MAX174BCPI - 12-Bit 8µs SAR ADC with Reference | Maxim Integrated | PDIP-28
MPN: MAX174BCPI ✗ Cuối đờiMAX174BCPI Tóm tắt
A SAR ADC is a successive-approximation-register analog-to-digital converter, which is a subtype of ADC that uses a binary-search algorithm against an internal DAC to digitize an analog input in N clock cycles for N bits of resolution. SAR ADCs occupy the middle ground in the ADC taxonomy: they offer higher speed than integrating or delta-sigma converters but lower speed than flash ADCs, while delivering excellent DC accuracy, low latency, and low power consumption without the switching noise inherent to delta-sigma architectures. The MAX174 belongs to the broader category of data-acquisition ICs, which sit within signal-chain components and ultimately within the power-management-and-analog IC family of semiconductors.
Key features include 12-bit resolution with no missing codes, ±0.5 LSB maximum integral nonlinearity (INL), and a track/hold amplifier capable of digitizing signals up to its Nyquist bandwidth. The device operates from ±12V or ±15V supplies, drawing typically 80 mW, with a power-down mode that reduces consumption to under 5 mW between conversions. The 8µs conversion time translates to a 125 kHz throughput, suitable for high-speed industrial control loops and multi-channel multiplexing systems.
The internal architecture uses a capacitive-charge-redistribution DAC for the SAR loop, a precision buried-zener reference laser-trimmed for low drift, and a self-biasing bipolar front end that accepts true bipolar input signals without external signal conditioning. The device includes control logic that allows direct connection to microprocessors via the 12-bit parallel bus, with standard CS, RD, and BUSY handshake signals compatible with 8080-family processor interfaces.
Typical applications include industrial process-control data acquisition, digital panel meters, instrumentation amplifiers digitizing strain-gauge signals, multi-channel data-logging multiplexed systems, and benchtop test-and-measurement equipment. The wide bipolar input range makes it particularly attractive in legacy 12-bit data-acquisition boards where direct connection to ±10V transducer outputs is required without external resistor attenuators or level-shift circuits.
When designing with this device, ensure the power-supply bypass network uses 10 µF tantalum in parallel with 0.1 µF ceramic at each supply pin; failure to provide adequate decoupling degrades the reference noise and INL. The analog input must be protected with an external op-amp buffer or low-impedance driving source to avoid kick-back from the internal capacitive DAC, which would otherwise introduce settling errors at the rated 8 µs conversion speed.
This page synthesizes distributor pricing, drop-in alternatives, application guidance, and design notes not aggregated on the manufacturer datasheet, providing an engineer-ready summary for sourcing and design-in decisions.
Bộ thay thế dễ dàng lắp đặt cho MAX174BCPI — 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 MAX174BCPI (cùng hình factor và footprint) — khác nhau ở RoHS Status, Mounting Type, Architecture, Data Interface, Operating Temperature Range.
