512 Channel, 20KSPS Current Input Analog to Digital Converter | ZWR | 656 | 0 to 70

The DDC3512 is a 24-bit,

512-channel, current-input analog-to-digital (A/D) converter. The

device combines both, current-to-voltage conversion by current

integration, and A/D conversion. The device is a stacked-die version

of DDC3256, with one die of the latter sitting on top of the

other.

Up to 512 individual low-level current output

devices, such as photodiodes, can be directly connected to the

inputs and digitized in parallel (simultaneously).

For each of the 512 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 50µs to

1.6ms, 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 DDC3512 operates from single

1.85V supply. The device is specified from 0°C to 70°C operating

temperature and available in a 13.2 × 17.2mm2 656-ball

0.8mm row-pitch and 0.4mm column-pitch BGA. The on-chip reference

buffer and bypass capacitors (on the BGA) help minimize the external

component requirements and further reduce board space.