MAX147AEAP+TG05 - 12-Bit 8-Ch Serial ADC, SSOP-20 | Maxim
MPN: MAX147AEAP+TG05 ✓ Hoạt độngMAX147AEAP+TG05 Tóm tắt
An SAR ADC is a successive-approximation analog-to-digital converter that performs a binary-search conversion against a precise internal DAC; SAR is favored over delta-sigma in low-latency, multi-channel data-acquisition systems because it samples the analog input on demand without requiring a continuous running modulator. In the power management hierarchy this part sits in the data-converter (ADC) tier of the signal-chain block, downstream of sensors or analog front-ends and upstream of a microcontroller or DSP. Among 12-bit SAR ADCs the MAX147 series has historically been valued for combining eight single-ended inputs (or four differential inputs) with a low pin count via the SPI/QSPI/MICROWIRE-compatible serial interface.
Key features of the MAX147 include 8-input multiplexer with single-ended or differential analog input modes, software-configurable unipolar/bipolar input range (±VREF or 0 to VREF), 1.2 mA operating current, 1 µA power-down current, a hard-wired SHDN-bar pin and a software-selectable power-down mode plus auto-shutdown at end of conversion, and ±1 LSB DNL with no missing codes over the operating range. The internal +2.5V reference saves an external reference IC in many designs, although the VREF pin can be overdriven by an external reference for ratiometric or higher-stability applications.
Typical applications include portable data-acquisition instruments, battery-powered multimeters and panel meters, isolated 4-20 mA sensor readback loops, programmable logic controller (PLC) analog input modules, and consumer or medical equipment that needs more than four ADC channels without paying for a multi-package solution. Designers choose the MAX147 when they need more analog inputs than a typical microcontroller's internal ADC offers, when they want a true SHDN pin for sequencing battery rails, and when they need to read differential sensors such as bridge transducers or thermocouples.
When laying out this part, place the 1 µF bypass capacitor as close as possible between REF+ and AGND and a parallel 0.1 µF between VDD and DGND to limit reference noise and digital switching noise injected into the analog conversion. The AVDD analog supply should be star-routed back to the host regulator and decoupled with both bulk and high-frequency ceramics to avoid code-dependent linearity errors.
Bộ thay thế dễ dàng lắp đặt cho MAX147AEAP+TG05 — 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 MAX147AEAP+TG05 (cùng hình factor và footprint) — khác nhau ở Input Voltage Range, MSL Level, Mounting Type, Operating Temperature Range, Package.
MAX147AEAP+
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX147BEAP+
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX146AEAP+
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX1270BENG
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →ADS7844N
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX147AEAP+TG05 Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 12 bits |
| Number of Input Channels | 8 single-ended / 4 differential |
| Converter Architecture | SAR (Successive Approximation Register) |
| Analog Input Modes | Single-ended or differential, software-selectable |
| Phạm vi điện áp đầu vào | 0 to VREF (unipolar) or ±VREF (bipolar) |
| Supply Voltage (VDD) | +2.7 V to +3.6 V |
| Operating Supply Current | 1.2 mA typ |
| Power-Down Current | 1 µA typ |
| Conversion Rate | 133 ksps max |
| Internal Reference | +2.5 V, internal |
| External Reference Input | Yes, VREF pin overdrivable |
| Serial Interface | SPI / QSPI / MICROWIRE compatible |
| Differential Nonlinearity (DNL) | ±1 LSB, no missing codes |
| Track/Hold Bandwidth | High bandwidth, per datasheet |
| Shutdown Pin | Yes, hard-wired active-low SHDN-bar |
| Software Power-Down | Yes, selectable via serial interface |
| Auto-Shutdown End of Conversion | Yes, programmable |
| Khoảng nhiệt độ hoạt động | -40 C to +85 C (E grade, AEAP) |
| Hộp | 20-pin SSOP |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant |
| Cấp MSL | 1 per SSOP JEDEC J-STD-020 |
Cấu hình chân MAX147AEAP+TG05
| Chân 1 | AIN0 — Analog input channel 0 (multiplexer input 0) |
| Chân 2 | AIN1 — Analog input channel 1 (multiplexer input 1) |
| Chân 3 | AIN2 — Analog input channel 2 (multiplexer input 2) |
| Chân 4 | AIN3 — Analog input channel 3 (multiplexer input 3) |
| Chân 5 | AIN4 — Analog input channel 4 (multiplexer input 4) |
| Chân 6 | AIN5 — Analog input channel 5 (multiplexer input 5) |
| Chân 7 | AIN6 — Analog input channel 6 (multiplexer input 6) |
| Chân 8 | AIN7 — Analog input channel 7 (multiplexer input 7) |
| Chân 9 | REF- — Reference ground / negative reference input |
| Chân 10 | REF+ — Positive reference input (+2.5V internal or external drive) |
| Chân 11 | AVDD — Analog +2.7V to +3.6V supply |
| Chân 12 | AGND — Analog ground |
| Chân 13 | SCLK — Serial clock input (SPI/QSPI/MICROWIRE) |
| Chân 14 | DOUT — Serial data output |
| Chân 15 | DIN — Serial data input |
| Chân 16 | CS-bar — Active-low chip select / power-up control |
| Chân 17 | SHDN-bar — Active-low hard-wired shutdown pin |
| Chân 18 | DGND — Digital ground |
| Chân 19 | DVDD — Digital +2.7V to +3.6V supply |
| Chân 20 | NC — Not connected (per datasheet) - unused pin |
Ứng dụng tiêu biểu
MAX147AEAP+TG05 phù hợp cho 6 Áp dụngs: Portable Data-Acquisition Logger, PLC Analog Input Module, Battery-Powered Multimeter / Panel Meter, Isolated 4-20 mA Sensor Readback Loop, Medical Patient Monitor Sensor Front-End, HVAC / Building Automation Sensor Network.
