DATASHEET ICL7135 FN3093 Rev.4.00 4 1/2 Digit, BCD Output, A/D Converter Aug 28, 2007 The Intersil ICL7135 precision A/D converter, with its Features multiplexed BCD output and digit drivers, combines dual- Accuracy Guaranteed to 1 Count Over Entire20000 slope conversion reliability with 1 in 20,000 count accuracy Counts (2.0000V Full Scale) and is ideally suited for the visual display DVM/DPM market. The 2.0000V full scale capability, auto-zero, and auto- Guaranteed Zero Reading for 0V Input polarity are combined with true ratiometric operation, almost 1pA Typical Input Leakage Current ideal differential linearity and true differential input. All True Differential Input necessary active devices are contained on a single CMOS lC, with the exception of display drivers, reference, and a True Polarity at Zero Count for Precise Null Detection clock. Single Reference Voltage Required The ICL7135 brings together an unprecedented combination Overrange and Underrange Signals Available for Auto- of high accuracy, versatility, and true economy. It features Range Capability o auto-zero to less than 10 V, zero drift of less than 1V/ C, All Outputs TTL Compatible input bias current of 10pA (Max), and rollover error of less than one count. The versatility of multiplexed BCD outputs is Blinking Outputs Gives Visual Indication of Overrange increased by the addition of several pins which allow it to Six Auxiliary Inputs/Outputs are Available for Interfacing to operate in more sophisticated systems. These include UARTs, Microprocessors, or Other Circuitry STROBE, OVERRANGE, UNDERRANGE, RUN/HOLD and BUSY lines, making it possible to interface the circuit to a Multiplexed BCD Outputs microprocessor or UART. Pb-Free Plus Anneal Available (RoHS Compliant) Ordering Information Pinout TEMP. ICL7135 PART PART RANGE PKG. (PDIP) NUMBER MARKING (C) PACKAGE DWG. TOP VIEW ICL7135CPI ICL7135CPI 0 to +70 28 Ld PDIP E28.6 V- 1 28 UNDERRANGE ICL7135CPIZ ICL7135CPIZ 0 to +70 28 Ld PDIP E28.6 (Note 1) (Pb-free) (Note 2) REFERENCE 2 27 OVERRANGE NALOG COMMON 3 26 STROBE NOTES: INT OUT 4 25 R/H 1. Intersil Pb-free plus anneal products employ special Pb-free material sets molding compounds/die attach materials and AZ IN 5 24 DIGITAL GND 100% matte tin plate termination finish, which are RoHS BUFF OUT 6 23 POL compliant and compatible with both SnPb and Pb-free soldering REF CAP - 7 22 CLOCK IN operations. Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the 21 BUSY REF CAP + 8 Pb-free requirements of IPC/JEDEC J STD-020. IN LO 9 20 (LSD) D1 2. Pb-free PDIPs can be used for through hole wave solder IN HI 10 19 D2 processing only. They are not intended for use in Reflow solder V+ 11 18 D3 processing applications. (MSD) D5 12 17 D4 (LSB) B1 13 16 (MSB) B8 B2 14 15 B4 FN3093 Rev.4.00 Page 1 of 15 Aug 28, 2007ICL7135 Typical Application Schematic SET V = 1.000V REF CLOCK IN -5V 1 28 V IN 120kHz REF 2 27 100k ANALOG 3 26 GND 4 25 0.47F 27 0V ANODE DISPLAY 5 24 100k DRIVER 1 F 6 23 TRANSISTORS 100k 7 22 6 1F ICL7135 21 100K 8 SIGNAL 9 20 INPUT 0.1 F 10 19 +5V 11 18 12 17 13 16 SEVEN 14 15 SEG. DECODE FN3093 Rev.4.00 Page 2 of 15 Aug 28, 2007