Linear Technology LTC2378-20, 20-Bit, 1Msps, SAR ADC with 104dB SNR. Req DC590 or DC890 DC1925A-A DC1925A-A 数据表
产品代码
DC1925A-A
LTC2378-20
1
237820f
Typical applicaTion
FeaTures
DescripTion
20-Bit, 1Msps, Low Power
SAR ADC with 0.5ppm INL
is a low noise, low power, high speed
20-bit successive approximation register (SAR) ADC.
Operating from a 2.5V supply, the LTC2378-20 has a
±V
REF
fully differential input range with V
REF
ranging from
2.5V to 5.1V. The LTC2378-20 consumes only 21mW and
achieves ±2ppm INL maximum, no missing codes at 20
bits with 104dB SNR.
The LTC2378-20 has a high speed SPI-compatible serial
The LTC2378-20 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
throughput with no cycle latency makes the LTC2378-20
ideally suited for a wide variety of high speed applications.
An internal oscillator sets the conversion time, easing exter-
nal timing considerations. The LTC2378-20 automatically
powers down between conversions, leading to reduced
power dissipation that scales with the sampling rate.
The LTC2378-20 features a unique digital gain compres-
The LTC2378-20 features a unique digital gain compres-
sion (DGC) function, which eliminates the driver amplifier’s
negative supply while preserving the full resolution of the
ADC. When enabled, the ADC performs a digital scaling
function that maps zero-scale code from 0V to 0.1 • V
REF
and full-scale code from V
REF
to 0.9 • V
REF
. For a typical
reference voltage of 5V, the full-scale input range is now
0.5V to 4.5V, which provides adequate headroom for
powering the driving amplifier from a single 5.5V supply.
Integral Nonlinearity vs Output Code
applicaTions
n
1Msps Throughput Rate
n
±0.5ppm INL (Typ)
n
Guaranteed 20-Bit No Missing Codes
n
Low Power: 21mW at 1Msps, 21µW at 1ksps
n
104dB SNR (Typ) at f
IN
= 2kHz
n
–125dB THD (Typ) at f
IN
= 2kHz
n
Digital Gain Compression (DGC)
n
Guaranteed Operation to 85°C
n
2.5V Supply
n
Fully Differential Input Range ±V
REF
n
V
REF
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
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
OUTPUT CODE
0
262144
524288
786432
1048576
–2.0
INL ERROR (ppm)
0.5
1.0
1.5
0
–0.5
–1.0
–1.5
2.0
237820 TA02
10Ω
V
REF
0V
V
REF
0V
10Ω
3300pF
6800pF
6800pF
–
+
V
REF
SAMPLE CLOCK
237820 TA01
10µF
0.1µF
2.5V
REF
1.8V TO 5V
2.5V TO 5.1V
47µF
(X7R, 1210 SIZE)
REF
GND
CHAIN
RDL/SDI
SDO
SCK
BUSY
CNV
REF/DGC
LTC2378-20
V
DD
OV
DD
IN
+
IN
–
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. Patents Pending. Protected by U.S. Patents, including
7705765, 7961132, 8319673.