LTC2368-18_15 Datasheet, PDF (1/24 Pages) Linear Technology – 18-Bit, 1Msps, Pseudo- Differential Unipolar SAR ADC with 97dB SNR

FEATURES
n _{1Msps Throughput Rate}
n _{±2.5LSB INL (Max)}
n _{Guaranteed 18-Bit No Missing Codes}
n _{Low Power: 13.5mW at 1Msps, 13.5µW at 1ksps}
n _{97dB SNR (Typ) at fIN = 2kHz}
n _{–120dB THD (Typ) at fIN = 2kHz}
n _{Guaranteed Operation to 125°C}
n _{2.5V Supply}
n _{Pseudo-Differential Unipolar Input Range: 0V to VREF}
n _{VREF Input Range from 2.5V to 5.1V}
n _{No Pipeline Delay, No Cycle Latency}
n _{1.8V to 5V I/O Voltages}
n _{SPI-Compatible Serial I/O with Daisy-Chain Mode}
n _{Internal Conversion Clock}
n _{16-Lead MSOP and 4mm × 3mm DFN Packages}
APPLICATIONS
n _{Medical Imaging}
n _{High Speed Data Acquisition}
n _{Portable or Compact Instrumentation}
n _{Industrial Process Control}
n _{Low Power Battery-Operated Instrumentation}
n _ATE
LTC2368-18
18-Bit, 1Msps, Pseudo-
Differential Unipolar SAR
ADC with 97dB SNR
DESCRIPTION
The LTC^®2368-18 is a low noise, low power, high speed
18-bit successive approximation register (SAR) ADC.
Operating from a 2.5V supply, the LTC2368-18 has a 0V
to V_REF pseudo-differential unipolar input range with V_REF
ranging from 2.5V to 5.1V. The LTC2368-18 consumes
only 13.5mW and achieves ±2.5LSB INL maximum, no
missing codes at 18 bits with 97dB SNR.
The LTC2368-18 has a high speed SPI-compatible serial
interface that supports 1.8V, 2.5V, 3.3V and 5V logic while
also featuring a daisy-chain mode. The fast 1Msps through-
put with no cycle latency makes the LTC2368-18 ideally
suited for a wide variety of high speed applications. An
internal oscillator sets the conversion time, easing external
timing considerations. The LTC2368-18 automatically pow-
ers down between conversions, leading to reduced power
dissipation that scales with the sampling rate.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
SoftSpan is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners. Protected by U.S. Patents, including 7705765.
TYPICAL APPLICATION
2.5V 1.8V TO 5V
V_REF
0V
+
LT^®6202
–
10µF
0.1µF
10Ω
V_DD
OV_DD
CHAIN
IN⁺
RDL/SDI
10nF
LTC2368-18
IN^–
SDO
SCK
BUSY
REF
GND
CNV
2.5V TO 5.1V
236818 TA01a
47µF
(X5R, 0805 SIZE)
SAMPLE CLOCK
32k Point FFT f_S = 1Msps, f_IN = 2kHz
0
SNR = 97.2dB
–20
THD = –120dB
SINAD = 97.1dB
–40
SFDR = 120dB
–60
–80
–100
–120
–140
–160
–180
0
100 200 300 400 500
FREQUENCY (kHz)
236818 TA01b
236818f
1