Analog Devices Inc./Maxim Integrated MAX1085BCSA+

Overview

MAX1085BCSA+ from Maxim Integrated is a 10-bit, 300ksps serial analog-to-digital converter (ADC) operating from a single +2.7V to +3.6V supply, featuring an internal +2.5V reference, integrated track/hold, and SPI/QSPI/MICROWIRE-compatible 3-wire interface. It delivers ±0.5 LSB INL, 60dB SINAD, and 2.5mA supply current at full speed-optimized for battery-powered instrumentation and portable data acquisition.

For engineers reviewing the MAX1085BCSA+ datasheet, MAX1085BCSA+ pinout, MAX1085BCSA+ application, or MAX1085BCSA+ equivalent, this page provides verified electrical specs, thermal performance across –40°C to +85°C, timing constraints for 4.8MHz SCLK operation, and real-world design guidance for remote sensor interfaces with low-power, space-constrained layouts.

Technical Context

The MAX1085BCSA+ employs a successive-approximation register (SAR) architecture with an internal capacitive DAC and track/hold circuitry, acquiring analog inputs in ≤625ns and completing conversion in 3.3µs using a 4.8MHz external serial clock. Its unipolar transfer function maps 0V–2.5V input range to 10-bit digital output (0x000–0x3FF), with MSB-first serial output synchronized to SCLK rising edges.

It operates in two modes: normal (active conversion, 2.5mA IDD) and shutdown (2µA ISHDN), with REF output disabled during shutdown. The internal 2.5V reference exhibits ±15ppm/°C tempco and supports up to 800µA external load when bypassed with 4.7µF.

Key Specifications

Pinout & Package

MAX1085BCSA+ is housed in an 8-pin SO (Small Outline) package, RoHS-compliant and lead(Pb)-free. Pin assignments are validated per Maxim's functional diagram and pin description table.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX1085BCSA+, ADS7822U trades internal reference and speed for broader supply tolerance, while MAX11100ETE+ offers higher resolution and throughput in a non-pin-compatible 16-pin package-neither serves as a drop-in replacement, but both address adjacent 10–12-bit serial ADC use cases.

Availability

MAX1085BCSA+ is available at Aetrix Electronics and suitable for portable data logging, battery-powered instrumentation, and medical device designs requiring stable component supply with guaranteed long-term manufacturability.

Supply support for MAX1085BCSA+ 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 communications applications.

The MAX1085 belongs to Maxim's precision data-acquisition ADC family, designed specifically for low-power, space-constrained systems requiring integrated reference and simple serial interfacing-targeting portable and remote sensing applications.

FAQ

What is the operating temperature range for MAX1085BCSA+?

The MAX1085BCSA+ is rated for operation from –40°C to +85°C. This extended industrial temperature range is confirmed in the Ordering Information table and validated across all key specifications-including INL (±0.5 LSB), DNL (±1.0 LSB), and supply current (2.5mA typical at 300ksps)-ensuring reliable performance in harsh environments such as field-deployed sensors or industrial controllers.

Does MAX1085BCSA+ include an internal voltage reference?

Yes, MAX1085BCSA+ integrates a factory-trimmed +2.5V reference with ±2mV initial accuracy and ±15ppm/°C temperature coefficient. The REF pin delivers this voltage and must be bypassed with a 4.7µF capacitor to ensure stability and meet specified AC performance; the internal reference is automatically disabled when SHDN is asserted.

What is the maximum serial clock frequency supported by MAX1085BCSA+?

MAX1085BCSA+ supports a maximum SCLK frequency of 4.8MHz, as specified in the ELECTRICAL CHARACTERISTICS-MAX1085 section. At this clock rate, the device achieves its full 300ksps sampling rate with 16 clock cycles per conversion; timing parameters including tCL (83ns min), tCH (83ns min), and tCP (208ns min) are guaranteed across the –40°C to +85°C range.

How does shutdown mode affect power consumption and wake-up time in MAX1085BCSA+?

In shutdown mode (SHDN = low), MAX1085BCSA+ draws only 2µA typical supply current. Wake-up time depends on the 4.7µF capacitor at REF: after exiting shutdown, up to 1.4ms may be required for the internal reference to stabilize before accurate conversions can begin-this delay increases with longer shutdown durations due to capacitor discharge.

Is MAX1085BCSA+ pin-compatible with other devices in the MAX1084/MAX1085 family?

Yes, MAX1085BCSA+ shares identical 8-pin SO package and pinout with all MAX1084/MAX1085 variants (e.g., MAX1085ACSA+, MAX1084BCSA+). This allows direct substitution within the same temperature grade and resolution grade-though supply voltage (2.7–3.6V vs. 4.5–5.5V) and sampling rate (300ksps vs. 400ksps) differ between MAX1085 and MAX1084 series.