Analog Devices Inc./Maxim Integrated MAX159BEPA+

Overview

MAX159BEPA+ from Maxim Integrated is a 10-bit pseudo-differential successive-approximation ADC with single +2.7V to +5.25V supply operation, 108ksps sampling rate, ±0.5 LSB differential nonlinearity, and SPI/QSPI/MICROWIRE-compatible 3-wire serial interface. It features internal track/hold, automatic power-down (<0.2 µA), and 2.5 µs wake-up time-designed for precision signal acquisition in space-constrained, battery-powered instrumentation.

For engineers reviewing the MAX159BEPA+ datasheet, MAX159BEPA+ pinout, MAX159BEPA+ application, or MAX159BEPA+ equivalent, this page delivers verified electrical specs, package mapping to 8-pin Plastic DIP, functional pin roles, real-world use cases in isolated data acquisition and medical instruments, and two validated alternative parts with documented technical and application differences.

Technical Context

The MAX159BEPA+ implements a SAR architecture with integrated track/hold, accepting pseudo-differential inputs (CH+, CH−) where only CH+ is sampled while CH− must remain stable within ±0.5 LSB. Conversion timing is synchronized to either internal laser-trimmed oscillator (2 MHz ±20%) or external clock (100 kHz–2.17 MHz), with acquisition time t_ACQ = 2.5 µs and conversion time t_CONV = 7.4 µs at full rate.

Its analog input structure includes on-chip 16 pF hold capacitor and 9 kΩ input resistance, requiring ≤10 Ω reference output impedance and 0.1 µF REF bypass. The 3-wire serial interface outputs 16-bit frames (3 leading ones, CHID, 10-bit data MSB-first, 2 sub-LSBs) with DOUT transitioning on SCLK falling edge and high-impedance when CS/SHDN is high.

Key Specifications

Pinout & Package

MAX159BEPA+ is housed in an 8-pin Plastic DIP package (0.300" wide), RoHS-compliant, rated for –40°C to +85°C operating temperature.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 10-bit pseudo-differential ADC applications.

Compared with ADS7822U and MAX11100ETE+, the MAX159BEPA+ uniquely combines pseudo-differential input capability, integrated track/hold, ultra-low shutdown current, and 8-pin DIP packaging-making it irreplaceable in legacy-space-constrained, battery-operated systems requiring common-mode noise immunity without added support circuitry.

Availability

MAX159BEPA+ is available at Aetrix Electronics and suitable for battery-powered data loggers, isolated sensor interfaces, and portable medical instruments requiring stable component supply across extended production lifecycles.

Supply support for MAX159BEPA+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power management ICs for industrial, medical, and communications applications.

The MAX157/MAX159 family was engineered specifically for low-power, space-constrained data acquisition-delivering 10-bit accuracy with integrated T/H and serial interface in sub-0.2" packages.

FAQ

What is the maximum sampling rate supported by the MAX159BEPA+?

The MAX159BEPA+ supports a maximum sampling rate of 108 ksps, achieved using an external serial clock frequency of 2.17 MHz in external clock mode. At this rate, conversion time is 7.4 µs and acquisition time is 2.5 µs. Lower rates reduce supply current-e.g., 10 ksps draws only 100 µA at +3 V-making the MAX159BEPA+ adaptable to varying power and throughput requirements.

Does the MAX159BEPA+ require an external reference voltage?

Yes, the MAX159BEPA+ requires an external reference voltage applied to the REF pin. It accepts 0 V to (VDD + 50 mV), with optimal performance at 2.5 V. The device demands ≤10 Ω reference output impedance and 250 µA DC load current during conversion. A 0.1 µF ceramic capacitor must be placed directly at the REF pin to maintain stability and noise immunity-no internal reference is provided in the MAX159BEPA+.

How does the pseudo-differential input configuration work on the MAX159BEPA+?

The MAX159BEPA+ uses pins CH0 (CH+) and CH1 (CH−) to form a pseudo-differential pair: only CH+ is actively sampled, while CH− serves as a stable reference node that must remain within ±0.5 LSB of GND. To achieve this, a 0.1 µF capacitor is required between CH− and GND. This architecture rejects common-mode noise on CH− while preserving signal integrity on CH+, making the MAX159BEPA+ ideal for bridge-based sensors without true differential amplifier overhead.

What are the power consumption characteristics of the MAX159BEPA+ in shutdown mode?

In shutdown mode-activated by pulling CS/SHDN high-the MAX159BEPA+ draws less than 0.2 µA typical supply current at +3 V and –40°C to +85°C. Shutdown current remains below 5 µA across the full temperature and supply range. Wake-up time is 2.5 µs when the external reference is stable to within 1 LSB; if reference stabilization is slower, wake-up delay must be extended accordingly. This enables aggressive power cycling in intermittent-sampling applications.

Which serial interface standards is the MAX159BEPA+ compatible with?

The MAX159BEPA+ 3-wire serial interface is explicitly compatible with SPI, QSPI, and MICROWIRE standards. It operates with CPOL = 0 and CPHA = 0, outputs data on the SCLK falling edge, and expects sampling on the rising edge. The interface delivers a 16-bit frame (3 leading ones, CHID, 10-bit data MSB-first, 2 sub-LSBs) and supports clock frequencies from 100 kHz to 2.17 MHz in external mode-or any rate up to 5 MHz in internal clock mode-ensuring seamless integration with industry-standard microcontrollers.