LTC2309_15 Datasheet, PDF (1/26 Pages) Linear Technology – 8-Channel, 12-Bit SAR ADC with IC 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 _{Guaranteed Operation from –40°C to 125°C}
(TSSOP Package)
n _{24-Pin 4mm × 4mm QFN and 20-Pin TSSOP Packages}
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 both a small 24-pin 4mm ×
4mm QFN and a 20-pin TSSOP package. The internal 2.5V
reference and 8-channel multiplexer further reduce PCB
board space requirements.
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, LTM, Linear Technology and the Linear logo are registered trademarks and
Easy Drive is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
BLOCK DIAGRAM
5V
0.1µF
10µF
CH0
CH1
CH2
CH3
ANALOG INPUTS
0V TO 4.096V UNIPOLAR CH4
±2.048V BIPOLAR _CH5
CH6
CH7
COM
ANALOG
INPUT
MUX
V_DD
LTC2309
+
12-BIT
–
SAR ADC
I²C
PORT
INTERNAL
2.5V REF
AD1
AD0
SCL
SDA
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
2309fd