ICL7109CMH+T - 12-Bit Dual-Slope ADC, 44-MQFP | Maxim Integrated
MPN: ICL7109CMH+T ✓ AktifICL7109CMH+T Ringkasan
What is a dual-slope integrating ADC? It is a type of analog-to-digital converter that uses a two-stage integration process: first it integrates the input voltage over a fixed time, then it integrates a reference voltage of opposite polarity until the integrator output returns to zero. The number of clock cycles required for the second integration is proportional to the input voltage. Dual-slope ADCs sit within the broader ADC taxonomy, which includes successive-approximation-register (SAR), sigma-delta, and flash converters. They are valued for excellent normal-mode noise rejection at integer multiples of the integration period, making them ideal for noisy industrial environments.
The ICL7109 family employs CMOS technology to achieve low power consumption while delivering true 12-bit performance with ±1 LSB total uncalibrated accuracy. The device integrates BCD/three-state binary output drivers, a precision bandgap reference, and a charge-balance converter. Differential input capability and high common-mode rejection enable direct connection to bridge sensors and thermocouples without front-end instrumentation amplifiers. Active-low RUN/HOLD and BUSY handshake lines allow direct connection to UARTs and parallel microprocessor busses.
Typical applications include digital panel meters, weigh scales, process control loops, thermometry with thermocouple/PT100 front ends, pH meters, blood analyzers, and battery-powered portable instrumentation. The wide supply range (typically ±5 V or single +5 V) and commercial temperature grade (0°C to +70°C) suit industrial and bench instruments. For systems requiring noise-immune A/D conversion with deterministic integration behavior, the ICL7109 remains a proven workhorse, and the ICL7109CMH+T variant comes in surface-mount 44-MQFP for automated assembly.
When designing with the ICL7109CMH+T, place the integrating and reference capacitors with low-leakage, low-dielectric-absorption types (typically polypropylene or polystyrene) directly at the chip pins. Use a guard ring around the integrator input to minimize leakage current from the PCB. The crystal oscillator reference capacitor and integrating RC networks should be sized for the chosen conversion rate: a 3.58 MHz crystal yields roughly 30 conversions/second. Do not exceed the absolute maximum analog input voltage of ±15 V relative to supply ground.
Alternatif penggantian untuk ICL7109CMH+T — paket yang sama, pin-pada-pin kompatibel. Bagian paket yang berbeda memerlukan kerja ulang PCB diabaikan.
Variasi di dalam seri ini
Model-series yang sama yang kompatibel dengan penggantian ICL7109CMH+T (sama faktor bentuk dan footprint) — berbeda di dalam Mounting Type, Resolution.
ICL7109CMH+
✅ Drop-InKontak untuk harga
Lihat Datasheet →TC7109ACKW
✅ Drop-In📋 Alternatif referensi (tidak dalam katalog)
ICL7109CMH+T Rating Maksimal & Karakteristik Listrik
| Resolusi | 12 bits + sign + over-range |
| Architecture | Dual-slope integrating |
| Number of Channels | 1 differential input |
| Tipe Output | Three-state binary (with polarity and over-range) |
| Paket | 44-MQFP (10x10 mm, Metric Quad Flat Pack) |
| Jumlah Pin | 44 |
| Terminal Form | GULL WING |
| Package Code | QFP |
| Package Shape | SQUARE |
| Temperature Grade | COMMERCIAL |
| Maximum Conversion Rate | 30 conversions/sec at 3.58 MHz crystal |
| Uncalibrated Accuracy | ±1 LSB (max) |
| Reference | Internal bandgap (external reference option) |
| Tipe Mounting | Surface Mount |
Konfigurasi Pin ICL7109CMH+T
| Pin produk 1 | GND — Digital ground |
| Pin produk 2 | STATUS — Status output |
| Pin produk 3 | POL — Polarity output |
| Pin produk 4 | OR — Over-range output |
| Pin produk 5 | B12 — Bit 12 (MSB) three-state output |
| Pin produk 6 | B11 — Bit 11 three-state output |
| Pin produk 7 | B10 — Bit 10 three-state output |
