PIC16C74A-20I/L - 8-Bit 20MHz OTP MCU 7KB | Microchip
MPN: PIC16C74A-20I/L ✓ AktifPIC16C74A-20I/L Genel Bakış
An 8-bit microcontroller (MCU) is a single-chip microcomputer containing a CPU, memory, and peripherals on one die, executing instructions on 8-bit data words. Within the broader taxonomy, the PIC16C74A belongs to the mid-range 8-bit MCU category, itself part of the microcontroller family of embedded processors within the semiconductor hierarchy. OTP memory permits one-time programming during production but cannot be erased afterwards; for erasable variants, Microchip recommends the PIC16F74 Flash-based equivalent.
Key features of the PIC16C74A-20I/L include high sink/source current of 25/25 mA per I/O, low-power consumption (5 µA typical standby at 3V/32 kHz, 15 µA at 5V/4 MHz), a high-performance RISC architecture with only 35 single-word instructions to learn, and all instructions execute in a single cycle except program branches (two cycles). The integrated peripherals include a synchronous serial port (SSP) for SPI/I2C, a USART for asynchronous serial communication, and a parallel slave port for external bus interfaces.
The device is built on a fully-static CMOS process, allowing clock frequencies from DC up to 20 MHz without internal oscillator overhead. The 8-bit A/D converter with 8 input channels enables direct interfacing with analog sensors, while the 192-byte RAM supports small data buffers for real-time control loops. OTP program memory provides cost-effective one-time programming suitable for mature production designs.
Typical applications include industrial control systems, automotive body electronics, appliance controllers, sensor signal conditioning nodes, and embedded data acquisition modules. The 33 I/O pins and integrated ADC make it particularly suitable for multi-channel sensor monitoring applications. When designing with the PIC16C74A-20I/L, verify MCLR reset circuitry and use a 1 µF decoupling capacitor on VDD within 1 cm of the device; the OTP memory cannot be field-updated, so development should use the Flash-based PIC16F74 equivalent before committing to OTP production parts.
This page synthesizes distributor stock and pricing snapshots (as of 2026-09-18), drop-in compatible alternatives in the same 44-PLCC footprint, and practical design notes not found in the original 1997-vintage manufacturer datasheet.
Drop-in alternatifler için PIC16C74A-20I/L — aynı paket, pin-başına uyumlu. PCB yeniden montajı gerektiren farklı paket bileşenleri dışlanmıştır.
Bu Serideki Variantlar
Yedek parça uyumlu olan aynı serideki modeller PIC16C74A-20I/L (aynı form faktörü ve ayağa oturma) — farklı olan Package, Core Architecture, Serial Interfaces, Operating Temperature Range, Mounting Type.
PIC16F74-I/L
✅ YerleştirmeFiyat için iletişime geçin
Veri Şablonunu Görüntüle →PIC16F74T-I/L
✅ YerleştirmeFiyat için iletişime geçin
Veri Şablonunu Görüntüle →PIC16C74B-20I/L
✅ YerleştirmeFiyat için iletişime geçin
Veri Şablonunu Görüntüle →PIC16C74A-20/L
✅ YerleştirmeFiyat için iletişime geçin
Veri Şablonunu Görüntüle →PIC16C74A-20I/L Maksimum Değerlendirmeler & Elektriksel Özellikler
| Core Architecture | 8-bit PIC RISC (mid-range) |
| Instruction Set | 35 single-word instructions |
| Azami Saat Hızı | 20 MHz |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 7 KB (4K x 14) |
| Data RAM | 192 bytes |
| Data EEPROM | Not present on this OTP variant |
| Supply Voltage Range | 2.5 V to 6.0 V |
| I/O Pins | 33 |
| A/D Converter | 8 channels x 8-bit |
| Timer/Counters | 3 (with CCP) |
| Serial Interfaces | SSP (SPI/I2C), USART |
| Parallel Slave Port | Yes (8-bit) |
| I/O Sink/Source Current | 25 mA / 25 mA |
| İşletim Sıcaklığı Aralığı | -40 C to +85 C (Industrial, "I" grade) |
| Paket | 44-pin PLCC (J-Lead) |
| Montaj Türü | Surface Mount (PLCC socket compatible) |
PIC16C74A-20I/L 44-pin plcc (j-lead) Pin Yapısı Kılavuzu
PIC16C74A-20I/L (44-pin plcc (j-lead) paket) için pin yapısı. Bu dijital IC, GPIO, iletişim arayüzleri (UART, SPI, I2C) ve güç pinleri içerir. Alternatif pin işlevleri ve yapılandırma seçenekleri için üretici veri kitapçığını referans alın. Tünel sistem tasarımı ve PCB yerleşimi için temel bir bileşendir.
