DDC3256 Series
256 channel, 20-kSPS current-input analog-to-digital converter
Manufacturer: Texas Instruments
Catalog
256 channel, 20-kSPS current-input analog-to-digital converter
Key Features
• Single-chip solution to directly measure 256 low-level currents simultaneouslyAdjustable full-scale charge range up to 320 pCInput current: 1 µA (maximum)Adjustable speed with integration times as low as 50 µs (20 KSPS per channel)Resolution: 24 bitLow power dissipation: 1.2 mW/channelIntegral non-linearity: ±0.025% of reading ±1 ppm of full scale range (all channels active)Low noise: 0.26 fCrms at 320 pC FSR with 20 pF sensor capacitanceNo charge lossOn-chip temperature sensorSerial LVDS output interfaceSingle 1.85-V supplyIn-package bypass capacitors and reference buffer to reduce PCB area and design complexitySingle-chip solution to directly measure 256 low-level currents simultaneouslyAdjustable full-scale charge range up to 320 pCInput current: 1 µA (maximum)Adjustable speed with integration times as low as 50 µs (20 KSPS per channel)Resolution: 24 bitLow power dissipation: 1.2 mW/channelIntegral non-linearity: ±0.025% of reading ±1 ppm of full scale range (all channels active)Low noise: 0.26 fCrms at 320 pC FSR with 20 pF sensor capacitanceNo charge lossOn-chip temperature sensorSerial LVDS output interfaceSingle 1.85-V supplyIn-package bypass capacitors and reference buffer to reduce PCB area and design complexity
Description
AI
The DDC3256 is a 24-bit, 256-channel, current-input analog-to-digital (A/D) converter. It combines both, current-to-voltage conversion by current integration, and A/D conversion.
Up to 256 individual low-level current output devices, such as photodiodes, can be directly connected to its inputs and digitized in parallel (simultaneously).
For each of the 256 inputs, the device has one low noise and low power integrator designed to capture all the charge from the sensor. The integration time is adjustable from 50 µs to 1.6 ms, allowing currents in the order of fA to µA to be continuously measured with outstanding precision. The outputs of the integrators are digitized by on-chip low power ADCs and the converted digital codes are transmitted over a single LVDS pair designed to minimize noise coupling in environments with high channel count.
The DDC3256 operates from single 1.85-V supply. The device is specified from 0°C to 70°C operating temperature and available in a 13.2 × 17.2 mm 2 336-ball 0.8 mm-pitch BGA. The on-chip reference buffer and bypass capacitors (on the BGA) help minimize the external component requirements and further reduce board space.
The DDC3256 is a 24-bit, 256-channel, current-input analog-to-digital (A/D) converter. It combines both, current-to-voltage conversion by current integration, and A/D conversion.
Up to 256 individual low-level current output devices, such as photodiodes, can be directly connected to its inputs and digitized in parallel (simultaneously).
For each of the 256 inputs, the device has one low noise and low power integrator designed to capture all the charge from the sensor. The integration time is adjustable from 50 µs to 1.6 ms, allowing currents in the order of fA to µA to be continuously measured with outstanding precision. The outputs of the integrators are digitized by on-chip low power ADCs and the converted digital codes are transmitted over a single LVDS pair designed to minimize noise coupling in environments with high channel count.
The DDC3256 operates from single 1.85-V supply. The device is specified from 0°C to 70°C operating temperature and available in a 13.2 × 17.2 mm 2 336-ball 0.8 mm-pitch BGA. The on-chip reference buffer and bypass capacitors (on the BGA) help minimize the external component requirements and further reduce board space.