AD574AJDZ - 12-Bit SAR ADC, 28-CDIP | Analog Devices
MPN: AD574AJDZ ✓ Hoạt độngAD574AJDZ Tóm tắt
An SAR analog-to-digital converter is a type of data converter that performs a binary search across an internal capacitive DAC to digitize an analog input in N clock cycles, where N equals the converter resolution. Compared with flash, sigma-delta, and dual-slope architectures, the SAR topology combines high throughput (tens to hundreds of ksps), low latency, no pipeline delay, and excellent DC linearity - making it the dominant architecture for 12-16 bit precision measurement, industrial data acquisition, and instrumentation applications. The AD574A family is widely regarded as the industry-standard 12-bit ADC and has been in continuous production since the early 1980s.
Key features of the AD574AJDZ include 12-bit resolution with 35 us maximum conversion time, factory-calibrated linearity (no missing codes), four software-configurable input ranges (0 to +10 V, 0 to +20 V, -5 to +5 V, -10 to +10 V), and 8/16-bit microprocessor bus compatibility with standard read/write control logic. The on-chip reference and clock eliminate two of the largest external component costs typical of older 12-bit ADC designs.
Architecturally, the AD574A combines a precision laser-trimmed thin-film DAC, a high-speed comparator, a successive-approximation register, and a 10 V buried Zener reference - all on a single bipolar/CMOS die. This integration produces full-rated performance without user calibration, a major advantage over the modular ADC boards of the era. The hermetic 28-CDIP package supports the J-grade (-55C to +125C) temperature range required for military and aerospace programs.
Typical applications include precision industrial data acquisition systems, military/aerospace avionics signal conditioning, automated test equipment (ATE), process-control front ends, and high-reliability instrumentation requiring the extended-temperature ceramic package. The wide input range and 12-bit linearity suit multi-channel multiplexed front ends with PGA conditioning.
When designing with the AD574AJDZ, allocate 200 ns bus-access timing margins and place a 100 nF bypass capacitor within 5 mm of each supply pin to suppress the high-current switching transients inherent to the SAR architecture. The ceramic DIP is intended for through-hole sockets on MIL-STD-810 and MIL-PRF-38534 compliant boards; for surface-mount designs, the AD574AUD (28-SOIC) is a recommended drop-in electrical equivalent.
Bộ thay thế dễ dàng lắp đặt cho AD574AJDZ — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với AD574AJDZ (cùng hình factor và footprint) — khác nhau ở Architecture, Conversion Time, Internal Clock, Mounting Type, Operating Temperature.
AD574AKDZ
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD574ATDZ
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD574AUD
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ADC574ASH
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD1674AJDZ
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD674BJDZ
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD574AJDZ Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 12 bit |
| Architecture | SAR (Successive Approximation) |
| Number of Channels | 1 |
| Conversion Time | 35 us max |
| Input Range | 0 to +10 V / 0 to +20 V / -5 to +5 V / -10 to +10 V (software configurable) |
| Input Type | Single-ended |
| Data Interface | Parallel (8/16-bit microprocessor bus) |
| Reference Type | Internal 10 V buried Zener |
| Internal Clock | Yes |
| Supply Voltage VCC | +12 V to +15 V nominal |
| Supply Voltage VLOGIC | +5 V |
| Supply Voltage VEE | -12 V to -15 V nominal |
| Nhiệt độ hoạt động | -55C to +125C (J grade) |
| Hộp | 28-CDIP (Side Brazed Ceramic DIP) |
| Kiểu lắp đặt | Through-Hole |
Cấu hình chân AD574AJDZ
| Chân 1 | VCC — +12 V or +15 V analog supply |
| Chân 2 | 12/8 — Bus width select (12 or 8 bit output) |
| Chân 3 | CS — Chip Select (active low) |
| Chân 4 | A0 |
| Chân 5 | R/C — Read/Convert control |
| Chân 6 | CE — Chip Enable (active high) |
| Chân 7 | VEE — -12 V or -15 V analog supply |
| Chân 8 | BIP OFF — Bipolar offset adjustment |
| Chân 9 | AIN (10V) — Analog input, 0-10 V range |
| Chân 10 | AIN (20V) — Analog input, 0-20 V range |
| Chân 11 | REF OUT — Internal 10 V reference output |
| Chân 12 | REF IN — Reference input (internal/external select) |
| Chân 13 | AGND — Analog ground |
| Chân 14 | DB11 (MSB) — Data bit 11 (MSB) |
| Chân 15 | DB10 — Data bit 10 |
| Chân 16 | DB9 — Data bit 9 |
| Chân 17 | DB8 — Data bit 8 |
| Chân 18 | STS — Status output (active high during conversion) |
| Chân 19 | DB7 — Data bit 7 |
| Chân 20 | DB6 — Data bit 6 |
| Chân 21 | DB5 — Data bit 5 |
| Chân 22 | DB4 — Data bit 4 |
| Chân 23 | DB3 — Data bit 3 |
| Chân 24 | DB2 — Data bit 2 |
| Chân 25 | DB1 — Data bit 1 |
| Chân 26 | DB0 (LSB) — Data bit 0 (LSB) |
| Chân 27 | DGND — Digital ground |
| Chân 28 | VLOGIC — +5 V logic supply |
Ứng dụng tiêu biểu
AD574AJDZ phù hợp cho 6 Áp dụngs: Precision Industrial Data Acquisition Systems, Military and Aerospace Avionics, Automated Test Equipment (ATE), Process Control and Industrial Sensors, High-Reliability Medical Instrumentation, Legacy Microprocessor-Based Measurement Boards.