| Pin produk 8 | B9 — Bit 9 three-state output |
| Pin produk 9 | B8 — Bit 8 three-state output |
| Pin produk 10 | B7 — Bit 7 three-state output |
| Pin produk 11 | B6 — Bit 6 three-state output |
| Pin produk 12 | B5 — Bit 5 three-state output |
| Pin produk 13 | B4 — Bit 4 three-state output |
| Pin produk 14 | B3 — Bit 3 three-state output |
| Pin produk 15 | B2 — Bit 2 three-state output |
| Pin produk 16 | B1 — Bit 1 (LSB) three-state output |
| Pin produk 17 | TEST — Test pin |
| Pin produk 18 | OSC1 — Oscillator input |
| Pin produk 19 | OSC3 — Oscillator output |
| Pin produk 20 | OSC2 — Oscillator |
| Pin produk 21 | REF HI — Reference voltage high |
| Pin produk 22 | REF LO — Reference voltage low |
| Pin produk 23 | REF CAP+ — Reference capacitor positive |
| Pin produk 24 | REF CAP- — Reference capacitor negative |
| Pin produk 25 | INT IN — Integrator input |
| Pin produk 26 | INT OUT — Integrator output |
| Pin produk 27 | BUFFER OUT — Buffer output |
| Pin produk 28 | C REF+ — Auto-zero capacitor positive |
| Pin produk 29 | C REF- — Auto-zero capacitor negative |
| Pin produk 30 | IN HI — Analog input high |
| Pin produk 31 | IN LO — Analog input low |
| Pin produk 32 | COMMON — Common (analog ground) |
| Pin produk 33 | V- — Negative supply |
| Pin produk 34 | RUN/HOLD — Run/Hold control input |
| Pin produk 35 | MODE — Mode select input |
| Pin produk 36 | SEND — Send input |
| Pin produk 37 | CE — Chip enable |
| Pin produk 38 | LBEN — Low-byte enable |
| Pin produk 39 | HBEN — High-byte enable |
| Pin produk 40 | V+ — Positive supply |
| Pin produk 41 | DGND — Digital ground |
| Pin produk 42 | NC — Not connected (per datasheet) |
| Pin produk 43 | NC — Not connected (per datasheet) |
| Pin produk 44 | NC — Not connected (per datasheet) |
Aplikasi Umum
ICL7109CMH+T cocok untuk 6 aplikasis: Digital Panel Meter (DPM), Weigh Scale / Load Cell Instrumentation, Process Control Loop Monitoring, Thermometry with Thermocouple Front End, pH / Blood Analyzer Bench Instruments, Battery-Powered Portable Instrumentation.
Digital Panel Meter (DPM)
The ICL7109CMH+T's 12-bit resolution and dual-slope architecture make it ideal for digital panel meters reading ±2V full scale. Its 60Hz normal-mode noise rejection at 3.58MHz crystal cuts through industrial mains noise, while the differential input accepts low-level sensor signals directly. Use the three-state binary outputs plus sign/over-range flags for processor display multiplexing or direct LCD driver interfacing.
Direkomendasikan
Weigh Scale / Load Cell Instrumentation
Weigh scales rely on the ICL7109CMH+T's 12-bit resolution, differential input, and excellent line-frequency noise rejection to read strain-gauge bridge outputs accurately. With 3.58MHz crystal the integrator naturally rejects 60Hz pickup common in industrial environments, achieving better than 0.1% accuracy without calibration. Pair the ICL7109CMH+T with an instrumentation amp front end and force-sensor bridge for direct kilogram/pound readout.
Direkomendasikan
Process Control Loop Monitoring
Process control loops use the ICL7109CMH+T to digitize 4-20mA or 0-10V sensor signals with high noise immunity. The dual-slope integrator rejects switching-converter noise from nearby motor drives and solenoid valves. Three-state binary outputs interface directly to industrial PLC backplanes or UARTs, while the BUSY handshake line simplifies interrupt-driven sample acquisition in SCADA systems.
Direkomendasikan
Thermometry with Thermocouple Front End
The ICL7109CMH+T handles thermocouple millivolt signals through its differential input with high common-mode rejection. Combined with cold-junction compensation and an instrumentation amp, the ADC delivers 12-bit temperature readings suitable for industrial furnace and oven monitoring. Dual-slope integration filters thermocouple lead-wire 50/60Hz pickup, improving stability in long-cable installations.
