MAX1393MTB+T - 12-Bit 312.5ksps SAR ADC | Maxim Integrated
MPN: MAX1393MTB+T ✓ Hoạt độngMAX1393MTB+T Tóm tắt
An SAR ADC is a successive-approximation-register converter that performs a binary search against the analog signal using an internal DAC and comparator. Each conversion completes in one cycle of the internal clock, producing a deterministic latency and no pipeline delay. SAR ADCs occupy a unique position in the data-converter hierarchy: they sit between sigma-delta (highest resolution, lowest speed) and flash (lowest resolution, highest speed) converters, offering 8-18 bit resolution at 100 ksps to multi-msps sampling rates with very low active power. This makes them the default choice for multiplexed multi-channel low-frequency precision sampling.
Key features of the MAX1393MTB+T include 312.5 ksps throughput, true-differential or 2-channel single-ended input multiplexer, automatic shutdown between conversions for extended battery life, and an external reference up to AVDD. The device also integrates a high-bandwidth track-and-hold and a serial interface that supports daisy-chaining of multiple ADCs on a single SPI bus.
Architecturally, the MAX1393 uses a capacitive-charge-redistribution DAC array driven by an internal oscillator, with a single-supply LDO generating the internal core rail. The shutdown current is specified in the nanoampere range, allowing duty-cycled sampling for handheld instruments where the ADC wakes, converts, and re-enters shutdown on every host interrupt.
Typical applications include portable medical instrumentation (blood-glucose meters, pulse oximeters), 4-20 mA industrial loop transmitters, handheld multimeters, battery fuel-gauges, and sensor-interface front-ends. The wide 1.5 V to 3.6 V supply range supports direct connection to single-cell Li-ion, two-cell alkaline, or 3.3 V digital rails without level shifting.
When designing with this part, place the 1 µF AVDD bypass capacitor within 3 mm of the supply pin and keep the analog ground return separate from the digital switching return. Drive CNVST with a clean rising edge from a low-jitter timer or GPIO to minimize aperture uncertainty, especially when digitizing small signals near the 12-bit LSB threshold.
Bộ thay thế dễ dàng lắp đặt cho MAX1393MTB+T — 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 MAX1393MTB+T (cùng hình factor và footprint) — khác nhau ở Package, Number of Channels, Resolution, Input Type, Operating Temperature.
MAX1396MTB+T
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →MAX11120ATI+T
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →MAX11164ETC+T
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →MAX1119EKA-T
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →MAX1115EKA+G002
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →MAX1393MTB+T Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 12 bits |
| Architecture | SAR (Successive Approximation Register) |
| Tỷ lệ lấy mẫu | 312.5 ksps |
| Number of Channels | 1 differential / 2 single-ended (input mux) |
| Điện áp cung cấp | 1.5 V to 3.6 V (single supply) |
| Input Type | True differential or single-ended |
| Reference Type | External (up to AVDD) |
| Giao diện | SPI / QSPI / MICROWIRE-compatible, 3-wire serial |
| Nhiệt độ hoạt động | -40 °C to +85 °C (industrial) |
| Hộp | 10-pin TDFN-EP (3 mm × 3 mm) |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant |
| Lead-Free | Yes |
Cấu hình chân MAX1393MTB+T
| Chân 1 | AIN+ — Positive analog input (differential) / input 1 (single-ended) |
| Chân 2 | AIN- — Negative analog input (differential) / input 2 (single-ended) |
| Chân 3 | REF — External reference voltage input |
| Chân 4 | AVDD — Analog supply voltage (1.5 V to 3.6 V) |
| Chân 5 | GND — Analog ground |
| Chân 6 | CNVST — Active-low conversion start input |
| Chân 7 | DIN — Serial data input (for daisy-chain mode) |
| Chân 8 | SCLK — Serial clock input |
| Chân 9 | DOUT — Serial data output |
| Chân 10 | EP — Exposed thermal pad (tie to GND ground plane) |
Ứng dụng tiêu biểu
MAX1393MTB+T phù hợp cho 6 Áp dụngs: Portable Medical Instrumentation, 4-20 mA Industrial Loop Transmitter, Handheld Digital Multimeter, Battery Fuel Gauge and Battery Monitoring, Sensor Interface Front-End (Thermocouple / RTD / Bridge), Data-Acquisition Modules and PLC Analog Inputs.
Portable Medical Instrumentation
The MAX1393MTB+T fits handheld medical devices such as blood-glucose meters, pulse oximeters, and patient thermometers where 12-bit resolution at 312.5 ksps is sufficient for sensor signal conditioning. The 1.5 V to 3.6 V supply supports direct connection to a single-cell Li-ion or two-cell alkaline battery, and the automatic shutdown between conversions drops standby current to the nanoampere range to extend battery life across multi-month replacement cycles. Placed between the sensor front-end and the MCU's SPI bus, it samples once on a CNVST pulse and reports the conversion over the 3-wire SPI; disease site can be daisy-chained with multiple MAX1396 devices for synchronized multi-site sampling without an external analog switch.
Được đề xuất
4-20 mA Industrial Loop Transmitter
The MAX1393MTB+T digitizes the loop-current sense resistor in a 4-20 mA smart transmitter, converting the analog process variable to a 12-bit digital code for the loop microcontroller. Its true-differential input stage rejects common-mode noise from long field wiring, and the 312.5 ksps throughput allows >100 Hz update rates with margin for digital filtering. Positioned between the sense resistor and the MCU SPI master, it operates from the loop's 24 V bus stepped down to 3.3 V; the fire site benefits from <1 mA active current, leaving the bulk of the 4 mA loop budget for the sensor itself without violating the HART (hardware-addressable remote transducer) protocol's low-current requirement.
