LTC2376-20_15 Datasheet, PDF (8/30 Pages) Linear Technology – 20-Bit, 250ksps, Low Power SAR ADC with 0.5ppm INL

LTC2376-20
PIN FUNCTIONS
CHAIN (Pin 1): Chain Mode Selector Pin. When low, the
LTC2376-20 operates in normal mode and the RDL/SDI
input pin functions to enable or disable SDO. When high,
the LTC2376-20 operates in chain mode and the RDL/SDI
pin functions as SDI, the daisy-chain serial data input.
Logic levels are determined by OV_DD.
V_DD (Pin 2): 2.5V Power Supply. The range of V_DD is
2.375V to 2.625V. Bypass V_DD to GND with a 10µF ceramic
capacitor.
GND (Pins 3, 6, 10 and 16): Ground.
IN⁺, IN^– (Pins 4, 5): Positive and Negative Differential
Analog Inputs.
REF (Pin 7): Reference Input. The range of REF is 2.5V
to 5.1V. This pin is referred to the GND pin and should be
decoupled closely to the pin with a 47µF ceramic capacitor
(X7R, 1210 size, 10V Rating).
REF/DGC (Pin 8): When tied to REF, digital gain compres-
sion is disabled and the LTC2376-20 defines full-scale ac-
cording to the ±V_REF analog input range. When tied to GND,
digital gain compression is enabled and the LTC2376‑20
defines full-scale with inputs that swing between 10% and
90% of the ±V_REF analog input range.
CNV (Pin 9): Convert Input. A rising edge on this input
powers up the part and initiates a new conversion. Logic
levels are determined by OV_DD.
BUSY (Pin 11): BUSY Indicator. Goes high at the start of
a new conversion and returns low when the conversion
has finished. Logic levels are determined by OV_DD.
RDL/SDI (Pin 12): When CHAIN is low, the part is in nor-
mal mode and the pin is treated as a bus enabling input.
When CHAIN is high, the part is in chain mode and the
pin is treated as a serial data input pin where data from
another ADC in the daisy chain is input. Logic levels are
determined by OV_DD.
SCK (Pin 13): Serial Data Clock Input. When SDO is enabled,
the conversion result or daisy-chain data from another
ADC is shifted out on the rising edges of this clock MSB
first. Logic levels are determined by OV_DD.
SDO (Pin 14): Serial Data Output. The conversion result or
daisy-chain data is output on this pin on each rising edge
of SCK MSB first. The output data is in 2’s complement
format. Logic levels are determined by OV_DD.
OV_DD (Pin 15): I/O Interface Digital Power. The range of
OV_DD is 1.71V to 5.25V. This supply is nominally set to
the same supply as the host interface (1.8V, 2.5V, 3.3V,
or 5V). Bypass OV_DD to GND with a 0.1µF capacitor.
GND (Exposed Pad Pin 17 – DFN Package Only): Ground.
Exposed pad must be soldered directly to the ground plane.
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For more information www.linear.com/LTC2376-20