Direkomendasikan
pH / Blood Analyzer Bench Instruments
Clinical chemistry analyzers benefit from the ICL7109CMH+T's high-resolution differential measurement of pH electrode and ion-selective probe outputs. The integrating architecture's normal-mode noise rejection delivers stable readings in electrically noisy laboratory environments. Its commercial temperature grade suits bench-top analyzers, while low power consumption keeps thermal load on precision analog front ends to a minimum.
Direkomendasikan
Battery-Powered Portable Instrumentation
Although the ICL7109CMH+T is not the lowest-power ADC, it remains popular in portable digital multimeters and field instruments where noise rejection and 12-bit accuracy outweigh conversion speed. CMOS technology keeps quiescent current modest for the conversion period, and the on-chip reference eliminates external regulator bulk. Surface-mount 44-MQFP packaging supports compact handheld enclosures used by field technicians.
Direkomendasikan
Ringkasan Produk Direkomendasikan
Data referensi engineering untuk ICL7109CMH+T — pembandingan, panduan desain, dan informasi konformitas.
Panduan Pemilihan
Pembandingan dengan Alternatif
| Parameter Umum | Produk Ini | ICL7109CMH+ | TC7109IJL | TC7109ACKW |
|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Microchip Technology | Microchip Technology |
| Package | 44-MQFP (10x10) | 44-MQFP (10x10) - same | 44-PLCC - different | 44-MQFP (10x10) - same |
| Resolution | 12-bit + sign + OR | 12-bit + sign + OR | 12-bit + sign + OR | 12-bit + sign + OR |
| Architecture | Dual-slope integrating | Dual-slope integrating | Dual-slope integrating | Dual-slope integrating |
| Conversion Rate | 30 conv/sec @ 3.58 MHz | 30 conv/sec @ 3.58 MHz | 30 conv/sec @ 3.58 MHz | 30 conv/sec @ 3.58 MHz |
| Uncalibrated Accuracy | ±1 LSB | ±1 LSB | ±1 LSB | ±1 LSB |
| VOH Source Current | Standard | Standard | Standard | Improved (TC7109A enhancement) |
| Pin-to-Pin on 44-MQFP Footprint | Yes (reference) | Yes | No (44-PLCC differs) | Yes |
Diferensiator Kunci
- Tape-and-reel packaging for SMT production (vsICL7109CMH+)
- Proven noise-rejection architecture for industrial environments (vsTC7109ACKW)
- Direct microprocessor/UART interface (vsICL7107CM44)
Catatan Desain
Use a PCB guard ring tied to COMMON (pin 32) around the integrator input node (pin 25) and its capacitor/resistor to minimize leakage current from PCB contamination. Surface-mount boards with no-clean flux residue can introduce nanoampere-level leakage currents that degrade linearity at 12-bit resolution. Place the integrator capacitor (typically 0.22µF polypropylene) directly at pins 25-26 with the shortest possible trace length. Estimated: at room temperature with 10nA leakage, a 0.22µF integrator integrates approximately 4.5 LSBs of error per conversion over a 100ms integration window.
Bypass V+ (pin 40) and V- (pin 33) supplies with 10µF tantalum in parallel with 0.1µF ceramic capacitors placed within 5mm of the supply pins. The ICL7109CMH+T's charge-pump action during integrator reset can inject switching noise into the supply rails; insufficient decoupling causes 1-2 LSB noise coupling into the reference. Use separate analog and digital ground returns joined only at the ADC's GND/COMMON pins to prevent digital output driver currents from corrupting the analog integrator node.
Do not substitute generic ceramic (X7R/Y5V) capacitors for the integrator (INT, pin 25-26) and reference (REF CAP, pin 23-24) capacitors. These capacitor types exhibit high dielectric absorption (>2%) which directly degrades dual-slope linearity and causes conversion-to-conversion drift. Use polypropylene, polystyrene, or NPO/C0G ceramic types for these positions. Auto-zero capacitor (C REF, pins 28-29) can use a higher-grade ceramic but should still avoid high-DA types like Z5U. Per the Maxim datasheet, integrator capacitor tolerance should be ±5% or better.
Informasi Konformitas
RoHS/REACH compliance status was not provided in the verified web data and should be confirmed via the manufacturer's latest declaration. The 'T' suffix denotes tape-and-reel packaging and the part is supplied lead-free per modern Maxim/Analog Devices manufacturing practice, but exact RoHS compliance should be verified through the manufacturer product folder before production use.
