Analog Devices Inc./Maxim Integrated MAX11111ATB+

Overview

MAX11111ATB+ from Maxim Integrated is a 8-bit, dual-channel, single-ended successive approximation analog-to-digital converter (ADC) with 3Msps throughput, 73dB SNR (typ), and external reference input. It operates from 2.2V to 3.6V supply, consumes 5.2mW at full speed, and features SPI-/QSPI-/MICROWIRE-compatible 3-wire serial interface - ideal for space-constrained, battery-powered data acquisition systems requiring high-speed sampling and low power.

For engineers reviewing the MAX11111ATB+ datasheet, MAX11111ATB+ pinout, MAX11111ATB+ application, or MAX11111ATB+ equivalent, key selection considerations include its 3Msps conversion rate with no pipeline delay, dual analog inputs with channel-to-channel gain matching of ±0.01 LSB, external reference support up to VDD + 0.05V, 1.3µA power-down current, and compatibility with 1.5V–3.6V I/O voltage domains.

Technical Context

The MAX11111ATB+ implements a true successive approximation register (SAR) architecture with integrated sample-and-hold, delivering 3Msps throughput without pipeline latency. Its dual-input 2:1 MUX enables interleaved or independent sampling of two analog signals, while dedicated REF and OVDD pins decouple reference and digital interface supplies for improved noise immunity.

Timing is tightly controlled via CS-synchronized serial interface: aperture jitter is 15ps, acquisition time is 52ns, and conversion completes in 260ns. The device supports variable I/O voltage (1.5V–3.6V) on OVDD, allowing direct interfacing with mixed-voltage digital systems without level shifters.

Key Specifications

Pinout & Package

MAX11111ATB+ is housed in a 10-pin, 3mm × 3mm TDFN-EP package with exposed pad for thermal enhancement and ground connection. Pin numbering follows standard TDFN top-view convention (pin 1 marked).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar ADC applications.

Compared with ADS7822IDR and AD7476ARTZ-REEL7, the MAX11111ATB+ uniquely combines dual-channel sampling, external reference support, and 3Msps throughput in a 3mm × 3mm package - making it optimal for compact, high-dynamic-range, battery-sensitive dual-sensor systems where timing determinism and supply flexibility are critical.

Availability

MAX11111ATB+ is available at Aetrix Electronics and suitable for portable data logging, medical instrumentation, battery-operated systems, industrial sensor interfaces, and communication subsystems requiring stable component supply, RoHS-compliant packaging, and guaranteed long-term availability.

Supply support for MAX11111ATB+ 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 demanding industrial, medical, and automotive applications.

The MAX111xx family targets ultra-low-power, high-speed data acquisition in space-constrained portable and embedded systems - emphasizing small footprint, flexible I/O voltage, and robust performance across extended temperature ranges.

FAQ

What is the maximum serial clock frequency supported by MAX11111ATB+?

The MAX11111ATB+ supports a maximum serial clock (SCLK) frequency of 48MHz, enabling full 3Msps throughput with minimal interface overhead. This specification is guaranteed over the full −40°C to +125°C operating range and allows direct connection to high-speed microcontrollers without clock division. The MAX11111ATB+ maintains timing compliance at this rate with t5/t6 pulse width requirements of 40–60% duty cycle.

Does MAX11111ATB+ require an external reference voltage to operate?

No - the MAX11111ATB+ can operate using VDD as the reference when the REF pin is tied to VDD, but it also supports external reference voltages from 1V to VDD + 0.05V. Using an external reference improves absolute accuracy and temperature stability, especially in systems where VDD has significant ripple or drift. The MAX11111ATB+'s REF input leakage is only 0.005µA (typ), minimizing loading on precision references.

How does the CHSEL pin function in MAX11111ATB+?

The CHSEL pin on the MAX11111ATB+ selects between the two analog inputs: CHSEL = low connects AIN1 to the ADC core, and CHSEL = high connects AIN2. This hardware-selectable MUX allows deterministic channel switching without serial command overhead, enabling synchronized dual-channel sampling or rapid alternation. The MAX11111ATB+ maintains identical INL, DNL, and SNR performance on both channels, with channel-to-channel gain matching of ±0.01 LSB.

What is the power consumption of MAX11111ATB+ during conversion and in power-down mode?

The MAX11111ATB+ consumes 5.2mW (1.6mA at 3.3V) during full-speed 3Msps operation, and drops to just 1.3µA (4.3µW at 3.3V) in power-down mode. Power-down is entered by holding CS high for >100ns, and wake-up requires only one full conversion cycle - less than 334ns. This ultra-low quiescent current makes the MAX11111ATB+ ideal for duty-cycled sensor nodes where average power must remain below 10µW.

Is MAX11111ATB+ compatible with standard SPI interfaces?

Yes - the MAX11111ATB+ features a 3-wire SPI-compatible serial interface (CS, SCLK, DOUT) with no requirement for SDI or MOSI lines, as it is read-only. It supports standard SPI modes 0 and 3 (CPOL = 0/1, CPHA = 0), and interoperates natively with QSPI and MICROWIRE controllers without external logic. The DOUT pin goes high-impedance when CS is high, enabling multiple MAX11111ATB+ devices on a shared bus with individual chip select lines.