Features

• 2x Speed Up Version of the LTC2430: 15Hz Output Rate, 60Hz Notch—LTC2435; 13.75Hz Output Rate, Simultaneous 50Hz/60Hz Notch-LTC2435-1
• Differential Input and Differential Reference with GND to V_CC Common Mode Range
• 3ppm INL, No Missing Codes
• 10ppm Gain Error
• 0.8ppm Noise
• Single Conversion Settling Time for Multiplexed Applications
• Internal Oscillator—No External Components Required
• 20-Bit ADC in Narrow SSOP-16 Package
  (SO-8 Footprint)
• Single Supply 2.7V to 5.5V Operation
• Low Supply Current (200µA,4µA in Auto Sleep)

Typical Application

Description

The LTC®2435/2435-1 are 2.7V to 5.5V micropower 20-bit differential Delta Sigma analog to digital converters with integrated oscillator, 3ppm INL and 0.8ppm RMS noise. They use delta-sigma technology and provide single cycle settling time for multiplexed applications. Through a single pin, the LTC2435 can be configured for better than 110dB input differential mode rejection at 50Hz or 60Hz ±2%, or it can be driven by an external oscillator for a user defined rejection frequency. The LTC2435-1 can be configured for better than 87dB input differential mode rejection over the range of 49Hz to 61.2Hz (50Hz and 60Hz ±2% simultaneously). The internal oscillator requires no external frequency setting components.

The converters accept any external differential reference voltage from 0.1V to V_CC for flexible ratiometric and remote sensing measurement configurations. The fullscale differential input range is from –0.5V_REF to 0.5V_REF. The reference common mode voltage, V_REFCM, and the input common mode voltage, V_INCM, may be independently set anywhere within the GND to V_CC range of the LTC2435/LTC2435-1. The DC common mode input rejection is better than 120dB.

The LTC2435/LTC2435-1 communicate through a flexible 3-wire digital interface which is compatible with SPI and MICROWIRE™ protocols.