Được đề xuất
Handheld Digital Multimeter
The MAX1393MTB+T serves as the measurement ADC in a handheld DMM, digitizing the auto-ranging shunt or voltage-divider output across multiple ranges. Its true-differential input accepts both polarities without an input-polarity-reversal switch, and the 12-bit resolution gives 4096 counts - sufficient for a 3½-digit display plus autoranging headroom. Mounted adjacent to the range-switch relay bank with a 1 µF AVDD bypass cap, it samples once per measurement cycle and enters shutdown between conversions; fire site is reduced for short time during each autorange dwell, while standby current draws negligible power from the 9 V battery.
Được đề xuất
Battery Fuel Gauge and Battery Monitoring
The MAX1393MTB+T monitors cell voltage and current in single-cell Li-ion battery packs where its 1.5 V minimum supply allows direct connection to the cell itself without a boost converter. The 2-channel single-ended mux digitizes both the pack voltage and the sense-resistor current simultaneously, supporting coulomb-counting fuel-gauging algorithms. Placed across the sense resistor with differential-mode sampling, it provides 12-bit accuracy on a ±1 A sense range; fire site is in the protection circuit module (PCM), sharing the same ground reference as the protection FETs to avoid ground-loop errors in the digitized voltage and current samples.
Được đề xuất
Sensor Interface Front-End (Thermocouple / RTD / Bridge)
The MAX1393MTB+T digitizes low-level analog signals from thermocouples, RTDs, and strain-gauge bridges in industrial sensor modules, where its true-differential input rejects common-mode pickup from motor drives and 50/60 Hz mains. Its 312.5 ksps throughput supports software-oversampling averaging for effective resolution beyond 12 bits in low-bandwidth temperature measurements. Mounted at the output of the instrumentation-amp front-end with a low-TC external reference, it provides ratiometric conversion; fire site is the sensor module so terminated to the same analog ground plane as the bridge excitation source for proper ratiometric conversion in the digitized bridge output.
Được đề xuất
Data-Acquisition Modules and PLC Analog Inputs
The MAX1393MTB+T serves as a per-channel ADC in modular data-acquisition systems and PLC analog-input cards where compact 10-pin TDFN packaging allows high channel density. Its SPI interface supports daisy-chaining multiple devices on a single chip-select, allowing 8-16 channels of synchronized sampling from one MCU SPI peripheral. Placed adjacent to each channel's input-protection TVS and filter network, it samples on a low-jitter timer interrupt and reports conversions to the PLC backplane; fire site is the analog-input module, with thermal-pad groundings to the analog ground plane for low-impedance analog reference and reduced digital switching noise coupling into the digitized signal.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MAX1393MTB+T — 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 | MAX1396MTB+T | MAX11120ATI+T | MAX11164ETC+T | MAX1119EKA-T | MAX1115EKA+G002 |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 10-pin TDFN-EP (3x3 mm) | 10-pin TDFN-EP (3x3 mm) - same | 10-pin TDFN-EP - same | 10-pin TDFN-EP - same | 10-pin TDFN-EP - same | 10-pin TDFN-EP - same |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Interface | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI | SPI | SPI | SPI |
| Automatic Shutdown | Yes | Yes | Yes | Yes | Yes | Yes |
Bảo phân biệt quan trọng
- Automatic shutdown with fast wake-up between conversions (vsMAX1119EKA-T)
- True-differential input architecture (vsMAX11164ETC+T)
- Daisy-chain-capable SPI interface (vsMAX11120ATI+T)
Ghi chú thiết kế
Place a 1 µF X7R ceramic bypass capacitor as close as possible (within 3 mm) to the AVDD pin with a short, wide trace to the analog ground plane. A 0.1 µF capacitor in parallel improves noise suppression above 10 MHz. For battery applications, the AVDD trace should be star-routed from the battery with no other high-current devices on the same trace to avoid load-transient coupling into the reference voltage.
Solder the exposed thermal pad (EP) to a continuous analog ground plane for both thermal dissipation and low-impedance grounding of the internal reference. Separate analog and digital ground returns and join them at a single point under the IC. Keep the analog input traces short and guarded by a ground trace on either side to reduce common-mode pickup from SPI/CLK edges.
Drive CNVST with a clean, low-jitter rising edge (jitter <50 ps RMS) from a hardware timer or a dedicated GPIO to minimize sampling-aperture uncertainty. Avoid routing CNVST near switching sources, or use a series resistor at the source to damp ringing. Keep the SPI traces (SCLK, DOUT, DIN) short and length-matched if daisy-chaining multiple ADCs on the same bus to avoid setup/hold violations.
Do not exceed AVDD on the REF input or on AIN+/AIN-; absolute maximum ratings apply. Do not omit the REF bypass capacitor (typically 0.1 µF to 1 µF) - omitting it injects reference noise into the conversion. When operating in single-ended mode, tie AIN- to analog ground rather than leaving it floating to prevent charge injection from the internal mux switching.
Thông tin tuân thủ
RoHS compliant per Maxim Integrated product page. Operating temperature -40C to +85C is industrial-grade, not AEC-Q100 automotive qualified.
