LTC1400IS8#PBF

Analog To Digital Converters (ADC) Overview

The LTC1400IS8#PBF is a complete 12-bit, 400ksps successive approximation register (SAR) analog-to-digital converter in an 8-lead SOIC package. It operates from a single 5V supply or ±5V supplies, consuming 75mW at full speed. Key electrical parameters include ±1LSB INL and DNL, a 2.42V internal reference, and a 3-wire serial interface compatible with SPI and MICROWIRE. The device features two power-saving modes: Nap mode (6mW) with instant wake-up and Sleep mode (30μW typical). It supports unipolar (0V to 4.096V) and bipolar (±2.048V) input ranges.

Analog To Digital Converters (ADC) Feature Summary

• Complete 12-bit ADC with 400ksps sampling rate and 75mW power dissipation
• Integrated 2.42V precision reference with external overdrive capability
• Dual power-saving modes: Nap (6mW) and Sleep (30μW)
• 3-wire serial interface compatible with DSPs and microprocessors

Analog To Digital Converters (ADC) Applications

• High-speed data acquisition systems
• Digital signal processing applications
• Multiplexed data acquisition systems
• Audio and telecom processing
• Low power and battery-operated systems

Analog To Digital Converters (ADC) Procurement Notes

Verify the IS8 suffix indicates the industrial temperature range (-40°C to +85°C) and SOIC-8 package. Confirm #PBF denotes lead-free compliance. Check current availability as distribution status may vary. Ensure board layout separates digital and analog grounds to maintain specified linearity and dynamic performance.

Analog To Digital Converters (ADC) Selection Notes

Select this component for applications requiring high-speed 12-bit conversion in a compact SO-8 footprint. Choose unipolar operation for single-supply designs (0V to 4.096V input) or bipolar operation for dual-supply designs (±2.048V input). Consider Nap mode for frequent active periods and Sleep mode for extended idle times to minimize power consumption.

Analog To Digital Converters (ADC) Part Context

The LTC1400 series includes commercial (C) and industrial (I) temperature variants. The IS8 variant specifically covers -40°C to +85°C. Other family members like the LTC1286 offer differential inputs and lower speeds, while the LTC1864 provides 16-bit resolution. The LTC1400 is distinguished by its integrated reference and high-speed SAR architecture in an 8-pin package.

Analog To Digital Converters (ADC) Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Designers should verify pin compatibility and electrical specifications when considering alternative SAR ADCs from other manufacturers.

Analog To Digital Converters (ADC) FAQ

How does the LTC1400 determine if it is operating in unipolar or bipolar mode?

The LTC1400 has a built-in detection circuit that automatically switches to bipolar mode if the VSS potential is forced below GND. For unipolar operation, VSS should be tied to GND.

What is the wake-up time from Sleep mode?

Upon waking from Sleep mode, the device requires approximately 4ms for the internal reference to settle. A REFREADY bit in the serial data word indicates when the reference is stable and the chip is ready to convert.

Can the internal reference be driven externally?

Yes, the VREF pin can be driven externally to adjust the input span. The external voltage must be at least 2.45V to prevent conflict with the internal reference and should not exceed 5V.