Ayrıntılı pin çıkış verisi mevcut değil: PIC16C74A-20I/L.
Aşağıdaki veri sayfası tam pin konfigürasyonu için.
Tipik Uygulamalar
PIC16C74A-20I/L için uygundur 6 uygulamas: Industrial Sensor Monitoring, Appliance Control Board, Automotive Body Electronics, Embedded Data Acquisition Module, Security and Access Control, Hobbyist and Educational Embedded Platform.
Industrial Sensor Monitoring
The PIC16C74A-20I/L's 8-channel 8-bit A/D converter and 33 digital I/O pins make it well-suited for multi-channel industrial sensor monitoring. It can directly sample 8 analog inputs (thermistors, pressure transducers, photo-sensors) while driving indicator LEDs, relays, and operator panel switches through its 25 mA sink/source capable ports. Operating from 2.5 V to 6.0 V at industrial temperatures (-40°C to +85°C), the device handles factory-floor environments without additional conditioning. Its 35-instruction RISC core and 20 MHz clock allow tight control loops for process regulation. The 192-byte RAM is adequate for sensor smoothing buffers. OTP memory ensures firmware stability in field-deployed industrial systems that rarely require code updates.
Önerilen
Appliance Control Board
The PIC16C74A-20I/L fits appliance control applications such as washing machines, dishwashers, and HVAC controls where a stable OTP part is preferred for cost reasons. The 33 I/O lines interface directly with mechanical push-buttons, rotary encoders, seven-segment displays, and triac-driven AC loads. Three timer/counters with CCP support precise PWM for motor speed control and proportional valve actuation. The USART enables diagnostics communication with service tools. Operating at 5 V from a simple linear regulator and tolerating up to 6 V, the MCU coexists with noisy relay-driven power stages. OTP memory locks production firmware, preventing field corruption by voltage transients common in white-goods environments.
Önerilen
Automotive Body Electronics
The PIC16C74A-20I/L's industrial temperature rating (-40°C to +85°C) and OTP one-time-programmable memory are useful for automotive body electronics such as mirror controllers, seat position modules, and lighting timers. Its 8-channel ADC reads potentiometers and current-sense amplifiers, while 33 I/O drive MOSFET gates, lamps, and H-bridges. The 20 MHz RISC core executes body-controller state machines efficiently, and the SSP supports SPI peripherals such as CAN-transceiver companion chips. Although Microchip's newer PIC16F family is preferred for AEC-Q100 designs, the PIC16C74A remains in production for cost-sensitive legacy body modules where OTP stability and 25 mA I/O drive eliminate external transistors.
Önerilen
Embedded Data Acquisition Module
The PIC16C74A-20I/L serves as the CPU in standalone data-acquisition front-ends that log multi-channel analog signals to external EEPROM or SD cards. Its 8-bit successive-approximation ADC samples 8 channels with selectable references, while the SSP SPI port streams data to a serial Flash or SD card. The USART provides an RS-232 service-port for data retrieval and configuration. With 192 bytes of RAM, the MCU buffers acquisition frames before storage, and three timer/counters schedule precise sampling intervals. Operating at 5 V from a regulated supply, the device delivers reliable acquisition in instrumentation, environmental monitoring, and laboratory automation where OTP memory locks validated firmware.
Önerilen
Security and Access Control
The PIC16C74A-20I/L is a practical choice for keypad door controllers, RFID readers, and simple alarm panels where 33 I/O lines interface with matrix keypads, magnetic-stripe readers, relay-controlled locks, and sirens. Its 20 MHz RISC core runs the access-control state machine fast enough for real-time PIN validation, while the 192-byte RAM holds the current credential being processed. The SSP/I2C port talks to EEPROM credential storage, and the USART connects to a central monitoring panel. OTP memory prevents firmware tampering — important for security equipment where code-injection attacks must be impossible. Industrial temperature range permits outdoor mounting in secured enclosures.
