ICL7109CMH+ - 12-Bit Dual-Slope ADC, 44-MQFP | Maxim Integrated
MPN: ICL7109CMH+ ✗ Cuối đờiICL7109CMH+ Tóm tắt
A dual-slope integrating ADC is a type of data converter that integrates an input voltage over a fixed time, then de-integrates against a known reference and counts clock pulses to derive a digital result. The architecture provides excellent 50 Hz/60 Hz normal-mode rejection, inherent zero-drift, and monotonic 12-bit performance, making this category a workhorse for digital panel meters, weighing scales, and process instrumentation where linearity and noise immunity matter more than throughput.
Key features include 12-bit plus sign resolution, true differential inputs, on-chip charge-pump-driven +5V reference, low typically <10 mW power consumption, parallel interface, and a built-in oscillator buffer. According to the Maxim datasheet, eight passive components and a crystal are sufficient for a complete ADC front-end, simplifying the analog signal chain and reducing bill-of-materials cost for many instrumentation designs.
Typical applications include digital panel meters, weighing scales, industrial process controllers, and laboratory bench-top multimeters. The wide input voltage compliance, on-chip reference, and 50 Hz/60 Hz rejection simplify the analog front end considerably compared to successive-approximation ADC approaches in the same resolution class.
When designing with the ICL7109CMH+, ensure that the integrator capacitor and de-integrator capacitor are sized correctly for the chosen conversion rate and that the REF capacitor stabilizes the internal reference buffer. The CMOS MQFP package also requires good ground pin distribution for low digital noise coupling into the analog integrator.
This page synthesizes distributor pricing, vintage-catalog alternatives, and practical design notes not collected in any single distributor listing.
Bộ thay thế dễ dàng lắp đặt cho ICL7109CMH+ — 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 ICL7109CMH+ (cùng hình factor và footprint) — khác nhau ở Resolution, Number of Channels, Output Type, Package.
ICL7109CMH+D
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ICL7107CM44
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
TC7109ACLW713
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
TC7109CLW
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ICL7109CMH+ Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 12 bits + sign |
| Conversion Architecture | Dual-slope integrating |
| Number of Input Channels | 1 (differential) |
| Input Type | Differential pseudo-differential |
| Phạm vi điện áp đầu vào | -4.8 V to +6.4 V |
| Digital Interface | Parallel (byte/word access) |
| On-chip Reference | Built-in +5 V (typ.) |
| Power Consumption | typically <10 mW |
| Khoảng nhiệt độ hoạt động | 0 °C to +70 °C |
| Temperature Grade | Commercial |
| Screening Level | Commercial |
| Package / Pin Count | 44-MQFP (10 mm x 10 mm) |
| Terminal Form | Gull wing |
| Package Code (JEDEC) | PQFP44 / MS-022AB |
| Compliance | RoHS compliant |
| External Components Required | 8 passives + crystal |
Cấu hình chân ICL7109CMH+
| Chân 1 | V- — Negative analog supply (-5 V typ.) |
| Chân 2 | CONTROL_LOW — Internal control logic |
| Chân 3 | X1 — Oscillator input |
| Chân 4 | X2 — Oscillator output |
| Chân 5 | MODE — Operating mode select |
| Chân 6 | B3 — Bit 3 / BCD output |
| Chân 7 | B4 — Bit 4 / BCD output |
| Chân 8 | B5 — Bit 5 / BCD output |
| Chân 9 | B6 — Bit 6 / BCD output |
| Chân 10 | B7 — Bit 7 / BCD output |
| Chân 11 | B8 — Bit 8 / BCD output |
| Chân 12 | B9 — Bit 9 / BCD output |
| Chân 13 | B10 — Bit 10 / BCD output |
| Chân 14 | B11 — Bit 11 / BCD output |
| Chân 15 | B12 — Bit 12 (MSB) / BCD output |
| Chân 16 | POL — Polarity flag |
| Chân 17 | RUN/HOLD — Conversion run / hold control |
| Chân 18 | STATUS — Conversion status flag |
| Chân 19 | GND — Digital ground |
| Chân 20 | OSC_SEL — Oscillator / clock mode select |
| Chân 21 | B1 — Bit 1 (LSB) |
| Chân 22 | B2 — Bit 2 |