Precision Industrial Data Acquisition Systems
The AD574AJDZ is well suited as the front-end ADC in multi-channel industrial data acquisition systems where -55C to +125C operation, 12-bit linearity, and four software-selectable input ranges are required. Its 35 us conversion time allows channel rates above 25 ksps when multiplexed, and the internal 10 V Zener reference eliminates a major external component cost. Pairing the part with an instrumentation amplifier such as the AD620 and an analog multiplexer such as the ADG506A yields a 16-channel precision DAS that meets MIL-STD-810 environmental specs. The 28-CDIP footprint is directly compatible with MIL-PRF-38534 qualified PCB layouts.
Được đề xuất
Military and Aerospace Avionics
The AD574AJDZ J-grade temperature range (-55C to +125C) and hermetic 28-CDIP ceramic package qualify the part for military avionics, missile telemetry, and aerospace signal-conditioning designs. The 12-bit SAR architecture provides deterministic conversion latency - critical for synchronous sampled-data control loops where pipeline or delta-sigma delays are unacceptable. The integrated reference and bus interface simplify the BOM for flight-qualified boards subject to MIL-PRF-38534 Class H or K screening. Designers commonly pair the part with radiation-hardened processors in redundant flight-control channels.
Được đề xuất
Automated Test Equipment (ATE)
In bench-top and rack-mounted automated test equipment, the AD574AJDZ provides a well-characterized 12-bit measurement channel with 35 us conversion time and direct 8/16-bit microprocessor bus interface. The four configurable input ranges cover the typical +/-10 V bench DMM envelope, allowing a single ADC design to digitize voltage, current (via shunt), and transducer outputs. The hermetic CDIP package supports long-lifecycle ATE platforms where the same hardware must remain in production for 15-20 years and field replacement parts must match exactly. Pairing the ADC with a precision front-end multiplexer and instrumentation amp produces a calibrated analog measurement subsystem.
Được đề xuất
Process Control and Industrial Sensors
Process-control front ends digitize 4-20 mA current loops, RTD, and thermocouple signals through scaling amplifiers and then into the AD574AJDZ ADC. The -55C to +125C J-grade operating range supports outdoor, sub-station, and refinery instrumentation enclosures where ambient temperatures can swing dramatically. The ADC's +/-10 V bipolar input range simplifies signal-conditioning scaling for thermocouple-mV inputs and current-loop-derived 1-5 V signals. The 3-state parallel output buffer allows direct connection to legacy 8-bit microcontrollers (8051, 68HC11) still common in long-lifecycle process controllers.
Được đề xuất
High-Reliability Medical Instrumentation
The AD574AJDZ is widely used in medical instrumentation designs that require high-reliability, hermetic packaging, and long-term component traceability. The 12-bit SAR conversion provides deterministic sampling for patient-monitoring waveforms (ECG, SpO2, blood pressure) where pipeline delay cannot be tolerated. The four input ranges accommodate the +/-5 mV to +/-10 V signal envelope of biopotential and pressure transducers after front-end gain. The 28-CDIP package is preferred for medical devices designed for MIL-STD-810-style environmental qualification, including portable defibrillators and infusion pumps.
