ground + to pin 36, V+ to V = 9 VSink Current mA DGND = + Voltage Range6 912VV+ to V ISSupply Current Excluding Common Current + to V = 9 VfCLKC lock Frequency 120360kHzVDISP Resistance 50 k VDISP to V+Low Battery Flag Activation + to V DigitalContinuity Comparator Threshold Voltages100 200 mVVOUT pin 27 = High 200400mVVOUT pin 27 = LowPull-down Current 210 APins 37, 38.

9 39 Weak Output Current Sink/Source 3/3 APins 20, 21 sink/source 3/9 APin 27 sink/sourcePin 22 Source Current 40 APin 22 Sink Current 3 ATC7129 ELECTRICAL SPECIFICATIONS (CONTINUED)Electrical Characteristics: V+ to V = 9V, VREF = 1V, TA = +25 C, fCLK = 120 kHz, unless otherwise indicated. Pin numbers refer to 40-pin TypMaxUnitTest ConditionsNote 1:Input voltages may exceed supply voltages, provided input current is limited to 400 A. Currents above this value may result in invalid display readings, but will not destroy the device if limited to 1 mA. Dissipation ratings assume device is mounted with all leads soldered to printed circuit board.

10 2002-2012 Microchip Technology DESCRIPTIONSD escriptions of the pins are listed in Table 2-1:PIN FUNCTION TABLEPin PDIPPin PQFPPin PLCCS ymbolFunction1402 OSC1 Input to first clock of second clock square wave output for driving 5B1, C1, CONTO utput to display 6A1, G1, D1 Output to display 7F1, E1, DP1 Output to display 8B2, C2, LO BATTO utput to display 9A2, G2, D2 Output to display , E2, DP2 Output to display , C3, MINUSO utput to display , G3, D3 Output to display , E3, DP3 Output to display , C4, BC5 Output to display , D4, G4 Output to display , E4, DP4 Output to display #3 output to #2 output to #1 output to rail for display.