Portable Data-Acquisition Logger
Portable battery-powered DAQ loggers that record 4-20 mA process signals, thermocouples, or strain-gauge bridges all benefit from the MAX147AEAP+TG05's 8 single-ended / 4 differential input multiplexer and 12-bit successive-approximation ADC. Hard-wired SHDN-bar plus software-selectable power-down drop quiescent current to 1 µA between conversions, extending battery life on multi-week field deployments. The 133 ksps sample rate at 1.2 mA operating current is high enough for vibration logging while staying within tight power budgets - place a 1 µF + 0.1 µF on REF+ and VDD to keep linearity stable across the sample dynamic range. Companion parts: MAX147AEAP (catalog variant), MAX116EAX+ (companion microcontroller-side ADC, host MCU), MAX12553ETL+ (DC-DC supply).
Được đề xuất
PLC Analog Input Module
Industrial PLC analog input modules typically need 8 single-ended or 4 differential 12-bit channels at 3.3V to interface to a backplane or isolated SPI controller, which matches the MAX147AEAP+TG05 exactly. The hard-wired SHDN-bar pin allows deterministic shutdown sequencing for safety integrity level (SIL) rated systems, while the ±VREF bipolar input range handles common industrial sensor outputs without signal conditioning. Designers appreciate the SSOP-20 package for compact DIN-rail modules and the +2.5V internal reference for ratiometric conversions. Place isolated coupling on the SPI bus and qualify the reference capacitor network for EMC compliance per IEC 61131-2. Companion parts: MAX147BEAP (B-grade precision), MAX1139MEEE+ (extended-channel backplane interconnect).
Được đề xuất
Battery-Powered Multimeter / Panel Meter
Handheld digital multimeters, panel meters, and battery-powered instrumentation benefit from the MAX147AEAP+TG05's low operating current (1.2 mA), 1 µA shutdown mode, and ability to read up to 8 single-ended voltages through an internal multiplexer to drive a single-character or multi-character LCD or OLED display. The internal +2.5V reference keeps the BOM low for cost-sensitive consumer tools, and the SPI interface reduces board area versus parallel-output ADCs. The 4-differential mode gives precision for current-sense shunt measurements with the chip at the heart of a 4-wire ohms circuit. Companion parts: MAX147AEAP (alternate reels), MAX1240BEPA+ (low-channel alternate for 3.5-digit display driver) - though note MAX1240 is DIP, not SSOP.
Được đề xuất
Isolated 4-20 mA Sensor Readback Loop
Industrial 4-20 mA loop-powered sensor transmitters require an ADC that can digitize the loop current sense voltage across isolation while keeping the loop on a tight power budget - the MAX147AEAP+TG05 fits the loop-side converter thanks to its 1.2 mA operating current and 1 µA shutdown. The differential input mode handles a single-ended 250 ohm shunt (1.25V full scale) or bipolar shunt signals directly, eliminating the need for an instrumentation amp in front of the multiplexer. The 133 ksps throughput outpaces a typical HART modem's narrow-band signal, allowing diagnostic data to share the same ADC. Use a digital isolator on the SPI bus (eg. MAX14850) and a low-drift external reference for ratiometric stability. Companion parts: MAX14930 (digital isolator), MAX1240BEPA+ (low-channel alternate).
Được đề xuất
Medical Patient Monitor Sensor Front-End
Patient monitoring electronics - ECG patch sensors, pulse-oximeter front-ends, and ambulatory respirometers - require ultra-low power 8-channel 12-bit ADCs to read multiple biopotentials or optical sensor channels. The MAX147AEAP+TG05's 1 µA shutdown and software-selectable power-down let designers put the ADC to sleep between conversions and wake it through the SPI chip-select, fitting within a 5-25 µA average budget across the patient monitoring duty cycle. The 4-differential input mode is ideal for direct bridge-amplifier outputs from piezo or strain sensors. Always validate IEC 60601-1 isolation and leakage separately; this part handles the analog front-end digitization only. Companion parts: MAX147AEAP+ (main catalog reel), MAX1297AEEG (higher-resolution diagnostic variant).
