LTC2344-18 Quad, 18-Bit, 400ksps/ch Differential SoftSpan ADC with Wide Input Common Mode Range FEATURES DESCRIPTION n 400ksps per Channel Throughput The LTC 2344-18 is an 18-bit, low noise 4-channel simul- n Four Simultaneous Sampling Channels taneous sampling successive approximation register (SAR) n ADC with differential, wide common mode range inputs. 4LSB INL (Maximum, 4.096V Range) n Operating from a 5V supply and using the internal reference Guaranteed 18-Bit, No Missing Codes TM n and buffer, each channel of this SoftSpan ADC can be Differential, Wide Common Mode Range Inputs n independently configured on a conversion-by-conversion Per-Channel SoftSpan Input Ranges: basis to accept 4.096V, 0V to 4.096V, 2.048V, or 0V to 4.096V, 0V to 4.096V, 2.048V, 0V to 2.048V 2.048V signals. Individual channels may also be disabled 5V, 0V to 5V, 2.5V, 0V to 2.5V to increase throughput on the remaining channels. n 95dB Single-Conversion SNR (Typical) n 114dB THD (Typical) at f = 2kHz IN The wide input common mode range and 102dB CMRR of n 102dB CMRR (Typical) at f = 200Hz IN the LTC2344-18 analog inputs allow the ADC to directly n Rail-to-Rail Input Overdrive Tolerance digitize a variety of signals, simplifying signal chain de- n Guaranteed Operation to 125C sign. This input signal flexibility, combined with 4LSB n Integrated Reference and Buffer (4.096V) INL, no missing codes at 18 bits, and 95dB SNR, makes n SPI CMOS (1.8V to 5V) and LVDS Serial I/O the LTC2344-18 an ideal choice for many applications n Internal Conversion Clock, No Cycle Latency requiring wide dynamic range. n 81mW Power Dissipation (Typical) The LTC2344-18 supports pin-selectable SPI CMOS (1.8V n 32-Lead (5mm 5mm) QFN Package to 5V) and LVDS serial interfaces. Between one and four lanes of data output may be employed in CMOS mode, APPLICATIONS allowing the user to optimize bus width and throughput. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n Programmable Logic Controllers SoftSpan is a trademark of Linear Technology Corporation. All other trademarks are the property n of their respective owners. Protected by U.S. Patents, including 7705765, 7961132, 8319673, Industrial Process Control 9197235. n Medical Imaging n High Speed Data Acquisition TYPICAL APPLICATION 5V 1.8V TO 5V Integral Nonlinearity vs 0.1F 2.2F 0.1F Output Code and Channel CMOS OR LVDS 2.0 I/O INTERFACE 4.096V RANGE FULLY + V V OV 1.5 FULLY DIFFERENTIAL DRIVE (IN = IN ) DD DDLBYP DD LVDS/CMOS + ARBITRARY DIFFERENTIAL IN0 ALL CHANNELS S/H PD 5V 5V IN0 1.0 LTC2344-18 0.5 SDO0 0V 0V S/H 0 18-BIT MUX SDO3 SAR ADC UNIPOLAR BIPOLAR 0.5 SCKO 5V 5V SCKI S/H 1.0 SDI CS 1.5 BUSY + 0V 0V SAMPLE IN3 CNV S/H CLOCK IN3 2.0 + REFBUF REFIN GND DIFFERENTIAL INPUTS IN /IN WITH 131072 65536 0 65536 131072 WIDE INPUT COMMON MODE RANGE 234418 TA01a OUTPUT CODE 47F 0.1F 234418 TA01b FOUR SIMULTANEOUS SAMPLING CHANNELS 234418f 1 For more information www.linear.com/LTC2344-18 INL ERROR (LSB)LTC2344-18 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Notes 1, 2) TOP VIEW Supply Voltage (V ) ..................................................6V DD Supply Voltage (OV ) ................................................6V DD Internal Regulated Supply Bypass (V ) ... (Note 3) DDLBYP 32 31 30 29 28 27 26 25 Analog Input Voltage + + + IN3 1 24 SDO /SDO3 IN0 to IN3 , + IN3 2 23 SCKO /SDO2 IN0 to IN3 (Note 4) .................. 0.3V to (V + 0.3V) DD + IN2 3 22 SCKO /SCKO REFIN .................................................... 0.3V to 2.8V + IN2 OV 4 21 DD 33 REFBUF, CNV (Note 4) ............. 0.3V to (V + 0.3V) GND DD IN1 5 20 GND + Digital Input Voltage (Note 4) ..... 0.3V to (OV + 0.3V) IN1 6 19 SCKI /SCKI DD + IN0 7 18 SCKI /SDO1 Digital Output Voltage (Note 4) .. 0.3V to (OV + 0.3V) DD + IN0 8 17 SDI /SDO0 Power Dissipation .............................................. 500mW 9 10 11 12 13 14 15 16 Operating Temperature Range LTC2344C ................................................ 0C to 70C LTC2344I .............................................40C to 85C LTC2344H .......................................... 40C to 125C UH PACKAGE 32-LEAD (5mm 5mm) PLASTIC QFN Storage Temperature Range .................. 65C to 150C T = 150C, = 44C/W JMAX JA EXPOSED PAD (PIN 33) IS GND, MUST BE SOLDERED TO PCB