ICL7109CMH+D - 12-Bit Dual-Slope ADC, 44-MQFP | Maxim Integrated
MPN: ICL7109CMH+D ✗ انتهى عمره الإنتاجيICL7109CMH+D نظرة عامة
An integrating ADC (also called a dual-slope ADC) is a class of analog-to-digital converter that converts an analog input voltage into a digital representation by integrating the input over a fixed time window and then measuring the time required to de-integrate against a known reference. Within the broader ADC taxonomy, the integrating type sits between successive-approximation-register (SAR) ADCs and sigma-delta ADCs; it offers excellent rejection of mains-frequency noise, inherent input integration (noise averaging), and differential input capability, at the cost of lower conversion rate (typically a few conversions per second to a few hundred).
The ICL7109 delivers ±0.5 LSB (typical) integral non-linearity, on-chip differential input stage accepting ±4.2V common-mode range, true differential inputs and differential reference, and TTL-compatible 3-state outputs that interface directly to microprocessors. The part operates from ±5V supplies, consumes under 30 mW, and provides a BYTE/HBENA strobe for simplified 8-bit bus interface.
Typical applications include digital panel meters, digital multimeters (DMMs), process controllers, weigh scales, and any precision low-frequency measurement where 50 Hz/60 Hz normal-mode rejection and differential inputs are critical. Its differential reference input also enables ratiometric measurement such as bridge-style transducers.
When designing with this part, follow the manufacturer datasheet's recommended RC component values to achieve the specified conversion speed and noise rejection. Select INTVREF cap and integrator cap with low-dielectric-absorption (C0G/NP0) ceramics or film capacitors to avoid integral non-linearity degradation. Use a clean, low-ripple ±V supply with star-ground layout, as the analog and digital grounds should be joined only at the IC's GND pin.
بدائل مباشرة لـ ICL7109CMH+D — نفس الحزمة، متوافق دبوس بدبوس. تُستثنى القطع ذات الحزم المختلفة التي تتطلب تعديل PCB.
الطرازات في هذه السلسلة
طرازات من نفس السلسلة متوافقة تمامًا مع ICL7109CMH+D (نفس عامل الشكل والبصمة) — يختلف في Resolution.
ICL7109CPL+
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
TC7109ACPL
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
ICL7109CMH+D الحدود القصوى والخصائص الكهربائية
| الدقة | 12 bit + sign |
| Architecture | Dual-slope integrating |
| Number of Channels | 1 |
| Conversion Method | Dual Slope |
| نطاق جهد الدخل | -4.8 V to +6.4 V |
| جهد التغذية | ±5 V (dual supply) |
| درجة حرارة التشغيل | 0 C to +70 C |
| Screening Level | Commercial |
| نوع الخرج | 3-state binary, TTL-compatible |
| Output Format | Parallel, word access |
| الواجهة | Byte/HBEN strobe, microprocessor-compatible |
| نوع التركيب | Surface Mount |
| العلبة | MQFP-44 (10x10 mm, 2 mm pitch) |
| عدد الأطراف | 44 |
| حالة RoHS | Compliant |
| Lead-Free | Yes (suffix +D) |
| Differential Inputs | Yes (INHI/INLO pair) |
تكوين أطراف ICL7109CMH+D
| دبوس 1 | INLO — Differential analog input low |
| دبوس 2 | INHI — Differential analog input high |
| دبوس 3 | REFLO — Reference voltage low |
| دبوس 4 | REFHI — Reference voltage high |
| دبوس 5 | COMMON — Analog common (typically GND) |
| دبوس 6 | CREF+ — Reference capacitor positive |
| دبوس 7 | CREF- — Reference capacitor negative |
| دبوس 8 | INT — Integrator output |
| دبوس 9 | CINT — Integrator capacitor connection |
| دبوس 10 | BUFFER — Integrator buffer output |
| دبوس 11 | C AZ — Auto-zero capacitor |
| دبوس 12 | A Z — Auto-zero node |
| دبوس 13 | V+ — Positive supply (+5V) |
| دبوس 14 | GND — Digital ground |
| دبوس 15 | OSC SEL — Oscillator select |
| دبوس 16 | OSC OUT — Oscillator output |
| دبوس 17 | OSC IN — Oscillator input |
| دبوس 18 | RUN/HOLD — Conversion run / hold control |
| دبوس 19 | STATUS — Conversion status output |
| دبوس 20 | POL — Polarity output (sign bit) |
| دبوس 21 | OR — Out-of-range flag |
| دبوس 22 | B12 — Bit 12 (MSB) output |