MAX174BEPI+
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX174BCPI+
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX174AEPI
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MAX674ACPI
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
AD574AJNZ
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX174BCPI Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 12 bits |
| Architecture | SAR (Successive Approximation Register) |
| Number of Input Channels | 1 |
| Maximum Conversion Time | 8 µs |
| Integral Non-Linearity (INL) | ±0.5 LSB (max) |
| Analog Input Range | ±5V, ±10V, 0-10V, 0-15V (unipolar or bipolar, jumper-selectable) |
| Điện áp cung cấp | ±12V or ±15V dual supply |
| Power Consumption (active) | 80 mW (typical) |
| Internal Reference | 10V buried-zener, laser-trimmed |
| Internal Clock | Yes |
| Digital Interface | 12-bit parallel, microprocessor-compatible |
| Hộp | 28-pin PDIP (N-28) |
| Khoảng nhiệt độ hoạt động | 0°C to +70°C (commercial grade, 'C' suffix) |
| Kiểu lắp đặt | Through-Hole (PDIP) |
| Trạng thái RoHS | Non-Compliant (PDIP with SnPb finish) |
Cấu hình chân MAX174BCPI
| Chân 1 | VSS (-15V) — Negative analog supply (-12V to -15V) |
| Chân 2 | VLOGIC (+5V) — Logic supply (+5V) for digital interface |
| Chân 3 | /CS — Chip select (active low) |
| Chân 4 | /RD — Read input (active low) |
| Chân 5 | /BUSY — Busy/status output (active low during conversion) |
| Chân 6 | 1.2V — Reference-decoupling node, bypass with 0.1µF capacitor |
| Chân 7 | GND — Analog ground |
| Chân 8 | REF OUT — +10V reference output (internal buried-zener) |
| Chân 9 | REF ADJ — Reference-trim input (use 100kΩ pot for fine trim) |
| Chân 10 | REF IN — Reference voltage input (normally tied to REF OUT) |
| Chân 11 | BIP OFF — Bipolar offset (jumper-selectable for ±10V, ±5V, 0-10V, 0-15V modes) |
| Chân 12 | 10VIN/AIN — Analog input (full-scale set by input-range jumper) |
| Chân 13 | AGND — Analog ground return for input signal |
| Chân 14 | SENSE — Analog-range-select jumper terminal |
| Chân 15 | DB11 (MSB) — Parallel data bit 11 (MSB) |
| Chân 16 | DB10 — Parallel data bit 10 |
| Chân 17 | DB9 — Parallel data bit 9 |
| Chân 18 | DB8 — Parallel data bit 8 |
| Chân 19 | DB7 — Parallel data bit 7 |
| Chân 20 | DB6 — Parallel data bit 6 |
| Chân 21 | DB5 — Parallel data bit 5 |
| Chân 22 | DB4 — Parallel data bit 4 |
| Chân 23 | DB3 — Parallel data bit 3 |
| Chân 24 | DB2 — Parallel data bit 2 |
| Chân 25 | DB1 — Parallel data bit 1 |
| Chân 26 | DB0 (LSB) — Parallel data bit 0 (LSB) |
| Chân 27 | DGND — Digital ground |
| Chân 28 | VDD (+15V) — Positive analog supply (+12V to +15V) |
Ứng dụng tiêu biểu
MAX174BCPI phù hợp cho 6 Áp dụngs: Industrial Process-Control Data Acquisition, Digital Panel Meters and Bench Instruments, Strain-Gauge and Bridge Sensor Digitization, Multiplexed Data-Logging Systems, Legacy Test and Measurement Equipment, Audio Signal Analysis and RF Power Metering.
Industrial Process-Control Data Acquisition
The MAX174BCPI suits 12-bit industrial data-acquisition boards because its bipolar ±10V and 0-15V input ranges directly accept the output of 4-20 mA current-loop receivers and strain-gauge bridges without external signal conditioning. Its integrated 10V buried-zener reference and 8µs conversion deliver a complete 125 kSPS SAR signal chain in one IC, reducing BOM cost versus multi-chip ADC designs. Operated on ±15V supplies, the device handles the ±10V common-mode range found in factory-floor analog I/O modules. The 28-pin PDIP form factor remains popular in legacy PLC analog input cards where through-hole replacement simplifies service and firmware qualification. A typical circuit uses an AD620 instrumentation amp upstream, the MAX174 on the ADC slot, and a 74HC573 latch for bus sharing with the host microcontroller.
Được đề xuất
Digital Panel Meters and Bench Instruments
The MAX174BCPI delivers the resolution, bipolar input range, and integrated reference required by 4½-digit digital panel meters (DPMs) and bench instruments. Its 12-bit resolution with no missing codes offers >99.97% theoretical DNL, which translates to stable readings without flicker at the lowest digit, and the on-chip 10V reference allows direct calibration against external standards. The 8µs conversion rate supports update rates above 10 Hz typical for DPM readouts, while the 12-bit parallel interface is easily read by 8051, PIC, and PIC32 microcontrollers. The ±15V supply connects directly to the analog front end of typical bench instruments, eliminating the boost-stage typically required for ±15V rail generation. The 28-pin PDIP is well-suited to mains-powered bench instruments that use through-hole components for serviceability.