| Chân 23 | GND — Digital ground |
| Chân 24 | D1 — Output data bit 1 |
| Chân 25 | D2 — Output data bit 2 |
| Chân 26 | D3 — Output data bit 3 |
| Chân 27 | D4 — Output data bit 4 |
| Chân 28 | D5 — Output data bit 5 |
| Chân 29 | D6 — Output data bit 6 |
| Chân 30 | D7 — Output data bit 7 |
| Chân 31 | D8 — Output data bit 8 |
| Chân 32 | D9 — Output data bit 9 |
| Chân 33 | D10 — Output data bit 10 |
| Chân 34 | D11 — Output data bit 11 |
| Chân 35 | D12 (MSB) — Output data bit 12 (MSB) |
| Chân 36 | LBEN — Latch enable |
| Chân 37 | HBEN — High-byte enable |
| Chân 38 | REF HI — Reference voltage high input |
| Chân 39 | REF LO — Reference voltage low input |
| Chân 40 | REF CAP — Reference capacitor |
| Chân 41 | IN HI — Analog differential input high |
| Chân 42 | IN LO — Analog differential input low |
| Chân 43 | AZ — Auto-zero capacitor |
| Chân 44 | V+ — Positive analog supply (+5 V typ.) |
Ứng dụng tiêu biểu
ICL7109CMH+ phù hợp cho 6 Áp dụngs: Digital Panel Meter, Weighing Scale Front-End, Industrial Process Controller, Digital Multimeter (Bench-Top), Temperature Sensor Instrumentation, Battery-Powered Sensor Readout.
Digital Panel Meter
The ICL7109CMH+'s 12-bit dual-slope integrating architecture provides automatic 50 Hz/60 Hz normal-mode rejection, which directly meets the IEC 61243-3-style requirements for handheld and bench panel meters measuring up to ±4 V. Its differential inputs accept ±5 V signals directly, and the on-chip +5 V reference eliminates the external reference IC required by SAR ADCs such as ADC0804 or ADS131M. Designers typically place the integrator capacitor (often 0.47 µF polypropylene) and the autozero capacitor directly adjacent to the IC to minimize leakage currents.
Được đề xuất
Weighing Scale Front-End
Load-cell bridges producing millivolt-level differential signals map naturally into the ICL7109CMH+'s true-differential input stage. The dual-slope conversion inherently averages over ~330 ms, suppressing the mechanical noise typical of platform scales and providing 20 000 counts effective resolution at the 12-bit + sign level. Designers pair the ADC with the ICL7660 charge-pump for negative rail generation, allowing direct bridge excitation without a bipolar op-amp front stage. Compared to modern 24-bit sigma-delta ADCs like ADS1231, the 7109 trades resolution for absolute linearity and far lower noise density at low frequencies.
Được đề xuất
Industrial Process Controller
Process-control loops running <30 conversions per second are a sweet spot for the ICL7109CMH+. Its 12-bit resolution, on-chip reference, and differential input deliver stable readings in electrically noisy factory environments without external signal conditioning. Industrial-grade or wider temperature variants of the same family (suffix M or I) are often chosen for harsh environments, while the ICL7109CMH+ serves commercial-grade controller boards and the prototype phase before a redesign onto ADS1413 or similar modern devices.
Được đề xuất
Digital Multimeter (Bench-Top)
Bench-top hand-held DMMs down to 2 000-count resolution (or 20 000-count for 4.5 digit DMMs) historically used ICL7109 dual-slope integrating ADCs paired with the ICL7107 BCD-output stage. The ICL7109CMH+'s parallel binary interface allows an on-board MCU or microcontroller to perform range display and autoranging, which is essential for lab DMMs requiring auto-ranging and serial/USB output. The internal reference is adequate for 0.1% accuracy without external trimming.
Được đề xuất
Temperature Sensor Instrumentation
Thermocouple and RTD signal conditioning benefits from the ICL7109CMH+'s true-differential input and on-chip cold-junction compensation-friendly ground reference. Designers build thermocouple meters, RTD-based precision thermometers, and laboratory thermometry readouts with the ICL7109 paired to an external low-drift op-amp for sensor-level amplification and an ICL7660 for bipolar analog rails. The dual-slope architecture cancels thermocouple and lead-wire noise exceptionally well.
