TC850 15-Bit, Fast Integrating CMOS A/D Converter Features Package Types 15-bit Resolution Plus Sign Bit 40-Pin PDIP/CERDIP Up to 40 Conversions per Second CS 1 40 V DD Integrating ADC Technique CE 2 39 REF + 1 WR 38 C + 3 REF1 - Monotonic RD 4 37 C - REF1 - High Noise Immunity REF- CONT/DEMAND 5 36 - Auto Zeroed Amplifiers Eliminate Offset OVR/POL C - 6 35 REF2 Trimming L/H 34 C + 7 REF2 TC850CPL Wide Dynamic Range: 96dB DB7 8 33 REF + 2 TC850IJL 9 IN+ DB6 32 Low Input Bias Current: 30pA 10 31 DB5 IN- ANALOG Low Input Noise: 30 V P-P 11 30 DB4 COMMON C DB3 12 29 Sensitivity: 100 V INTB 13 28 C DB2 INTA Flexible Operational Control DB1 14 27 C BUFA Continuous or On Demand Conversions DB0 15 26 C BUFB 25 BUSY 16 BUFFER Data Valid Output 17 24 OSC INT 1 IN Bus Compatible, 3-State Data Outputs OSC 18 23 2 INT OUT TEST 19 22 V SS -8-BitDataBus 20 21 COMP DGND -Simple P Interface - Two Chip Enables 44-Pin PLCC - Read ADC Result Like Memory 5V Power Supply Operation: 20m 40-Pin Dual-in-Line or 44-Pin PLCC Packages Applications 65 4 3 2 1 44 43 42 41 40 Precision Analog Signal Processor 7 39 C - OVR/POL REF2 C + 8 38 Precision Sensor Interface L/H REF2 REF + 9 37 DB7 2 High Accuracy DC Measurements DB6 10 36 IN+ 11 35 DB5 IN- Device Selection Table TC850CLW NC 12 TC850ILW 34 NC ANALOG Temperature DB4 13 33 COMMON Part Number Package Range C 14 32 DB3 INTB 15 31 C DB2 INTA TC850CPL 40-Pin PDIP 0Cto+70C DB1 16 30 C BUFA TC850IJL 40-Pin CERDIP -25Cto+85C C DB0 17 29 BUFB TC850CLW 44-Pin PLCC 0Cto+70C 18 19 20 21 22 23 24 25 26 27 28 TC850ILW 44-Pin PLCC -25Cto+85C NC = No Internal Connection 2002 Microchip Technology Inc. DS21479B-page 1 BUSY CONT/DEMAND OSC 1 RD WR OSC 2 CE TEST CS DGND NC NC V COMP DD V REF + SS 1 INT C + OUT REF1 INT C - IN REF1 BUFFER REF-TC850 need for precision external amplifiers. The internal General Description amplifiers are auto zeroed, ensuring a zero digital out- The TC850 is a monolithic CMOS A/D converter (ADC) put, with 0V analog input. Zero adjustment with resolution of 15-bits plus sign. It combines a chop- potentiometers or calibrations are not required. per-stabilized buffer and integrator with a unique multi- The TC850 outputs data on an 8-bit, 3-state bus. Digital ple-slope integration technique that increases inputs are CMOS compatible while outputs are TTL/ conversion speed. The result is 16 times improvement CMOS compatible. Chip-enable and byte-select inputs, in speed over previous 15-bit, monolithic integrating combined with an end-of-conversion output, ensures ADCs (from 2.5 conversions per second up to 40 per easy interfacing to a wide variety of microprocessors. second). Faster conversion speed is especially wel- Conversions can be performed continuously or on come in systems with human interface, such as digital command. In continuous mode, data is read as three scales. consecutive bytes and manipulation of address lines is The TC850 incorporates an ADC and a P-compatible not required. digital interface. Only a voltage reference and a few, Operating from 5V supplies, the TC850 dissipates noncritical, passive components are required to form a only 20m . The TC850 is packaged in a 40-pin plastic complete 15-bit plus sign ADC. CMOS processing pro- or ceramic dual-in-line package (DIPs) and in a 44-pin vides the TC850 with high-impedance, differential plastic leaded chip carrier (PLCC), surface-mount inputs. Input bias current is typically only 30pA, permit- package. ting direct interface to sensors. Input sensitivity of 100 V per least significant bit (LSB) eliminates the Functional Block Diagram Pinout of 40-Pin Package R C INT INT REF + 2 5V +5V REF + REF- 1 INT OUT BUF INT IN 39 34 36 25 24 23 22 40 - 32 IN+ + Comparator - 31 Analog IN- Buffer + Mux 30 + COMMON - Integrator TC850 6-Bit 9-Bit Up/Down Up/Down A/D Counter Counter Control Sequencer Data Latch 4 Bus Interface Octal 2-Input Mux Clock Decode Logic Oscillator 3-State Data Bus 17 18537 6 4 1 2 15 8 OSC OSC CONT/ L/HOVR/ WR RD CS CE DB0 DB7 1 2 DEMAND POL DS21479B-page 2 2002 Microchip Technology Inc.