LTC2440 Datasheet | Linear Technology

LTC2440 24-Bit High Speed Differential ∆∑ ADC with Selectable Speed/Resolution Features n Up to 3.5k Hz Output Rate (External f O) n Selectable Speed/Resolution n 2µVRMS Noise at 880Hz Output Rate n 200n VRMS Noise at 6.9Hz Output Rate with Simultaneous 50/60Hz Rejection n 0.0005% INL, No Missing Codes n Autosleep Enables 20µA Operation at 6.9Hz n <5µV Offset (4.5V < VCC < 5.5V, - 40°C to 85°C) n Differential Input and Differential Reference with GND to VCC mon Mode Range n No Latency, Each Conversion is Accurate Even After an Input Step n Internal Oscillator- No External ponents n Pin patible with the LTC2410 n 24-Bit ADC in Narrow 16-Lead SSOP Package APPLICATIONS n High Speed Multiplexing n Weight Scales n Auto Ranging 6-Digit DVMs n Direct Temperature Measurement n High Speed Data Acquisition DESCRIPTION The LTC®2440 is a high speed 24-bit No Latency ∆∑TM ADC with 5ppm INL and 5µV offset. It uses a proprietary delta-sigma architecture enabling variable speed and resolution with no latency. Ten speed/resolution binations (6.9Hz/200n VRMS to 3.5k Hz/25µVRMS) are programmed through a simple serial interface. Alternatively, by tying a single pin HIGH or LOW, a fast (880Hz/2µVRMS) or ultralow noise (6.9Hz, 200n VRMS, 50/60Hz rejection) speed/resolution bination can be easily selected. The accuracy (offset, full-scale, linearity, drift) and power dissipation are independent of the speed selected. Since there is no latency, a speed/resolution change may be made between conversions with no degradation in performance. Following each conversion cycle, the LTC2440 automatically enters a low power sleep state. Power dissipation may be reduced by increasing the duration of this sleep state. For example, running at the 3.5k Hz conversion speed but reading data at a 100Hz rate draws 240µA average current (1.1m W) while reading data at a 7Hz output rate draws only 25µA (125µW).The LTC2440 municates through a flexible 3-wire or 4-wire digital...