MAX1240BESA+T

Analog To Digital Converters (ADC) Overview

The MAX1240BESA+T is a single-channel, 12-bit successive-approximation analog-to-digital converter (ADC) manufactured by Analog Devices Inc. under the Maxim Integrated brand. It operates on a single +2.7V to +3.6V supply and features an internal 2.5V reference voltage. The device supports a maximum sampling rate of 73 kS/s with a throughput clock frequency up to 2.1MHz. It utilizes a 3-wire serial interface compatible with SPI, QSPI, and MICROWIRE protocols. Key electrical specifications include a signal-to-noise ratio of 70 dB, differential nonlinearity of ±1 LSB, and integral nonlinearity of ±0.5 LSB. The component is housed in an 8-pin SO package and functions within a temperature range of -40°C to +85°C.

Analog To Digital Converters (ADC) Feature Summary

• Integrates a 12-bit SAR ADC architecture with an internal track-and-hold circuit for efficient signal acquisition.
• Features a built-in 2.5V voltage reference that can be enabled or disabled via the SHDN pin to support external references.
• Provides low-power operation with a dedicated shutdown mode accessible through the SHDN input pin.
• Supports standard microcontroller communication through a flexible 3-wire serial interface.

Analog To Digital Converters (ADC) Applications

• Battery-powered systems requiring extended operational life
• Portable data logging equipment
• Isolated data acquisition modules
• Process control instrumentation

Analog To Digital Converters (ADC) Procurement Notes

Verify the specific suffix 'V+' indicates automotive qualification and lead-free compliance when sourcing this part number. Confirm the package type matches the required PCB footprint. Ensure the operating environment falls within the specified industrial temperature range. Cross-reference the datasheet revision to confirm pinout consistency. Validate supplier authenticity to prevent counterfeit components.

Analog To Digital Converters (ADC) Selection Notes

Select the MAX1240BESA+T when a single-ended input and internal reference are required. Compare against the MAX1241 if a wider supply voltage range up to 5.25V is necessary. Consider the power consumption at the target sampling rate. Evaluate the serial interface compatibility with the host microcontroller. Assess the need for automotive qualification versus commercial grade options.

Analog To Digital Converters (ADC) Part Context

This component belongs to the MAX1240/MAX1241 family of low-power, 12-bit serial ADCs. The MAX1240 variant distinguishes itself by including an internal 2.5V reference, whereas the MAX1241 requires an external reference source. Both share identical architectural features and performance characteristics. The family targets applications demanding small form factors and minimal power consumption.

Analog To Digital Converters (ADC) Replacement Considerations

The TSM1285BESA+ is documented as an alternate source for the MAX1285 and serves as a higher-speed upgrade path relative to the MAX1240 series. Verify pin compatibility and interface timing requirements before substitution. Check if the replacement meets the specific voltage and accuracy constraints of the design.

Analog To Digital Converters (ADC) FAQ

How is the internal reference voltage controlled?

The internal 2.5V reference is enabled by pulling the SHDN pin high. Leaving the SHDN pin open disables the internal reference, allowing the use of an external reference voltage at the REF pin.

What is the minimum acquisition time for the track-and-hold circuit?

The minimum acquisition time is 1.5µs. This duration ensures the internal hold capacitor charges sufficiently based on the source impedance and internal resistance.

How does the device indicate the end of conversion?

The DOUT pin transitions from high impedance to logic low during conversion and then goes high to signal the end of conversion (EOC). Data bits are shifted out on subsequent falling edges of the SCLK.