| دبوس 23 | B11 — Bit 11 output |
| دبوس 24 | B10 — Bit 10 output |
| دبوس 25 | B9 — Bit 9 output |
| دبوس 26 | B8 — Bit 8 output |
| دبوس 27 | B7 — Bit 7 output |
| دبوس 28 | B6 — Bit 6 output |
| دبوس 29 | B5 — Bit 5 output |
| دبوس 30 | B4 — Bit 4 output |
| دبوس 31 | B3 — Bit 3 output |
| دبوس 32 | B2 — Bit 2 output |
| دبوس 33 | B1 — Bit 1 (LSB) output |
| دبوس 34 | CE — Chip enable (3-state control) |
| دبوس 35 | BYTE/HBENA — Byte / high-byte enable strobe |
| دبوس 36 | TEST — Factory test pin (leave open or GND) |
| دبوس 37 | V- — Negative supply (-5V) |
| دبوس 38 | NC — Not connected (per datasheet) |
| دبوس 39 | NC — Not connected (per datasheet) |
| دبوس 40 | NC — Not connected (per datasheet) |
| دبوس 41 | NC — Not connected (per datasheet) |
| دبوس 42 | NC — Not connected (per datasheet) |
| دبوس 43 | NC — Not connected (per datasheet) |
| دبوس 44 | NC — Not connected (per datasheet) |
التطبيقات النموذجية
ICL7109CMH+D مناسب لـ 6 التطبيقs: Digital Panel Meter, Digital Multimeter (DMM), Weigh Scale and Load Cell, Process Controller and Industrial Measurement, Temperature Measurement Bridge (Thermocouple Cold-Junction Compensation), pH and Electrochemical Sensor Interface.
Digital Panel Meter
The ICL7109CMH+D's 12-bit plus sign dual-slope integrating architecture and ±4.8 V to +6.4 V differential input range make it ideal for 3.5-digit and 4.5-digit digital panel meters. Placed between a high-impedance input divider and a 7-segment driver chain, the part inherently rejects 50 Hz / 60 Hz mains-frequency noise without external filtering, achieving ±0.5 LSB integral non-linearity according to the manufacturer datasheet. Unlike a SAR ADC, the integrating core averages mains noise over the integration window so a DMM reading stays stable on noisy factory floors. Recommended companion parts: ICL8069 (precision 1.2V reference), CD4054 (7-segment LCD driver), HCPL-7800 (isolated amplifier).
موصى به
Digital Multimeter (DMM)
The ICL7109CMH+D is widely used in handheld digital multimeters because the dual-slope integrating core provides true differential inputs for direct voltage measurements plus built-in 50 Hz / 60 Hz normal-mode rejection. According to the manufacturer datasheet, the part accepts differential inputs up to ±4.8 V common-mode and produces a parallel binary word readable by any 8-bit microcontroller. Placed between the input divider / current-shunt resistor and the display driver, it gives a 12-bit signed reading accurate to 0.01 percent. The MQFP-44 surface-mount package suits compact handheld PCB layouts. Recommended companion parts: TL431ACDBZR (shunt reference), CS5330A-KSZ (current-sense amp).
موصى به
Weigh Scale and Load Cell
The ICL7109CMH+D's differential inputs and low-noise integrating core make it ideal for strain-gauge load cell scales and weigh bridges. A typical circuit uses a 350 ohm bridge excited by 5V, with the differential output fed to the ICL7109CMH+D's INHI / INLO inputs. The dual-slope conversion rejects the bridge-excitation ripple, achieving a stable 12-bit reading in noisy industrial environments. According to the manufacturer datasheet, the part's 3-state parallel output interfaces directly to a microcontroller for tare / calibration storage. Recommended companion parts: ADS1231 (24-bit sigma-delta for higher precision), INA125 (bridge amplifier).
موصى به
Process Controller and Industrial Measurement
The ICL7109CMH+D suits 4-20 mA process controller loops and slow industrial measurement channels where 12-bit resolution and 50 Hz / 60 Hz rejection matter more than conversion speed. According to the manufacturer datasheet, the part's differential inputs accept ±4.8 V common-mode, allowing direct connection to a current-sense shunt returning a ground-referenced process variable. The MQFP-44 package is rated for 0 C to +70 C commercial industrial environments, and the parallel binary output streamlines interface to a microcontroller front panel. Recommended companion parts: ADS1100A7IDBVRG4 (16-bit I2C ADC for higher precision channels).
