Datasheet LTC2435, LTC2435-1 (Analog Devices)

LTC2435/LTC2435-1 20-Bit No Latency ∆∑™ ADCs with Differential Input and Differential Reference
FeaTures DescripTion
n
2
×
Speed Up Version of the LTC2430: 15Hz Output
The LTC®2435/LTC2435-1 are 2.7V to 5.5V micropower
Rate, 60Hz Notch—LTC2435; 13.75Hz Output Rate,
20-bit differential ∆∑ analog to digital converters with
Simultaneous 50Hz/60Hz Notch—LTC2435-1
integrated oscillator, 3ppm INL and 0.8ppm RMS noise. n
Differential Input and Differential Reference with
They use delta-sigma technology and provide single
GND to VCC Common Mode Range
cycle settling time for multiplexed applications. Through n
3ppm INL, No Missing Codes
a single pin, the LTC2435 can be configured for better n
10ppm Gain Error
than 110dB input differential mode rejection at 50Hz or n
0.8ppm Noise
60Hz ±2%, or it can be driven by an external oscillator n
Single Conversion Settling Time for Multiplexed
for a user defined rejection frequency. The LTC2435-1
Applications
can be configured for better than 87dB input differential n Internal Oscillator—No External Components Required mode rejection over the range of 49Hz to 61.2Hz (50Hz n and 60Hz ±2% simultaneously). The internal oscillator Single Supply 2.7V to 5.5V Operation n Low Supply Current (200µA,4µA in Auto Sleep) requires no external frequency setting components. n 20-Bit ADC in Narrow SSOP-16 Package The converters accept any external differential reference (SO-8 Footprint) voltage from 0.1V to VCC for flexible ratiometric and re-
applicaTions
mote sensing measurement configurations. The full-scale differential input range is from –0.5VREF to 0.5VREF . The n Direct Sensor Digitizer reference common mode voltage, VREFCM, and the input n Weight Scales common mode voltage, VINCM, may be independently set n Direct Temperature Measurement anywhere within the GND to VCC range of the LTC2435/ n Gas Analyzers LTC2435-1. The DC common mode input rejection is n Strain Gage Transducers better than 120dB. n Instrumentation The LTC2435/LTC2435-1 communicate through a flexible n Data Acquisition 3-wire digital interface which is compatible with SPI and n Industrial Process Control MICROWIRE™ protocols. n 6-Digit DVMs L, LT, LTC and LTM are registered trademarks and C-Load and No Latency ∆∑ are trademarks of Linear Technology Corporation. Protected by U.S. Patents including 6140950, 6169506.
Typical applicaTions Integral Nonlinearity vs Input
10 2.7V TO 5.5V 8 1μF VCC= INTERNAL OSC/50Hz REJECTION (LTC2435) 2 14 6 V = EXTERNAL CLOCK SOURCE CC FO = INTERNAL OSC/60Hz REJECTION (LTC2435) 4 LTC2435/ = INTERNAL 50Hz/60Hz REJECTION (LTC2435-1) LTC2435-1 REF 2 TA = 25°C 3 T REFERENCE A = 85°C REF+ 13 SCK 0 VOLTAGE 4 0.1V TO V REF– –2 CC T 3-WIRE A = –45°C 5 12 INL (ppm OF V –4 ANALOG INPUT RANGE IN+ SDO SPI INTERFACE F –0.5V O = GND REF TO 0.5VREF 6 –6 IN– 11 V CS CC = 5V 1, 7, 8, 9, 10, 15, 16 –8 VREF = 5V GND V 2435 TA01 INCM = VINCM = 2.5V –10–2.5 –1.5 –0.5 0.5 1.5 2.5 INPUT VOLTAGE (V) 2435 TA01b 24351fc For more information www.linear.com/LTC2435 1 Document Outline Features Description Applications Typical Applications Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Converter Characteristics Analog Input And Reference Digital Inputs And Digital Outputs Power Requirements Timing Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Test Circuits Applications Information Package Description Revision History Typical Application Related Parts