LTC2379-18

1

237918f

TYPICAL APPLICATION

FEATURES

DESCRIPTION

18-Bit, 1.6Msps, Low Power

SAR ADC with 101.2dB SNR

18-bit successive approximation register (SAR) ADC. Op-

5.1V.TheLTC2379-18consumesonly18mWandachieves

±2LSB INL maximum, no missing codes at 18-bits with

101.2dB SNR.

The LTC2379-18 has a high speed SPI-compatible se-

rial interface that supports 1.8V, 2.5V, 3.3V and 5V logic

while also featuring a daisychain mode. The fast 1.6Msps

throughput with no cycle latency makes the LTC2379-18

ideally suited for a wide variety of high speed applications.

Aninternaloscillatorsetstheconversiontime,easingexter-

nal timing considerations. The LTC2379-18 automatically

powers down between conversions, leading to reduced

power dissipation that scales with the sampling rate.

The LTC2379-18 features a unique digital gain compres-

sion(DGC)function,whicheliminatesthedriveramplifier’s

negative supply while preserving the full resolution of the

ADC. When enabled, the ADC performs a digital scaling

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.

APPLICATIONS

n

1.6Msps Throughput Rate

n

±2LSB INL (Max)

n

Guaranteed 18-Bit No Missing Codes

n

Low Power: 18mW at 1.6Msps, 18µW at 1.6ksps

n

n

n

Digital Gain Compression (DGC)

n

Guaranteed Operation to 125°C

n

2.5V Supply

n

n

n

No Pipeline Delay, No Cycle Latency

n

1.8V to 5V I/O Voltages

n

SPI-Compatible Serial I/O with Daisychain Mode

n

Internal Conversion Clock

n

16-pin 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

FREQUENCY (kHz)

0

100 200 300 400

800

700

600

500

–180

–60

–40

–20

–80

–100

–120

–140

–160

0

237918 TA02

SNR = 101.2dB

THD = –120dB

SINAD = 101.1dB

SFDR = 121dB

20

0V

0V

20

3300pF

3300pF

3300pF

–

+

SAMPLE CLOCK

237918 TA01

10µF

0.1µF

2.5V

REF

1.8V TO 5V

2.5V TO 5.1V

47µF

(X5R, 0805 SIZE)

REF

GND

CHAIN

RDL/SDI

SDO

SCK

BUSY

CNV

REF/DGC

LTC2379-18

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.