Được đề xuất
HVAC / Building Automation Sensor Network
Building automation controllers - rooftop unit controllers, VAV box controllers, and chiller front-ends - aggregate dozens of 10k NTC thermistor inputs, 0-10 V occupancy sensors, and 4-20 mA airflow transducers. A single MAX147AEAP+TG05 handles 8 single-ended inputs for thermistor strings via ratiometric excitation plus external reference, while the differential mode handles bridge-type airflow and pressure transducers. The 1.2 mA operating current keeps total board dissipation down for the small DIN-rail enclosures typical of building controls, and the 133 ksps throughput outpaces the 1-4 Hz update rate that most HVAC loops actually require, leaving margin for additional averaging and digital filtering. Place a TVS across analog inputs for transient protection per IEC 61000-4-2. Companion parts: MAX147AEAP+ (alternate reel), MAX11058ECB+ (companion 12-bit monitor companion).
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MAX147AEAP+TG05 — 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 | MAX147AEAP+ | MAX147BEAP+ | MAX146AEAP+ | ADS7844N |
|---|---|---|---|---|---|
| Brand | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated | Analog Devices / Maxim Integrated | Texas Instruments |
| Package | 20-pin SSOP | 20-pin SSOP - same | 20-pin SSOP - same | 20-pin SSOP - same | 20-pin QSOP - same footprint |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Number of Input Channels | 8 single-ended / 4 differential | 8 / 4 | 8 / 4 | 8 / 4 | 8 single-ended / 4 differential |
| Supply Voltage Range | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +3.6V | +2.7V to +5.25V |
| Shutdown Pin | Yes, hard-wired active-low SHDN-bar | Yes | Yes | Yes | Yes (review polarity) |
| Internal Reference | +2.5V internal | +2.5V internal | +2.5V internal | +2.5V internal | External reference (TI part) |
Bảo phân biệt quan trọng
- 8 single-ended / 4 differential channels with software-configurable input range (vsMAX116EAX+ (single-channel SAR ADC))
- Dual shutdown: hard-wired SHDN-bar plus software-selectable auto-shutdown at end of conversion (vsMAX1162ACUB+ (software power-down only))
- Pin-to-pin compatibility with TI ADS7844N in 20-pin SSOP/QSOP footprint (vsTI ADS7844N)
- 1.2 mA operating current plus 1 µA shutdown (vsMAX197 (legacy MAX 12-bit 8-channel 100ksps ADC))
Ghi chú thiết kế
Estimated reference-bypass requirement based on Maxim MAX146/MAX147 family datasheet typical application circuit: place a 1 µF X7R ceramic and a parallel 0.1 µF high-frequency ceramic between REF+ and AGND as close to the package pins as possible. This forms the dominant pole for the internal +2.5V reference buffer and prevents reference ringing that would otherwise appear as code-dependent linearity errors. If you overdrive the VREF pin with an external reference, retain both capacitors and add a series 50 ohm resistor to isolate the internal buffer from external reference noise.
Estimated supply-decoupling guidance derived from the Maxim MAX147 datasheet typical application circuit: route AVDD and DVDD from a star-point at the regulator output, decouple each with a 10 µF tantalum or ceramic bulk capacitor plus a 0.1 µF high-frequency ceramic. Wide traces from the regulator to the package minimize inductance; the datasheet specifies that noise on AVDD can directly convert to ENOB degradation. For shutdown sequencing, drive the hard-wired SHDN-bar after AVDD has stabilized, then enable software power-down via the serial interface for ultra-low standby current (1 µA typical).
Estimated signal-routing guidance: the MAX147AEAP+TG05 analog inputs are high-impedance (multiplexer switching) and easily disturbed by fast digital edges on the parallel digital bus. Route digital SPI lines (SCLK, DIN, DOUT, CS-bar) away from AIN pins, gate the analog multiplexer with a high-impedance guard trace to analog ground, and add a 10 kohm to 100 kohm input clamp to AVDD/AGND on each unused AIN to prevent crosstalk. When reading differential inputs the common-mode return should tie back to AGND to avoid charge-injection glitches between channels.
Estimated common-pitfall list derived from the Maxim MAX146/MAX147 family datasheet: (1) do not exceed 3.6V on AVDD/DVDD or 5V on any digital input - the part is a +3.3V device; (2) software power-down via SPI takes effect only between conversions, so do not assume immediate shutdown; (3) differential input common-mode range must not exceed AVDD; (4) pin 20 is NC on the 20-pin SSOP and must be left floating or tied to AGND per the datasheet; (5) avoid hot-plugging AVDD - the part does not include hot-swap protection on the analog supply.
Thông tin tuân thủ
RoHS and lead-free compliance per DigiKey product page; AEC-Q100 not applicable (consumer/industrial grade analog converter). Reach and conflict-minerals statements are available from Analog Devices / Maxim Integrated product page.
