Analog Devices Inc./Maxim Integrated MAX1111CPE

Overview

MAX1111CPE from Maxim Integrated is a low-power, 8-bit, 4-channel analog-to-digital converter (ADC) with integrated track/hold, 2.048V internal reference, SPI/QSPI/MICROWIRE-compatible serial interface, and software-configurable unipolar/bipolar single-ended/differential input modes. It operates from a single +2.7V to +5.5V supply, consumes only 85µA at 50ksps, and targets portable data loggers and hand-held measurement devices.

For engineers reviewing the MAX1111CPE datasheet, MAX1111CPE pinout, MAX1111CPE application, or MAX1111CPE equivalent, key selection considerations include its 4-channel analog input flexibility, 85µA active current at 50ksps, 16-pin QSOP package, ±1 LSB total unadjusted error, and support for both internal and external reference configurations.

Technical Context

The MAX1111CPE uses successive-approximation (SAR) architecture with an internal track/hold circuit enabling up to 50ksps sampling. Conversion timing is governed by either the internal 400kHz clock or an external serial clock (50kHz–500kHz), with acquisition time as low as 1µs and aperture jitter under 50ps.

Its analog front-end supports software-selectable input configurations: 4 single-ended or 2 differential channels, with full-scale ranges determined by the 2.048V internal reference or an external 1V–VDD reference. The serial interface features CS-controlled three-state outputs, SSTRB end-of-conversion strobe, and compatibility with SPI (CPOL=0, CPHA=0), QSPI, and MICROWIRE protocols.

Key Specifications

Pinout & Package

The MAX1111CPE is housed in a 16-pin QSOP package (5.3mm × 10.2mm, 0.65mm pitch), rated for 0°C to +70°C operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit multichannel ADC applications.

Compared with ADS7822U and MCP3204-I/P, the MAX1111CPE uniquely combines integrated 2.048V reference, software-configurable bipolar/single-ended operation, and ultra-low 6µA power-down current-making it optimal for space- and energy-constrained portable instrumentation where design simplicity and supply flexibility matter.

Availability

MAX1111CPE is available at Aetrix Electronics and suitable for portable data logging, hand-held measurement devices, and medical instruments requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for MAX1111CPE 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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, medical, and portable applications.

The MAX1111CPE belongs to Maxim's low-power serial ADC product line, designed specifically for battery-operated and space-constrained systems needing precision digitization with minimal external components and flexible input configuration.

FAQ

What is the maximum sampling rate supported by the MAX1111CPE?

The MAX1111CPE supports up to 50ksps when using the internal clock or an external serial clock of 500kHz. At this rate, the device draws 85µA from a +2.7V to +5.5V supply. Conversion time is fixed at 25µs in internal clock mode or 10 SCLK cycles in external clock mode - both meeting the 50ksps requirement. Lower clock frequencies proportionally reduce throughput but maintain full 8-bit accuracy.

Does the MAX1111CPE require an external reference voltage?

No, the MAX1111CPE does not require an external reference voltage because it integrates a precision 2.048V internal reference with ±0.3% initial accuracy and ±50ppm/°C temperature coefficient. However, it also supports external references from 1V to VDD applied at the REFIN pin - useful when matching system-level reference standards or extending full-scale range beyond 2.048V.

How many analog input channels does the MAX1111CPE support, and how are they configured?

The MAX1111CPE supports four analog input channels (CH0–CH3). These can be used in either 4-channel single-ended mode (each referenced to COM) or 2-channel pseudo-differential mode (CH0/CH1 and CH2/CH3 pairs). Configuration is controlled via bits SGL/DIF and SEL0–SEL2 in the 8-bit control byte sent to DIN, allowing runtime reconfiguration without hardware changes.

What is the purpose of the SSTRB pin on the MAX1111CPE?

The SSTRB (Serial Strobe) pin on the MAX1111CPE provides a hardware end-of-conversion signal for interrupt-driven microcontroller operation. In internal clock mode, SSTRB goes low at conversion start and high upon completion (25µs pulse). In external clock mode, it pulses high for two SCLK periods just before the MSB appears on DOUT. This eliminates polling overhead and enables deterministic timing in real-time systems.

Can the MAX1111CPE operate from a 3.3V supply, and what are its logic-level tolerances?

Yes, the MAX1111CPE operates fully across +2.7V to +5.5V, including standard 3.3V supplies. Its digital inputs (CS, SCLK, DIN) are 5.5V-tolerant regardless of VDD - enabling direct connection to both 3.3V and 5V microcontrollers without level shifters. DOUT and SSTRB outputs swing rail-to-rail (0V to VDD) and drive 16mA sink / 0.5mA source loads, ensuring robust interface integrity.