LTC2309 Datasheet, PDF (1/20 Pages) Linear Technology – 8-Channel, 12-Bit SAR ADC with I2C Interface

LTC2309
8-Channel, 12-Bit SAR ADC
with I²C Interface
FEATURES
n _{12-Bit Resolution}
n _{Low Power: 1.5mW at 1ksps, 35μW Sleep Mode}
n _{14ksps Throughput Rate}
n _{Low Noise: SNR = 73.4dB}
n _{Guaranteed No Missing Codes}
n _{Single 5V Supply}
n _{2-wire I}²_{C Compatible Serial Interface with Nine}
Addresses Plus One Global for Synchronization
n _{Fast Conversion Time: 1.3μs}
n _{Internal Reference}
n _{Internal 8-Channel Multiplexer}
n _{Internal Conversion Clock}
n _{Unipolar or Bipolar Input Ranges (Software Selectable)}
n _{24-Pin 4mm × 4mm QFN Package}
APPLICATIONS
n _{Industrial Process Control}
n _{Motor Control}
n _{Accelerometer Measurements}
n _{Battery-Operated Instruments}
n _{Isolated and/or Remote Data Acquisition}
n _{Power Supply Monitoring}
DESCRIPTION
The LTC^®2309 is a low noise, low power, 8-channel, 12-bit
successive approximation ADC with an I²C compatible
serial interface. This ADC includes an internal reference
and a fully differential sample-and-hold circuit to reduce
common mode noise. The LTC2309 operates from an
internal clock to achieve a fast 1.3μs conversion time.
The LTC2309 operates from a single 5V supply and
draws just 300μA at a throughput rate of 1ksps. The
ADC enters nap mode when not converting, reducing
the power dissipation.
The LTC2309 is available in a small 24-pin 4mm × 4mm
QFN package. The internal 2.5V reference and 8-channel
multiplexer further reduce PCB board space require-
ments.
The low power consumption and small size make the
LTC2309 ideal for battery-operated and portable applica-
tions, while the 2-wire I²C compatible serial interface makes
this ADC a good match for space-constrained systems.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
BLOCK DIAGRAM
10μF
0.1μF
5V
0.1μF
10μF
CH0
CH1
CH2
CH3
ANALOG INPUTS
0V TO 4.096V UNIPOLAR CH4
±2.048V BIPOLAR _CH5
CH6
CH7
COM
AV_DD
DV_DD
LTC2309
ANALOG
INPUT
MUX
+
12-BIT
–
SAR ADC
AD1
AD0
I²C
SCL
PORT
SDA
INTERNAL
2.5V REF
V_REF
2.2μF
GND
0.1μF
REFCOMP
10μF
2309 TA01
1.00
0.75
0.50
0.25
0
–0.25
–0.50
–0.75
–1.00
0
Integral Nonlinearity
vs Output Code
1024
2048
3072
OUTPUT CODE
4096
2309 G01
2309f
1