TC7129 4-1/2 Digit Analog-to-Digital Converters with On-Chip LCD Drivers Features: General Description: Count Resolution: 19,999 The TC7129 is a 4-1/2 digit Analog-to-Digital Converter (ADC) that directly drives a multiplexed Liquid Crystal Resolution on 200 mV Scale: 10 V Display (LCD). Fabricated in high-performance, low- True Differential Input and Reference power CMOS, the TC7129 ADC is designed specifi- Low Power Consumption: 500 A at 9V cally for high-resolution, battery-powered digital multi- Direct LCD Driver for 4-1/2 Digits, Decimal Points, meter applications. The traditional dual-slope method Low Battery Indicator, and Continuity Indicator of A/D conversion has been enhanced with a succes- Overrange and Underrange Outputs sive integration technique to produce readings accu- rate to better than 0.005% of full-scale and resolution Range Select Input: 10:1 down to 10 V per count. High Common Mode Rejection Ratio: 110 dB The TC7129 includes features important to multimeter External Phase Compensation Not Required applications. It detects and indicates low battery condi- tion. A continuity output drives an annunciator on the Applications: display and can be used with an external driver to sound Full-Featured Multimeters an audible alarm. Overrange and underrange outputs, along with a range-change input, provide the ability to Digital Measurement Devices create auto-ranging instruments. For snapshot read- ings, the TC7129 includes a latch-and-hold input to Device Selection Table freeze the present reading. This combination of features Package Pin Temperature makes the TC7129 the ideal choicefor full-featured Package Code Layout Range multimeter and digital measurement applications. TC7129CPL Normal 40-Pin PDIP 0 C to +70C TC7129CKW Formed 44-Pin PQFP 0 C to +70C TC7129CLW 44-Pin PLCC 0 C to +70C Typical Application Low Battery Continuity V+ 5 pF 20 11 10 9 7 6 5 4 3 2 1 19 18 17 16 15 14 13 12 8 120 kHz TC7129 30 31 32 34 35 37 38 39 40 21 22 23 24 25 26 27 28 29 33 36 330 k * 0.1 F 10 pF 0.1 + F 20 1 F 0.1 F k V+ 150 k + 10 k 9V 100 k + V IN *Note: RC network between pins 26 and 28 is not required. 2002-2012 Microchip Technology Inc. DS21459E-page 1TC7129 Package Types 40-Pin PDIP OSC1 1 40 OSC2 OSC3 2 39 DP 1 38 ANNUNICATOR 3 DP 2 B , C , CONT 4 37 1 1 RANGE A , G , D 5 36 DGND 1 1 1 F , E , DP REF LO 1 1 1 6 35 B , C , LO BATT 34 REF HI 2 2 7 A , G , D IN HI 2 2 2 8 33 F , E , DP 9 32 2 2 2 IN LO 10 31 BUFF B , C MINUS 3 3 TC7129CPL , Display A , G , D C - 11 30 3 3 3 REF Output F , E , DP 29 Lines 3 3 3 12 C + REF B , C BC 13 28 COMMON 4 4, 5 A , G , D 4 4 4 14 27 CONTINUITY F , E , DP 15 26 INT OUT 4 4 4 16 25 INT IN BP 3 BP 17 24 V+ 2 18 23 V- BP 1 V 19 22 LATCH/HOLD DISP DP /OR 20 21 DP /UR 4 3 44-Pin QFP 44-Pin PLCC 6 543 2 1 44 43 42 41 40 44 43 42 41 40 39 38 37 36 35 34 F , E , DP 33 F , E , DP 7 39 REF LO 1 1 1 1 REF LO 1 1 1 REF HI 2 32 REF HI 8 38 B , C , BATT B , C , BATT 2 2 2 2 A , G , D A , G , D IN HI 3 31 IN HI 9 37 2 2 2 2 2 2 F , E , DP F , E , DP 4 30 10 36 IN LO 2 2 2 IN LO 2 2 2 B , C MINUS 29 B , C MINUS 11 35 5 BUFF BUFF 3 3, 3 3, 12 34 NC 6 28 NC NC NC TC7129CKW TC7129CLW A , G , D A , G , D C - 7 27 C - 13 33 3 3 3 REF 3 3 3 REF F , E , DP F , E , DP 8 26 C + 14 32 C + 3 3 3 3 3 3 REF REF B , C BC B , C BC 9 25 15 31 COMMON 4 4, 5 COMMON 4 4, 5 A , G , D A , G , D 10 24 16 30 CONTINUITY 4 4 4 CONTINUITY 4 4 4 F , E , DP 11 23 INT OUT F , E , DP 17 29 INT OUT 4 4 4 4 4 4 25 26 27 28 18 19 20 21 22 23 24 19 20 21 22 12 13 14 15 16 17 18 DS21459E-page 2 2002-2012 Microchip Technology Inc. BP A , G , D 3 1 1 1 BP B , C , CONT 2 1 1 BP 1 ANNUNCIATOR V OSC3 DISP OSC1 DP /OR 4 NC NC OSC2 DP /UR 3 DP LATCH/HOLD 1 DP V- 2 RANGE V+ INT IN DGND BP A , G , D 3 1 1 1 BP B , C , CONT 2 1 1 BP 1 ANNUNCIATOR V OSC3 DISP OSC1 DP /OR 4 NC NC OSC2 DP /UR 3 DP 1 LATCH/HOLD DP V- 2 RANGE V+ DGND INT IN