Analog Devices Inc. HAS-1204SM

Overview

HAS-1204SM from Analog Devices is a hermetically sealed, 12-bit successive-approximation analog-to-digital converter (ADC) with integrated track-and-hold amplifier, encoder, and timing circuits in a 40-pin metal DIP package. It delivers 500 kHz word rate, 2.0 µs max conversion time, 7 MHz small-signal T/H bandwidth, and operates across –55°C to +100°C for rugged instrumentation applications.

For engineers reviewing the HAS-1204SM datasheet, HAS-1204SM pinout, HAS-1204SM application, or HAS-1204SM equivalent, key selection considerations include its self-contained architecture, TTL-compatible encode command interface, parallel/serial digital outputs, unipolar/bipolar input range support, and thermal performance validated over extended military-grade temperature range.

Technical Context

The HAS-1204SM implements a successive-approximation register (SAR) architecture with an internal high-speed D/A converter and comparator. Its monolithic hybrid construction integrates the track-and-hold amplifier, encoder logic, and timing generation - eliminating external clocking or control circuitry.

It supports dual analog input ranges (0 to –5 V / 0 to –10 V unipolar; ±2.5 V / ±5 V bipolar), uses TTL-compatible encode command triggering, and provides both parallel NRZ (12-bit) and serial RZ digital outputs synchronized to an internal clock derived from the encode pulse.

Key Specifications

Pinout & Package

Package: 40-pin hermetically sealed metal DIP (dual in-line package), dimensions 1.900" × 0.750" × 0.250" (48.26 mm × 19.05 mm × 6.35 mm), with bottom-view pin numbering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7892BRZ and MAX195BCPP, the HAS-1204SM uniquely combines military-temperature operation, integrated T/H, parallel+serial outputs, and complete timing autonomy - making it irreplaceable in legacy or ruggedized systems where minimal external components and guaranteed long-term availability are mandatory.

Availability

HAS-1204SM is available at Aetrix Electronics and suitable for medical instrumentation, radar systems, and test equipment requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for HAS-1204SM 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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, headquartered in Wilmington, MA.

The HAS-1204SM belongs to Analog Devices' legacy high-speed hybrid ADC family, designed specifically for demanding instrumentation and defense applications where integration, reliability, and extended environmental operation outweigh cost or miniaturization goals.

FAQ

What is the operating temperature range specified for the HAS-1204SM?

The HAS-1204SM is rated for continuous operation from –55°C to +100°C. This extended range is explicitly defined in the ordering information and distinguishes it from the HAS-1204BM (–25°C to +85°C). Thermal resistance values (θ_JA = 25°C/W, θ_JC = 16°C/W) and mandatory 500 CFM airflow requirement are provided to ensure junction temperature remains below 150°C under full-load conditions. The HAS-1204SM must be mounted with appropriate heatsinking and forced-air cooling in high-temperature environments.

Does the HAS-1204SM require external clock circuitry to operate?

No, the HAS-1204SM does not require an external clock. Its encode command input (Pin 1) is a TTL-compatible signal whose rising edge initiates the entire conversion sequence - including internal clock generation, track-to-hold transition, and successive approximation. All timing signals (including the 12-clock pulse train on Pin 22 and Data Ready on Pin 2) are derived internally. This self-timed architecture eliminates clock distribution skew and external oscillator dependencies, simplifying system design.

How is bipolar versus unipolar mode configured on the HAS-1204SM?

Bipolar mode on the HAS-1204SM is enabled by installing a short jumper between Pins 28 (D/A Output) and 29 (Bipolar Offset); unipolar mode requires connecting Pin 29 to ground. This hardware-selectable configuration determines whether the analog input range interprets signals as 0 to –5 V (unipolar) or ±2.5 V (bipolar). The offset and gain adjustments described in Figures 3 and 4 must be performed in the selected mode, using the corresponding voltage references and dither targets shown in the datasheet.

What digital output formats does the HAS-1204SM support?

The HAS-1204SM provides both parallel and serial digital outputs simultaneously. Parallel output appears on Pins 7–20 as 12-bit NRZ TTL-level data (BIT1 MSB to BIT12 LSB). Serial output is available on Pin 21 in RZ format, synchronized to the internal clock pulses on Pin 22. The Data Ready signal (Pin 2) is an RZ strobe whose falling edge is recommended for latching parallel data; serial data validity aligns with the trailing edge of each clock pulse.

Is the HAS-1204SM still in active production or considered obsolete?

The HAS-1204SM is marked "OBSOLETE" in the provided documentation, consistent with Analog Devices' discontinuation of this hybrid ADC family. However, Aetrix Electronics maintains verified legacy inventory with full traceability and extended lifecycle support. Units are screened, tested, and supplied with original manufacturer markings and packaging. For new designs, engineering consultation is recommended - but for repair, sustainment, or legacy system refresh, the HAS-1204SM remains fully supported with documented specifications and application guidance.