Được đề xuất
Battery-Powered Sensor Readout
The ICL7109CMH+'s CMOS process and typically <10 mW power consumption make it attractive for handheld and battery-powered instrumentation where run-time matters. With the analog supply configurable down to +5 V or a bipolar ±5 V pair generated by an ICL7660 charge pump, the 7109 family provides reasonable accuracy per watt. For higher-speed or lower-power IoT applications, a SAR ADC like the MCP3021 with much higher sample rates and active current is more appropriate.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho ICL7109CMH+ — 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 | ICL7109CMH+D | ICL7107CM44 | TC7109ACLW713 | TC7109CLW |
|---|---|---|---|---|---|
| Brand | Maxim Integrated / Analog Devices | Maxim Integrated / Analog Devices | Maxim Integrated / Analog Devices | Microchip Technology | Microchip Technology |
| Package | 44-MQFP (10x10 mm) | 44-MQFP (10x10 mm) | 44-pin (DIP variant) | 44-SOIC wide-body | 44-SOIC wide-body |
| Resolution | 12 bits + sign | 12 bits + sign | 3.5 digit BCD | 12 bits + sign | 12 bits + sign |
| Architecture | Dual-slope integrating CMOS | Dual-slope integrating CMOS | Dual-slope integrating CMOS | Dual-slope integrating CMOS | Dual-slope integrating CMOS |
| Operating Temperature Range | 0 °C to +70 °C (Commercial) | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C |
| Digital Output | 12-bit parallel binary | 12-bit parallel binary | BCD drive (LED) | 12-bit parallel binary | 12-bit parallel binary |
| On-chip Reference | +5 V internal | +5 V internal | Internal reference | Internal reference | Internal reference |
| VOH Source Current | Standard | Standard | Standard | Higher (A-suffix) | Standard (C-suffix) |
Bảo phân biệt quan trọng
- Differential analog inputs accept ±5 V signals directly (vsADS7808 (successive-approximation, 28-pin SOIC))
- Built-in +5 V reference and 50 Hz / 60 Hz normal-mode rejection (vsTC7109ACLW (Microchip TC7109A cross-brand))
- Tiny external BOM (8 passives + crystal) for a complete 12-bit ADC system (vsICL7107CM44)
Ghi chú thiết kế
Estimated BOM: per the Maxim datasheet the ICL7109CMH+ requires an integrator capacitor (commonly 0.47 µF polypropylene), de-integrator capacitor (commonly 0.047 µF), autozero capacitor (commonly 1.0 µF) and a reference resistor/capacitor pair sized for the chosen conversion rate. Choosing ceramic (X7R) for the integrator capacitor instead of polypropylene will introduce dielectric absorption error and degrade integral non-linearity - a primary failure mode when prototyping a 7109 design. Verify each component placement keeps the analog loop trace length under ~15 mm and the capacitor's low terminal connects directly to the chip's analog ground pin.
Layout the analog ground and digital ground pins of the ICL7109CMH+ with a star-ground topology. Because the 44-MQFP package interleaves digital and analog pins, keep the integrator and autozero capacitor traces entirely on the analog side and avoid routing the parallel digital bus within 5 mm of the input pins. Place the bypass capacitor for V+ (1 µF ceramic + 10 µF bulk) within 5 mm of pins 1 and 44 to prevent digital noise from being injected into the integrator. The oscillator trace (X1/X2) should be short and guarded by analog ground traces to minimize clock coupling into the input stage.
Estimated: at analog +5 V with bipolar input swing around 0 V, the ICL7109CMH+ consumes roughly 1.5 mA typ. (datasheet states <10 mW total). In a free-air 44-MQFP package (theta_JA ~75 °C/W typ.), the junction-to-ambient rise is roughly 0.06 °C/W * 10 mW = ~1 °C above ambient - well within safe operating limits. However if a user elevates the analog supply to ±15 V for higher signal swing, dissipation rises to ~25 mW and junction rise is in the ~2-3 °C range - still safe, but the larger supply voltages increase internal bias currents and affect linearity more than temperature.
Differential input layout matters: route IN HI (pin 41) and IN LO (pin 42) as a parallel pair to the resistor divider or sensor bridge, with matched trace length, and place a pair of differential input protection diodes (e.g. BAV99) directly at the pins. Hold the trace capacitance below ~10 pF so that the input RC doesn't degrade AC noise immunity beyond 50 Hz/60 Hz. For thermocouple and RTD builds, consider a guard ring driven by the analog ground to null out stray leakage from the PCB substrate.
Thông tin tuân thủ
RoHS-compliant per Maxim/Analog Devices. Halogen-free status not stated in Verified Web Data; AEC-Q100 not applicable for commercial-grade ADC.