Được đề xuất
Legacy Microprocessor-Based Measurement Boards
The AD574AJDZ was designed specifically for direct connection to 8-bit microprocessors (8085, Z80, 68HC11) and 16-bit microprocessors (8086, 68000) of the 1980s-1990s, and it remains the ADC of choice for maintaining, repairing, or designing new boards around these legacy controllers. The 3-state parallel bus, status-flag handshake, and standard read/write control logic map directly to memory-mapped I/O address spaces. Modernized variants of these legacy designs - particularly in industrial controllers, programmable logic controllers (PLCs), and CNC machines - continue to specify the AD574A family for backward compatibility and second-source stability.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho AD574AJDZ — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | AD574AKDZ | AD574ATDZ | AD574AUD | ADC574ASH | AD1674AJDZ | AD674BJDZ |
|---|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 28-CDIP (side-brazed ceramic DIP) | 28-CDIP (side-brazed ceramic DIP) - same | 28-CDIP (side-brazed ceramic DIP) - same | 28-SOIC - surface mount equivalent | 28-CDIP - same | 28-CDIP - same | 28-CDIP - same |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit |
| Conversion Time | 35 us max | 35 us max | 35 us max | 35 us max | 35 us max | 10 us max (faster) | 15 us max |
| Operating Temperature | -55C to +125C (J grade) | -55C to +125C (K grade) | -40C to +85C (T grade) | -55C to +125C (U grade SOIC) | -55C to +125C | -55C to +125C | -55C to +125C |
| Internal Reference | 10 V buried Zener | 10 V buried Zener | 10 V buried Zener | 10 V buried Zener | 10 V buried Zener | 10 V buried Zener | 10 V buried Zener |
| Input Ranges | 0-10V / 0-20V / +/-5V / +/-10V | 0-10V / 0-20V / +/-5V / +/-10V | 0-10V / 0-20V / +/-5V / +/-10V | 0-10V / 0-20V / +/-5V / +/-10V | 0-10V / 0-20V / +/-5V / +/-10V | 0-10V / 0-20V / +/-5V / +/-10V | 0-10V / 0-20V / +/-5V / +/-10V |
| Data Interface | Parallel 8/16-bit | Parallel 8/16-bit | Parallel 8/16-bit | Parallel 8/16-bit | Parallel 8/16-bit | Parallel 8/16-bit | Parallel 8/16-bit |
Bảo phân biệt quan trọng
- J-grade -55C to +125C MIL temperature range with hermetic 28-CDIP ceramic package (vsAD574ATDZ)
- Through-hole 28-CDIP for MIL-PRF-38534 compliant boards (vsAD574AUD)
- 35 us conversion time with full 12-bit no-missing-codes linearity (vsAD1674AJDZ)
Ghi chú thiết kế
The AD574AJDZ requires three separate supplies: +12 V or +15 V (VCC), +5 V (VLOGIC), and -12 V or -15 V (VEE). Place a 100 nF ceramic bypass capacitor within 5 mm of each supply pin (pins 1, 7, 28) and a 10 uF tantalum bulk capacitor on each rail. The negative supply is critical - inadequate VEE bypassing causes linearity degradation and increased conversion noise. Per the Analog Devices datasheet, power-up sequencing is not strictly required but VLOGIC should be present within 100 ms of VCC to avoid latch-up.
Use a split analog/digital ground plane with a single tie-point near the AD574AJDZ AGND pin (pin 13). Route all analog inputs and the reference decoupling on the analog plane, and all digital bus lines (DB0-DB11, CS, CE, R/C, STS) on the digital plane. Keep the analog input traces short and guarded with ground traces to minimize pickup of digital switching noise - a major source of ADC linearity degradation in SAR designs.
The 12/8 pin (pin 2) must be hard-wired to VLOGIC for 12-bit parallel output or to DGND for two-byte 8-bit output - this pin is not TTL-compatible and floating it causes intermittent bus-read errors. The bipolar offset trim (pin 8) must be left floating for unipolar operation; for bipolar ranges, attach a 10 kohm potentiometer to AGND to null the offset. The reference input pin (pin 12) must be connected to REF OUT (pin 11) for internal reference operation - omitting this connection causes the ADC to produce out-of-range codes.
Thông tin tuân thủ
AD574AJDZ is a MIL-temperature grade part in ceramic DIP packaging; full RoHS/REACH/lead-free status should be confirmed on the Analog Devices product page or by requesting a compliance certificate. AEC-Q100 is not applicable for this through-hole industrial/aerospace part.
