AD678AJ - 12-Bit 200 kSPS Flash ADC | Analog Devices
MPN: AD678AJ ✗ End of Life| Qty | Unit Price | Extended |
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| 1 | $0 | $0.00 |
| 10 | $0 | $0.00 |
| 100 | $0 | $0.00 |
| 500 | $0 | $0.00 |
| 1,000 | $0 | $0.00 |
AD678AJ Overview
An ADC converts an analog voltage into a numerical digital value. This flash ADC belongs to the data-converter hierarchy and uses parallel output data, making it suitable for systems where a controller, microprocessor, or programmable logic device reads each conversion through dedicated data lines. Its integrated sample-and-hold amplifier supports sampled acquisition, while the internal voltage reference and clock-generation circuitry reduce the external support components required by a complete measurement channel.
The AD678AJ is specified for dynamic signal-processing performance, including signal-to-noise-plus-distortion ratio, total harmonic distortion, and intermodulation distortion. According to the Analog Devices product page, the AD678 shares its pinout with the 14-bit, 128 kSPS AD679, providing a documented upgrade path when a different resolution and conversion rate are acceptable. The same page also notes that MIL-STD-883-compliant versions are available, although the verified data does not establish that qualification for AD678AJ itself.
Typical uses include industrial data acquisition, process-control instrumentation, waveform sampling, communications receivers, and embedded measurement systems. Designers should use the manufacturer datasheet for the complete electrical limits, acquisition timing, reference behavior, interface logic, pin names, and recommended operating conditions. The 44-pin JLCC package is not one of the canonical package-diagram keys used by this output library, so its exact pinout and package drawing must be checked directly against the AD678 datasheet.
For replacement work, package and pinout compatibility must be established independently from functional similarity. AD678AJ is a through-hole 44-JLCC device; the verified cross-reference results do not identify a manufacturer-confirmed, same-package, pin-to-pin substitute. Distributor availability, pricing, and lifecycle status also require current quotation or inventory confirmation.
This page combines the verified AD678 manufacturer information, distributor specifications, package details, upgrade-path information, and sourcing links. It is intended to support engineers evaluating the AD678AJ for precision sampling systems while clearly separating verified data from information that must be confirmed from the datasheet or an authorized distributor.
Drop-in alternatives for AD678AJ — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
AD679
✅ Drop-In📋 Reference alternative (not in catalog)
AD678AJ Maximum Ratings & Electrical Characteristics
| ADC Type | Flash analog-to-digital converter |
| Resolution | 12 bit |
| Sampling Rate | 200 kSPS |
| Input Channels | 1 channel |
| Conversion Architecture | Flash |
| Output Interface | Parallel microprocessor-compatible bus |
| Sample-and-Hold Amplifier | Integrated |
| Voltage Reference | Integrated |
| Clock Generation Circuitry | Integrated |
| Signal Processing Metrics | S/N+D, THD, and IMD specified |
| Package | 44-pin JLCC ceramic package, 16.39 x 16.39 mm |
| Mounting Type | Through-hole |
| AD679 Pin Compatibility | Same pinout as the AD679 |
| AD679 Resolution | 14 bit |
| AD679 Sampling Rate | 128 kSPS |
| Military Availability | MIL-STD-883-compliant versions are stated as available; AD678AJ qualification requires verification |
| RoHS Status | unknown |
AD678AJ 44-pin jlcc ceramic package, 16.39 x 16.39 mm Pin Configuration Guide
Pin configuration for AD678AJ (44-pin jlcc ceramic package, 16.39 x 16.39 mm package). This analog component features input, output, and power supply pins. Refer to the manufacturer datasheet for offset null, compensation, and enable pin configurations. Ideal for signal conditioning and amplifier circuits.
No detailed pinout data available for AD678AJ.
Refer to the datasheet for full pin configuration.
Typical Applications
AD678AJ is suitable for 7 applications: Industrial Data Acquisition, Waveform Sampling, Communications Receiver, Process-Control Instrumentation, Audio and Dynamic Signal Measurement, Embedded Measurement Controller, Test and Measurement Equipment.
Industrial Data Acquisition
AD678AJ fits a sampled industrial measurement channel where a 12-bit result and 200 kSPS conversion throughput are useful for process variables, waveforms, and supervisory control. Its integrated sample-and-hold amplifier, reference, clock-generation circuitry, and microprocessor-compatible bus help reduce the number of separate analog-support blocks. The 44-JLCC through-hole package is useful for rugged or serviceable equipment, but the board must follow the verified 16.39 x 16.39 mm package dimensions. Designers should verify supply voltage, input range, acquisition timing, and logic levels from the manufacturer datasheet before finalizing the front end.
Recommended
Waveform Sampling
The AD678AJ's 200 kSPS sampling capability makes it a candidate for waveform acquisition in instrumentation and embedded test equipment. Its 12-bit quantization provides a higher resolution than an 8-bit sampler, while the flash architecture is intended for high-rate conversion. A practical design must account for analog bandwidth, anti-alias filtering, acquisition time, input drive, and digital data capture. The AD679 is not a drop-in performance substitute because it provides 14-bit resolution at 128 kSPS, so system timing must be selected for the intended sampling bandwidth.
Recommended
Communications Receiver
AD678AJ can be evaluated for communications receiver and IF-monitoring systems requiring 12-bit sampled data at up to 200 kSPS. The parallel interface provides direct connection to digital logic or a processor when the system is designed around the ADC's timing and output coding. Signal-chain performance depends on the RF or IF front end, filtering, reference stability, and gain distribution; the ADC does not eliminate those requirements. Use the datasheet's dynamic specifications, including S/N+D, THD, and IMD, to select gain and ensure that converter performance is not the limiting noise or distortion source.
