Analog Devices Inc./Maxim Integrated MAX1245BCPP

Overview

MAX1245BCPP from Maxim Integrated is a 12-bit, 8-channel serial analog-to-digital converter with integrated track/hold, SPI/QSPI/MICROWIRE-compatible 4-wire interface, ±1 LSB integral nonlinearity, and single +2.375V to +3.3V supply operation. It supports software-configurable unipolar/bipolar and single-ended/differential inputs, and delivers 100ksps conversion rate with 0.8mA active current - ideal for portable data loggers requiring low-power, high-accuracy signal digitization.

For engineers reviewing the MAX1245BCPP datasheet, MAX1245BCPP pinout, MAX1245BCPP application, or MAX1245BCPP equivalent, key selection considerations include its 20-pin DIP package, 1µA power-down current, internal/external clock flexibility, 100kHz sampling rate track/hold, and compatibility with TMS320-family DSPs via SSTRB strobe output.

Technical Context

The MAX1245BCPP employs successive-approximation architecture with a capacitive DAC and internal track/hold circuitry, enabling precise 12-bit conversions without external hold capacitors. Its pseudo-differential input structure supports eight single-ended or four differential channel pairs (CH0/CH1 through CH6/CH7), with COM pin serving as stable reference for zero-code alignment.

Conversion timing is governed by either internal clock (1.5MHz or 225kHz, selectable via SHDN pin state) or external serial clock (up to 1.5MHz); acquisition time is fixed at 2.0µs minimum, and conversion completes in ≤7.5µs (internal mode) or 120µs (external mode). The device uses a programmable 8-bit control byte to configure channel, polarity, input mode, and clock/power-down settings.

Key Specifications

Pinout & Package

The MAX1245BCPP is housed in a 20-pin plastic DIP package (0.300" wide), RoHS-compliant and compatible with standard through-hole PCB assembly processes.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit serial ADC applications.

Compared with MAX1245ACPP, the MAX1245BCPP trades 0.5 LSB INL tolerance for broader production availability and lower unit cost, while retaining identical power, timing, and interface behavior. Against ADS7822U, MAX1245BCPP provides integrated multiplexing, hardware strobe, and superior noise immunity at the expense of package size and maximum throughput.

Availability

MAX1245BCPP is available at Aetrix Electronics and suitable for portable data logging, medical instrumentation, and battery-powered test equipment requiring stable component supply across long-lifecycle industrial programs.

Supply support for MAX1245BCPP 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 markets.

The MAX1245 series was designed specifically for low-power, multi-channel data acquisition in portable and battery-operated systems - emphasizing single-supply operation, integrated track/hold, and minimal external component count.

FAQ

What is the maximum sampling rate supported by the MAX1245BCPP?

The MAX1245BCPP achieves a maximum sampling rate of 100ksps under typical conditions (fCLK = 1.5MHz, external clock mode). In internal clock mode, conversion time is ≤7.5µs, allowing up to ~133ksps theoretical throughput, though system-level timing constraints and acquisition time (2.0µs minimum) limit practical sustained rate to 100ksps. The MAX1245BCPP datasheet specifies 100ksps as the guaranteed maximum conversion rate across temperature and voltage ranges.

Does the MAX1245BCPP require an external reference voltage?

Yes, the MAX1245BCPP requires an external reference voltage applied to the VREF pin. It does not include an internal reference. The device accepts 0V to VDD (typically +2.048V) at VREF, with specified input current of 82–120µA and input resistance of 18kΩ. Using a stable, low-noise external reference such as the MAX6126 is recommended to maintain ±1 LSB INL performance in the MAX1245BCPP.

How does the SHDN pin function on the MAX1245BCPP?

The SHDN pin on the MAX1245BCPP is a three-level control: pulling it low enables hardware shutdown (IQ ≤10µA); leaving it open configures the internal clock to 1.5MHz; pulling it high sets the internal clock to 225kHz. This eliminates the need for external logic to manage power states. The MAX1245BCPP also supports software-selectable power-down via PD bits in the control byte, allowing dynamic control independent of SHDN state.

Can the MAX1245BCPP perform differential measurements?

Yes, the MAX1245BCPP supports true differential measurements using four predefined channel pairs: CH0/CH1, CH2/CH3, CH4/CH5, and CH6/CH7. This is implemented via pseudo-differential architecture where the negative input (IN−) is held stable while the positive input (IN+) is sampled. The MAX1245BCPP achieves channel-to-channel crosstalk of −85dB and offset matching of ±0.2 LSB, making it suitable for precision differential sensing in noisy environments.

What serial interface protocols is the MAX1245BCPP compatible with?

The MAX1245BCPP supports SPI, QSPI, and MICROWIRE protocols natively via its 4-wire serial interface (CS, SCLK, DIN, DOUT), requiring no external level shifters or protocol translators. For SPI, CPOL = 0 and CPHA = 0 must be selected. Its SSTRB output also enables direct connection to TMS320-family DSPs for hardware-synchronized data capture - a capability not found in standard SPI peripherals. All timing parameters are validated per Maxim's datasheet for the MAX1245BCPP.