Được đề xuất
Strain-Gauge and Bridge Sensor Digitization
Bridge-transducer signal chains digitize microvolt-level outputs from load cells, pressure sensors, and strain gauges, and the MAX174BCPI's 12-bit resolution with a bipolar ±10V input range accommodates ratiometric excitation at 10V and full-scale outputs of up to ±30 mV after INA128 amplification. The internal 10V reference can be re-routed to drive the bridge excitation, eliminating the need for an external ratiometric reference and saving roughly $1 in BOM cost. The 8µs conversion enables oversampling and averaging with simple first-order FIR filters without missing real-time events. The parallel digital interface supports direct connection to FPGAs implementing digital filters that further improve effective resolution. The standard 28-pin PDIP package simplifies hand prototyping of load-cell and pressure-sensor instrumentation for OEM test fixtures.
Được đề xuất
Multiplexed Data-Logging Systems
Multi-channel data-logging designs pair the MAX174BCPI with an 8 or 16-channel analog multiplexer (CD4051, ADG608) to scan thermocouples, RTDs, and process currents at aggregate throughputs above 100 kSPS. The MAX174's 8µs conversion time provides ample settling margin for 8-channel scanning at typical 100 Hz per channel update rates, and its 12-bit resolution with no missing codes avoids channel-to-channel noise-spike errors. The internal clock eliminates the need for an external timing source, simplifying the BOM, while the digital /CS /RD /BUSY handshake remains compatible with simple 8051 or PIC16F I/O bit-banging. The 28-pin PDIP through-hole package suits industrial data loggers using legacy through-hole manufacturing. Designers often use two MAX174BCPI chips in parallel on the same bus for higher channel count where budget constraints preclude more-expensive 16-bit SAR ADCs.
Được đề xuất
Legacy Test and Measurement Equipment
The MAX174BCPI remains a staple in legacy ATE and bench-test designs because its 12-bit resolution and 8µs conversion form the building block of many 1980s- and 1990s-era data-acquisition cards still in service today. The bipolar ±10V input accepts most transducer outputs and audio test points directly, and its 12-bit parallel interface is straightforward to integrate into legacy VMEbus, ISA-bus, and GPIB-instrument architectures. The integrated 10V reference supports the 5-10V signal ranges typical of legacy ATE, while the +5V logic interface ensures compatibility with bipolar logic families (74LS, 74HC) still common in test instrumentation. Service and repair of legacy equipment is supported by the through-hole PDIP package and the long-term availability of the MAX174 family on the distributor secondary market.
Được đề xuất
Audio Signal Analysis and RF Power Metering
Audio-frequency analyzer and RF-power-meter front ends require signal-to-noise ratios that the MAX174BCPI's 12-bit dynamic range and integrated low-noise reference easily meet. With a unipolar 0-10V input range, the MAX174 can digitize buffered microphone preamp outputs or RF-detector voltages directly, and its 8µs conversion rate captures audio-bandwidth signals up to its Nyquist frequency. The internal 10V reference sets the full-scale calibration point precisely, and the parallel interface integrates with audio DSPs and microcontroller-based metering displays. The MAX174BCPI is often paired with a log detector (AD8307) or RMS-to-DC converter (AD736) for RF-power meters, where the ADC's bipolar ±10V input handles the wide dynamic range of detector outputs. The 28-pin PDIP is well-suited to audio- and RF-analog front-end boards that prefer through-hole parts for serviceability.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MAX174BCPI — 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 | MAX174BEPI+ | MAX174BCPI+ | MAX174AEPI | MAX674ACPI | AD574AJNZ |
|---|---|---|---|---|---|---|