Recommended
Process-Control Instrumentation
AD678AJ is appropriate for process-control measurements when 12-bit data is sufficient for the control loop and a moderate sampling rate meets the response requirement. The integrated reference and sample-and-hold amplifier simplify the analog front-end organization, while the microprocessor-compatible bus can feed a controller or digital signal processor. For reliable process measurements, the engineer must define input range, sensor excitation, grounding, shielding, calibration, and isolation requirements. The 44-JLCC package supports through-hole assembly, but vibration, thermal cycling, and connector stress should be evaluated at the system level.
Recommended
Audio and Dynamic Signal Measurement
AD678AJ may be considered for audio-band or dynamic signal measurement designs that need 12-bit conversion and dynamic characterization rather than only static DC accuracy. The manufacturer's documentation identifies S/N+D, THD, and IMD as important specifications for signal processing, allowing the system designer to compare distortion and noise requirements directly. The ADC should be paired with suitable input scaling, anti-alias filtering, and a low-noise reference path. Its 200 kSPS rate is higher than the AD679's 128 kSPS, but the two parts should not be treated as identical replacements because their resolution and timing differ.
Recommended
Embedded Measurement Controller
AD678AJ can serve as the conversion element in an embedded measurement controller when a parallel bus is preferable to a serial interface. Its one-channel structure and integrated clock, reference, and sample-and-hold functions make it straightforward to partition the design into analog conditioning, ADC conversion, digital acquisition, and control. The controller must still define data-bus timing, chip-select behavior, conversion-status handling, and error margins around the manufacturer's operating limits. Because the verified information does not include complete timing values or logic levels, those details must be taken directly from the AD678 datasheet before firmware and PCB signoff.
Recommended
Test and Measurement Equipment
AD678AJ is a candidate for laboratory and field test systems that need a reproducible 12-bit measurement channel at 200 kSPS. The parallel output can feed counters, FIFOs, or a processor, while the integrated reference and sample-and-hold stages help define a controlled acquisition front end. Calibration procedures should characterize offset, gain, reference drift, and distortion across the intended input bandwidth. Engineers should not assume that resolution alone determines accuracy: connector layout, grounding, shielding, clock jitter, power-supply noise, and thermal stability can dominate the final result.
Recommended
Recommended Products Summary
Engineering reference data for AD678AJ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AD679 |
|---|---|---|
| Brand | Analog Devices | Analog Devices |
| Package | 44-pin JLCC ceramic package, 16.39 x 16.39 mm | Same pinout as AD678; exact package drawing requires verification |
| ADC Resolution | 12 bit | 14 bit |
| Sampling Rate | 200 kSPS | 128 kSPS |
| Input Channels | 1 channel | 1 channel; exact specification requires datasheet verification |
| Architecture | Flash ADC | ADC; detailed architecture requires datasheet verification |
| Output Interface | Parallel microprocessor-compatible bus | Same pinout; exact interface details require datasheet verification |
| Integrated Functions | Sample-and-hold amplifier, voltage reference, clock generation | Refer to the current AD679 datasheet |
| Upgrade Path | AD678 shares the pinout of AD679 | Pin-compatible relationship stated by Analog Devices |
| Dynamic Performance | S/N+D, THD, and IMD specified | Exact values not provided in verified data |
| Military Note | MIL-STD-883-compliant versions are stated as available; AD678AJ qualification not verified | Exact qualification status not provided in verified data |
Key Differentiators
- Higher sampling throughput than the documented AD679 comparison part (vs AD679)
- Documented relationship to the AD679 pinout (vs AD679)
- Integrated acquisition support (vs AD679)
- Verified ceramic through-hole package construction (vs AD678BD)
Design Notes
AD678AJ is a through-hole 44-pin JLCC device, so PCB layout should reserve the verified 16.39 x 16.39 mm ceramic package footprint, adequate lead-clearance space, and a mechanical keepout around the body. Confirm pin numbering against the official package drawing before routing. Keep analog input traces away from digital data and clock lines, and provide a low-impedance ground return for the reference and supply connections.
The AD678AJ combines a sample-and-hold amplifier with a parallel digital bus, so timing margin and return paths are important. Route clock, control, and output signals with continuous ground references, terminate or buffer them according to the connected logic, and avoid long unprotected parallel-bus traces. Verify acquisition timing and output settling against the manufacturer datasheet; the supplied data does not provide complete timing limits.
Decouple the analog and digital supplies at the device pins using the capacitance and placement recommendations in the AD678 datasheet. Keep the reference and analog return current physically close to their corresponding signal paths, and isolate switching converters and high-current digital returns. Because the verified data does not state supply voltage or current limits, do not select capacitors or regulators by estimate; verify those values first.
Do not treat the AD679 as a drop-in electrical equivalent simply because Analog Devices states that the AD678 and AD679 share a pinout. AD678AJ is 12-bit at 200 kSPS, whereas AD679 is 14-bit at 128 kSPS. Also, the 44-JLCC package must not be confused with CDIP-28 variants appearing in comparison listings. Validate package, timing, logic, supply, and performance before any replacement.
Compliance Information
The verified manufacturer page states that versions compliant with MIL-STD-883 are available, but the supplied data does not establish the qualification status of AD678AJ. RoHS, REACH, lead-free, halogen-free, and conflict-minerals information are not verified for this exact MPN.
