DDC112 Dual Current Input 20-Bit Analog-To-Digital Converter | TI.com

DDC112 (ACTIVE) Dual Current Input 20-Bit Analog-To-Digital Converter

 

Recommended alternative parts

  • DDC264  - The device has the SAME FUNCTIONALITY as the compared device, but is not pin-for-pin equivalent and may not be parametrically equivalent.   64-Channel, Current-Input Analog-to-Digital Converter
  • DDC232  - The device has the SAME FUNCTIONALITY as the compared device, but is not pin-for-pin equivalent and may not be parametrically equivalent.   32-Channel, Current-Input Analog-to-Digital Converter
  • DDC316  - The device has the SAME FUNCTIONALITY as the compared device, but is not pin-for-pin equivalent and may not be parametrically equivalent.   16-Channel, Current-Input Analog-to-Digital Converter
  • DDC118  - The device has the SAME FUNCTIONALITY as the compared device, but is not pin-for-pin equivalent and may not be parametrically equivalent.   8-Channel, Current-Input Analog-to-Digital Converter
  • DDC114  - The device has the SAME FUNCTIONALITY as the compared device, but is not pin-for-pin equivalent and may not be parametrically equivalent.   4-Channel, Current-Input Analog-to-Digital Converter

Description

The DDC112 is a dual input, wide dynamic range, charge-digitizing analog-to-digital (A/D) converter with 20-bit resolution. Low-level current output devices, such as photosensors, can be directly connected to its inputs. Charge integration is continuous as each input uses two integrators; while one is being digitized, the other is integrating.

For each of its two inputs, the DDC112 combines current-to-voltage conversion, continuous integration, programmable full-scale range, A/D conversion, and digital filtering to achieve a precision, wide dynamic range digital result. In addition to the internal programmable full-scale ranges, external integrating capacitors allow an additional user-settable full-scale range of up to 1000pC.

To provide single-supply operation, the internal A/D converter utilizes a differential input, with the positive input tied to VREF. When the integration capacitor is reset at the beginning of each integration cycle, the capacitor charges to VREF. This charge is removed in proportion to the input current. At the end of the integration cycle, the remaining voltage is compared to VREF.

The high-speed serial shift register which holds the result of the last conversion can be configured to allow multiple DDC112 units to be cascaded, minimizing interconnections. The DDC112 is available in a SO-28 or TQFP-32 package and is offered in two performance grades.

Features

  • MONOLITHIC CHARGE MEASUREMENT ADC
  • DIGITAL FILTER NOISE REDUCTION:
       3.2ppm, rms
  • INTEGRAL LINEARITY:
       ±0.005% Reading ±0.5ppm FSR
  • HIGH PRECISION,TRUE INTEGRATING FUNCTION
  • PROGRAMMABLE FULL SCALE
  • SINGLE SUPPLY
  • CASCADABLE OUTPUT
  • APPLICATIONS
    • DIRECT PHOTOSENSOR DIGITIZATION
    • CT SCANNER DAS
    • INFRARED PYROMETER
    • PRECISION PROCESS CONTROL
    • LIQUID/GAS CHROMATOGRAPHY
    • BLOOD ANALYSIS

Protected by US Patent #5841310
All trademarks are the property of their respective owners.

Parametrics

Compare all products in Computer tomography (CT) AFEs Email Download to Excel
Part number Order Number of input channels Resolution (Bits) Interface Features Operating temperature range (C) Package size: mm2:W x L (PKG) Package Group Approx. price (US$)
DDC112 Order now 2     20     SPI     Computed Tomography (CT)     -40 to 85
0 to 70    
28SOIC: 184 mm2: 10.3 x 17.9 (SOIC | 28)
32TQFP: 81 mm2: 9 x 9 (TQFP | 32)    
SOIC | 28
TQFP | 32    
12.60 | 1ku    
DDC1128 Samples not available 128     20     SPI     Computed Tomography (CT)     0 to 70     192NFBGA: 81 mm2: 9 x 9 (NFBGA | 192)     NFBGA | 192     198.00 | 1ku    
DDC114 Order now 4     20     SPI     Computed Tomography (CT)     -40 to 85     48VQFN: 49 mm2: 7 x 7 (VQFN | 48)     VQFN | 48     17.85 | 1ku    
DDC118 Samples not available 8     20     SPI     Computed Tomography (CT)     -40 to 85     48VQFN: 49 mm2: 7 x 7 (VQFN | 48)     VQFN | 48     30.00 | 1ku    
DDC2256A Samples not available 256     24     LVDS/SPI     Computed Tomography (CT)     0 to 70     323NFBGA: 224 mm2: 14 x 16 (NFBGA | 323)     NFBGA | 323     299.00 | 1ku    
DDC232 Samples not available 32     20     SPI     Computed Tomography (CT)     0 to 70     64NFBGA: 64 mm2: 8 x 8 (NFBGA | 64)     NFBGA | 64     70.00 | 1ku    
DDC264 Order now 64     20     SPI     Computed Tomography (CT)     0 to 70     100NFBGA: 81 mm2: 9 x 9 (NFBGA | 100)     NFBGA | 100     99.00 | 1ku    
DDC316 Samples not available 16     16     SPI     Computed Tomography (CT)     0 to 70     64NFBGA: 64 mm2: 8 x 8 (NFBGA | 64)     NFBGA | 64     48.25 | 1ku