Document
TC7109/A
12-Bit A-Compatible Analog-to-Digital Converters
Features:
• Zero Integrator Cycle for Fast Recovery from Input Overloads
• Eliminates Cross-Talk in Multiplexed Systems • 12-Bit Plus Sign Integrating A/D Converter with
Over Range Indication • Sign Magnitude Coding Format • True Differential Signal Input and Differential
Reference Input • Low Noise: 15VP-P Typ. • Input Current: 1pA Typ. • No Zero Adjustment needed • TTL Compatible, Byte Organized Tri-State
Outputs • UART Handshake Mode for simple Serial Data
Transmissions
Device Selection Table
Part Number (TC7109X)*
Package
Temperature Range
TC7109CKW TC7109CLW TC7109CPL TC7109IJL
44-Pin PQFP 44-Pin PLCC 40-Pin PDIP 40-Pin CERDIP
0°C to +70°C 0°C to +70°C 0°C to +70°C -25°C to +85°C
*The “A” version has a higher IOUT on the digital lines.
General Description:
The TC7109A is a 12-bit plus sign, CMOS low power Analog-to-Digital Converter (ADC). Only eight passive components and a crystal are required to form a complete dual slope integrating ADC.
The improved VOH source current and other TC7109A features make it an attractive per-channel alternative to analog multiplexing for many data acquisition applications. These features include typical input bias current of 1pA, drift of less than 1V/°C, input noise typically 15VP-P, and auto-zero. True differential input and reference allow measurement of bridge type transducers, such as load cells, strain gauges and temperature transducers.
The TC7109A provides a versatile digital interface. In the Direct mode, Chip Select and HIGH/LOW byte enable control parallel bus interface. In the Handshake mode, the TC7109A will operate with industry standard UARTs in controlling serial data transmission – ideal for remote data logging. Control and monitoring of conversion timing is provided by the RUN/HOLD input and Status output.
For applications requiring more resolution, see the TC500, 15-bit plus sign ADC data sheet. The TC7109A has improved over range recovery performance and higher output drive capability than the original TC7109. All new (or existing) designs should specify the TC7109A wherever possible.
2002-2012 Microchip Technology Inc.
DS21456D-page 1
TC7109/A
Package Type
44-Pin PQFP
44-Pin PLCC
B12 OR POL STATUS GND NC V+ REF INREF CAPREF CAP+ REF IN+ B12 OR POL STATUS GND NC V+ REF INREF CAPREF CAP+ REF IN+
44 43 42 41 40 39 38 37 36 35 34
B11 1
33 IN HI
B10 2
32 IN LO
B9 3
31 COMMON
B8 4
30 INT
B7 5 NC 6
TC7109ACKW TC7109CKW
29 AZ 28 NC
B6 7
27 BUFF
B5 8
26 REF OUT
B4 9
25 V-
B3 10
24 SEND
B2 11
23 RUN/HOLD
12 13 14 15 16 17 18 19 20 21 22
6 5 4 3 2 1 44 43 42 41 40
B11 7
39 IN HI
B10 8
38 IN LO
B9 9
37 COMMON
B8 10
36 INT
B7 11 NC 12 B6 13
TC7109ACLW TC7109CLW
35 AZ 34 NC 33 BUFF
B5 14
32 REF OUT
B4 15
31 V-
B3 16
30 SEND
B2 17
29 RUN/HOLD
18 19 20 21 22 23 24 25 26 27 28
B1 TEST LBEN HBEN CE/LOAD
NC MODE OSC IN OSC OUT OSC SEL BUFF OSC OUT
B1 TEST LBEN HBEN CE/LOAD
NC MODE OSC IN OSC OUT OSC SEL BUFF OSC OUT
40-Pin PDIP/CERDIP
GND 1 STATUS 2
POL 3
OR 4 B12 5 B11 6 B10 7 B9 8 B8 9 B7 10 B6 11 B5 12 B4 13 B3 14 B2 15
B1 16 TEST 17
LBEN 18 HBEN 19 CE/LOAD 20
TC7109A TC7109
40 V+ 39 REF IN38 REF CAP37 REF CAP+ 36 REF IN+ 35 IN HI 34 IN LO 33 COMMON 32 INT 31 AZ 30 BUFF 29 REF OUT 28 V27 SEND 26 RUN/HOLD 25 BUFF OSC OUT 24 OSC SEL 23 OSC OUT 22 OSC IN 21 MODE
NC = No internal connection
DS21456D-page 2
2002-2012 Microchip Technology Inc.
TC7109/A
Typical Application
TEST POL OR B12 B11 B10 B9 B8 B7 B6 B5 B4 B3 B2 B1
TC7109A
REF REF CREF REF
CAP+ IN+
IN-
37 36
39
REF RINT
CAZ CINT
CAP38
30
BUFF 31
AZ 32
INT
17
High Order Byte Inputs
Low Order Byte Inputs
3 4 5 6 7 8 9 10 11 12 13 14 15 16
Input 35 INT High
AZ AZ ZI ZI
DE DE (–) (+)
Buffer –
+
Integrator – +
Comparator
Comp Out
16 Three-State Outputs 14 Latches
AZ Common 33 Input Low 34 INT
DE DE (+) (–)
AZ DE (±)
ZI
ZI
10mA – +
AZ
To Analog Section
Comp Out AZ INT
DE (±) ZI
12-Bit Counter Latch Clock
Conversion Control Logic
Oscillator and Clock Circuitry
Handshake Logic
6.2V
18 LBEN 19 HBEN 20 CE/LOAD
29 28
REF VOUT
40 V+
2 Status
26 22 23 24 25 21
RUN/ OSC OSC OSC BUFF Mode HOLD IN OUT SEL OSC
OUT
27 Send
1 GND
2002-2012 Microchip Technology Inc.
DS21456D-page 3
TC7109/A
1.0 ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings*
Positive Supply Voltage (GND to V+) ..................+6.2V Negative Supply Voltage (GND to V-) .....................-9V Analog Input Voltage (Low to High) (Note 1).... V+ to VReference Input Voltage:
(Low to High) (Note 1) ............................. V+ to VDigital Input Voltage:
(Pins 2-27) (Note 2) ...........................GND – 0.3V Power Dissipation, TA < 70°C (Note 3)
CERDIP ......................................................2.29W Plastic DIP ..................................................1.23W PLCC ...................................