| Brand | Analog Devices (Maxim Integrated) | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | PDIP-28 | PDIP-28 (same) | PDIP-28 (same) | PDIP-28 (same) | PDIP-28 (same) | PDIP-28 (same) |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Conversion Time | 8 µs | 8 µs | 8 µs | 8 µs | 15 µs | 25 µs |
| Input Range | ±5/±10/0-10/0-15V bipolar | ±5/±10/0-10/0-15V | ±5/±10/0-10/0-15V | ±5/±10/0-10/0-15V | ±5/±10/0-10/0-15V | ±5/±10/0-10/0-15V |
| INL (max) | ±0.5 LSB | ±0.5 LSB (trim options) | ±0.5 LSB | ±0.5 LSB | ±0.5 LSB | ±1 LSB |
| Internal Reference | 10V buried-zener | 10V | 10V | 10V | 10V | 10V |
| Power Consumption | 80 mW (typical) | 80 mW | 80 mW | 80 mW | 115 mW | 120 mW |
| RoHS Compliance | Non-compliant (SnPb) | RoHS compliant | RoHS compliant | Non-compliant (SnPb) | Non-compliant (SnPb) | RoHS compliant |
| Lifecycle Status | Obsolete (no longer manufactured) | Limited / Last time buy | Obsolete | Limited | Obsolete | Active |
Bảo phân biệt quan trọng
- Faster 8µs conversion in the same PDIP-28 family (vsMAX674ACPI)
- Industrial ±15V bipolar operation in legacy through-hole form (vsMAX176ACPA+)
- Complete ADC with integrated 10V reference and clock (vsAD574AJNZ)
Ghi chú thiết kế
Estimated: at ±15V dual supplies the MAX174BCPI draws approximately 80 mW quiescent (3 mA from each rail), which means each ±15V pin requires a local 10 µF tantalum + 0.1 µF ceramic bypass network for clean reference voltage. Failure to provide adequate decoupling introduces 5-10 mV of reference noise that will visibly degrade INL. Designers should also decouple the +5V logic supply at pin 2 with a separate 0.1 µF ceramic capacitor to prevent digital switching noise from coupling into the analog reference. A common-mode choke between analog and digital supplies further reduces noise injection by 6-10 dB in industrial environments.
The MAX174BCPI's analog ground (pin 7, 13) and digital ground (pin 27) MUST join at a single star-point ground located directly under the IC, with the analog ground return path undisturbed by digital return currents. This single-point grounding scheme is the manufacturer's recommended pattern; splitting grounds elsewhere causes ground-loop errors of 1-3 LSB and produces 'noisy bottom bits' visible in the parallel data output. The analog input pin (pin 12) should be guarded on both sides of the PCB with low-impedance ground traces to minimize leakage and capacitive pickup of nearby digital signals.
The MAX174BCPI's input sample-and-hold has a 50-100 pF equivalent input capacitance at the start of each conversion, causing 'kick-back' current transients to the driving op-amp. Source impedance above 1 kΩ requires a wideband op-amp buffer (such as the AD845) with adequate slew rate (40 V/µs+) to settle within 1 µs after sampling. Lower-speed op-amps (e.g., OP07) introduce 2-3 LSB settling errors at the rated 8 µs conversion time. For applications sampling dynamic signals, place a 1 nF NP0 capacitor close to pin 12 to provide instantaneous charge for the sample-and-hold and reduce kick-back by 50%.
Do not exceed the supply sequence: apply analog supplies (±15V) BEFORE the +5V logic supply. Reversing this sequence can latch the device into a state where the parallel outputs drive the bus, potentially damaging host microcontroller I/O pins. When entering power-down (CS high, RD high), allow at least 5 µs for full output high-impedance release before driving the bus from another source. Finally, the /BUSY signal is open-collector in some revisions and push-pull in others; consult your specific datasheet revision before sizing the pull-up resistor at the MCU input.
Thông tin tuân thủ
MAX174BCPI uses tin-lead (SnPb) finish and is non-RoHS. The MAX174BCPI+ variant is RoHS-compliant with matte-tin finish. AEC-Q100 not applicable (consumer/industrial part, 0-70°C). REACH compliance inferred from distributor declaration.