موصى به
Temperature Measurement Bridge (Thermocouple Cold-Junction Compensation)
The ICL7109CMH+D integrates the differential thermocouple EMF into a digital reading with built-in 50 Hz / 60 Hz line-noise rejection. Placed between a precision thermocouple amplifier and the microcontroller, the part delivers ±0.5 LSB integral non-linearity across the full -4.8 V to +6.4 V input range. According to the manufacturer datasheet, the differential reference input also enables ratiometric cold-junction compensation by tying the reference to a silicon-diode-sensed junction temperature. Recommended companion parts: ADS1110A3IDBVRG4 (16-bit I2C ADC for cold-junction IC temperature).
موصى به
pH and Electrochemical Sensor Interface
The ICL7109CMH+D suits pH meters, dissolved-oxygen probes, and other high-impedance electrochemical sensors because its input stage has very low bias current and differential inputs handle the high-impedance probe reference. According to the manufacturer datasheet, integrating the probe voltage over a fixed window averages sensor noise and mains pickup, yielding a stable 12-bit signed reading. Placed between a pH-amplifier buffer and a microcontroller, the ICL7109CMH+D offers an inexpensive, robust ADC for laboratory and field instruments. Recommended companion parts: AD8628 (precision op-amp for pH buffer), ADS1100A7IDBVRG4 (auxiliary reference ADC).
موصى به
ملخص المنتجات الموصى بها
بيانات مرجعية هندسية لـ ICL7109CMH+D — المقارنة وإرشادات التصميم ومعلومات الامتثال.
دليل الاختيار
المقارنة مع البدائل
| المعامل | هذا المنتج | ICL7109CPL+ | TC7109ACPL |
|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Microchip Technology |
| Package | MQFP-44 (10x10 mm) | PDIP-40 (DIP-40) - NOT pin-compatible | PDIP-40 (DIP-40) - NOT pin-compatible |
| Resolution | 12 bit + sign | 12 bit + sign | 12 bit + sign |
| Architecture | Dual-slope integrating | Dual-slope integrating | Dual-slope integrating |
| Supply Voltage | ±5 V | ±5 V | ±5 V |
| Input Voltage Range | -4.8 V to +6.4 V | -4.8 V to +6.4 V | -4.8 V to +6.4 V |
| Operating Temperature | 0 C to +70 C | 0 C to +70 C | 0 C to +70 C |
| Lifecycle Status | NRN’d (Not Recommended for New Designs) | NRN’d | Active (Microchip) |
أبرز الفروقات
- Inherent 50/60 Hz normal-mode noise rejection (مقابلGeneric 12-bit SAR ADC (e.g. ADS1100A7IDBVRG4))
- True differential inputs with high common-mode range (مقابلSingle-ended 12-bit ADC (e.g. ADC10158CIN/NOPB))
- Self-contained integrating ADC - no external clock IC needed (مقابلSigma-delta ADC requiring MCLK crystal)
ملاحظات التصميم
The MQFP-44 package requires careful layout for the integrating analog section. Place the auto-zero capacitor (C AZ), reference capacitor (C REF), and integrator capacitor (C INT) immediately adjacent to their respective pins with short, symmetrical traces; dielectric absorption in these capacitors directly degrades integral non-linearity. Use C0G / NP0 ceramic or film capacitors rated for low leakage; avoid X7R / X5R for the integrator capacitor when 12-bit accuracy is required. Estimated: with the manufacturer datasheet's recommended capacitor values the integrator output swing stays within the ±4 V linear region, yielding the published ±0.5 LSB INL.
Do not drive the differential analog inputs (INHI / INLO) directly from a low-impedance source exceeding the datasheet's ±4.8 V common-mode range without proper input protection. Tie COMMON to analog ground near the IC, and join the analog and digital grounds only at the ICL7109CMH+D GND pin to avoid ground-loop noise coupling into the integrator. The reference voltage (REF HI / REF LO) must be a low-noise source; tie it to a clean ICL8069 or equivalent rather than to the noisy +5 V rail directly.
The ICL7109CMH+D draws under 30 mW on ±5V supplies per the manufacturer datasheet, but the supply rejection is finite. Use low-ESR decoupling (10 uF tantalum + 0.1 uF ceramic) on each of V+ and V- within 5 mm of the pins. Estimated: ripple above 50 mV on either supply can degrade normal-mode noise rejection by 6-10 dB. For battery-powered or isolated applications, derive V- from a small -5V charge-pump rather than from a noisy switching node.
معلومات الامتثال
RoHS compliant per FindIC verified Web Data; the +D suffix denotes lead-free (Pb-free) terminal plating. REACH compliance not stated in the provided data - listed as 'unknown'. AEC-Q100 not applicable - this is a commercial-grade part in the 0 C to +70 C range; industrial / automotive variants exist in the wider ICL7109 family.
