Analog Devices Inc. DC043A

Overview

DC043A from Linear Technology (now Analog Devices) is a micropower, 12-bit successive-approximation ADC in an 8-pin SOIC package. It features differential analog inputs, on-chip sample-and-hold, SPI/Microwire-compatible serial interface, 12.5 ksps sampling rate, and auto-shutdown to 1 nA typical supply current - enabling battery-operated remote sensor monitoring.

For engineers reviewing the DC043A datasheet, DC043A pinout, DC043A application, or DC043A equivalent, key selection criteria include its guaranteed ±3/4 LSB DNL, single-supply 4.5 V to 9 V operation, 60 µs conversion time, 250 µA typical active supply current, and compatibility with ratiometric transducer interfaces requiring high-impedance analog inputs.

Technical Context

The DC043A implements a switched-capacitor SAR architecture with integrated sample-and-hold and a synchronous 3-wire serial port (CS/CLK/DOUT). Its differential input stage supports floating common-mode voltages up to VCC, enabling direct connection to bridge sensors without level-shifting.

Conversion is initiated by a falling CS edge; data is output MSB-first on DOUT synchronized to CLK falling edges. The device automatically powers down between conversions when CS is high, reducing supply current to 1 nA - critical for energy-constrained IoT endpoints.

Key Specifications

Pinout & Package

DC043A is housed in an 8-lead plastic SOIC (S8) package with standard JEDEC outline and 1.27 mm pitch. Thermal resistance θJA = 130°C/W (C-grade) or 175°C/W (I-grade).

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS7822U and MAX11131ASA+, DC043A uniquely combines 12-bit accuracy, 12.5 ksps throughput, 4.5–9 V operation, and true nanoamp shutdown - making it optimal for long-life, wide-supply industrial sensor nodes where precision and energy efficiency are co-prioritized.

Availability

DC043A is available at Aetrix Electronics and suitable for battery-operated systems, remote data acquisition, and isolated data acquisition requiring stable component supply and long-term obsolescence support.

Supply support for DC043A 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

Analog Devices (formerly Linear Technology) is a global leader in high-performance analog, mixed-signal, and RF ICs, serving precision instrumentation, industrial automation, and aerospace markets.

The DC043A belongs to Linear's legacy micropower ADC family designed specifically for energy-constrained sensing applications - emphasizing ultra-low standby current, ratiometric flexibility, and robust serial interfacing in harsh environments.

FAQ

What is the maximum clock frequency supported by DC043A?

The DC043A supports a maximum clock frequency of 200 kHz when operating from a 5 V supply. At higher supply voltages (up to 9 V), the maximum clock frequency increases slightly - reaching ~290 kHz at 9 V - as confirmed in the Typical Performance Characteristics curve "Maximum Clock Frequency vs Supply Voltage". Exceeding these limits may cause conversion errors due to insufficient internal settling time.

Does DC043A require an external reference voltage?

No, DC043A does not require an external reference voltage. It supports ratiometric operation by accepting VCC as the reference input on Pin 1 (VREF), enabling direct connection to resistive sensors powered from the same rail. An external reference can be used for improved absolute accuracy, but the device functions fully with VREF tied to VCC within 4.5 V to 5.55 V range.

Can DC043A interface directly with a 3.3 V microcontroller?

Yes, DC043A can interface with a 3.3 V microcontroller, but level-shifting is required on the DOUT line when VCC > 3.3 V. Since DC043A's DOUT swings from 0 V to VCC, a resistor divider or dedicated level translator must be used to prevent overvoltage damage to the MCU input. CS and CLK inputs are TTL-compatible and accept 3.3 V logic levels safely across the full 4.5–9 V VCC range.

What is the analog input impedance of DC043A?

The DC043A analog input impedance is >5 MΩ for on-channel inputs and >50 kΩ for off-channel inputs, as specified in the "Analog Input Leakage Current" parameter (±1 µA max). This high impedance enables direct connection to high-output-impedance sensors like thermistors and RTDs without loading error - provided source resistance remains below 1 kΩ for <0.1 LSB error per the "Sample and Hold Acquisition Time vs Source Resistance" plot.

How does DC043A achieve 1 nA shutdown current?

DC043A achieves 1 nA shutdown current by internally disabling all bias circuits, comparator, and reference buffer when CS is driven high to VCC. This deep shutdown state is independent of CLK activity - the device draws only leakage current regardless of clock frequency or state. To maintain this spec, CS must be driven rail-to-rail (0 V low, VCC high); partial swings increase input buffer current and degrade shutdown performance.