DDC1128 Datasheet, PDF (1/9 Pages) Texas Instruments – 128-Channel, Current-Input Analog-to-Digital Converter

Product
Folder
Sample &
Buy
Technical
Documents
Tools &
Software
Support &
Community
DDC1128
SLASE36A – MARCH 2014 – REVISED MAY 2016
DDC1128 128-Channel, Current-Input Analog-to-Digital Converter
1 Features
•1 Single-Chip Solution to Directly Measure
128 Low-Level Currents
• Proven High-Precision, True Integrating
Architecture with 100% Charge Collection
• Easy Upgrade for Existing DDC Family
Applications
• Low Power: 3 mW/channel at 3 kSPS
• Extremely Linear:
INL = ±0.025% of Reading ±1 ppm of FSR
• Low Noise: 6.3 ppm of FSR
• Adjustable Full-Scale Range
• Adjustable Speed
– Data Rates up to 6 kSPS with 20-bit
Performance
– Integration Times as low as 160 μs
• Daisy-Chainable Serial Interface
• In-Package Bypass Capacitors Simplify PCB
Design Area and Design Complexity
2 Applications
• CT Scanner DAS
• Photodiode Sensors
• X-Ray Detection Systems
3 Description
The DDC1128 is a 20-bit, 128-channel, current-input
analog-to-digital (A/D) converter. It combines both
current-to-voltage and A/D conversion so that 128
separate low-level current output devices, such as
photodiodes, can be directly connected to its inputs
and digitized.
For each of the 128 inputs, the DDC1128 uses the
proven dual switched integrator front-end. This
configuration allows for continuous current
integration: while one integrator is being digitized by
the onboard A/D converter, the other is integrating
the input current. This architecture provides both a
stable offset and a loss-less collection of the input
current. Adjustable integration times range from
160μs to 1s, allowing currents from fAs to μAs to be
continuously measured with outstanding precision.
The DDC1128 has a serial interface designed for
daisy-chaining in multi-device systems. Simply
connect the output of one device to the input of the
next to create the chain. Common clocking feeds all
the devices in the chain so that the digital overhead
in a multi-DDC1128 system is minimal.
The DDC1128 operates from a +5 V analog supply
and a 2.7 V to 3.6 V digital supply, it is specified from
0°C to 70°C operating temperature and it is available
in a 9 x 9 mm² 192-ball BGA, which includes on
board bypass capacitors to help minimize the external
component requirements and further reduce board
space.
To request a full data sheet or other design
resources: request DDC1128
Device Information
ORDER NUMBER
PACKAGE
BODY SIZE
DDC1128
NFBGA (192) 9.00 mm x 9.00 mm
SPACER
REF3040 OPA350
VREF Buffer
Simplified Schematic
AVDD DVDD
IN1
IN128
VREF
Configuration
and
Control
Serial
Interface
DDC1128
CLK
CONV
DIN_CFG
CLK_CFG
RESET
DVALID
DCLK
DIN
DOUT
To/From
Controller
QGND
AGND DGND
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.