Önerilen
Hobbyist and Educational Embedded Platform
The PIC16C74A-20I/L is widely used in educational settings and hobbyist electronics projects, particularly with Microchip's MPLAB IDE and PICkit programmers. Its 35-instruction RISC architecture is the canonical teaching example for embedded programming courses, and the 7 KB OTP memory accommodates substantial student projects. The 44-PLCC package fits standard 44-pin PLCC sockets, simplifying breadboarding. With 33 I/O, 8-channel ADC, USART, SPI, I2C, three timers, and CCP PWM, students can implement UART communication, motor control, sensor acquisition, and interrupt-driven design all on one chip. The industrial temperature range allows robust student projects for outdoor demonstrations.
Önerilen
Önerilen Ürünler Özeti
Mühendislik referans verileri: PIC16C74A-20I/L — karşılaştırma, tasarım rehberi ve uyumluluk bilgileri.
Seçim Kılavuzu
Alternatiflerle Karşılaştırma
| Parametre | Bu Ürün | PIC16F74-I/L | PIC16F74T-I/L | PIC16C74B-20I/L | PIC16C74A-20/L | PIC16C74A-20I/PQ |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-PLCC (J-Lead) | 44-PLCC (J-Lead) | 44-PLCC (J-Lead) | 44-PLCC (J-Lead) | 44-PLCC (J-Lead) | 44-MQFP (PQ) — different footprint |
| Program Memory Type | OTP 7 KB | Flash 4 KB | Flash 4 KB | OTP 7 KB | OTP 7 KB | OTP 7 KB |
| Program Memory Size | 7 KB (4K x 14) | 4 KB | 4 KB | 7 KB (4K x 14) | 7 KB (4K x 14) | 7 KB (4K x 14) |
| Maximum Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Voltage | 2.5 V to 6.0 V | 2.0 V to 6.0 V | 2.0 V to 6.0 V | 2.5 V to 6.0 V | 2.5 V to 6.0 V | 2.5 V to 6.0 V |
| Temperature Range | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | 0 C to +70 C (Commercial) | -40 C to +85 C (Industrial) |
| ADC | 8 ch x 8-bit | 8 ch x 8-bit | 8 ch x 8-bit | 8 ch x 8-bit | 8 ch x 8-bit | 8 ch x 8-bit |
| Field Reprogrammable | No (OTP) | Yes (Flash) | Yes (Flash) | No (OTP) | No (OTP) | No (OTP) |
| Approx. Unit Price (USD, as of 2026-09-18) | 13.61 | Lower (Flash, higher volume) | Lower (Flash, tape & reel) | Similar to PIC16C74A | Similar (commercial grade) | Similar (MQFP variant) |
Ana Farklılayıcılar
- Officially endorsed Flash-based successor with field updates (karşılaştırma:PIC16F74-I/L)
- Industrial temperature range and mature OTP stability (karşılaştırma:PIC16C74A-20/L)
- Direct drop-in silicon revision within OTP family (karşılaştırma:PIC16C74B-20I/L)
Tasarım Notları
Place a 0.1 µF ceramic decoupling capacitor within 1 cm of the VDD pin and a 10 µF bulk capacitor near the MCU power pins to suppress switching noise. The PIC16C74A-20I/L has separate AVdd/AVss pins for the ADC; the analog supply must be filtered with a ferrite bead or small inductor and a dedicated 10 µF + 0.1 µF RC network to prevent digital switching noise from coupling into the ADC readings. Brown-out detection at 4.0 V (BOREN enabled) is recommended for unreliable supply rails to avoid corruption of the OTP program memory.
OTP program memory can be programmed only once; any bug in firmware becomes permanent. Always develop and validate on a PIC16F74-I/L (Flash, same footprint) before committing to PIC16C74A-20I/L for production. Watch the MCLR pin: floating or weak pull-up can cause intermittent resets — use a 10 kΩ pull-up to Vdd and a 100 nF capacitor to ground for stable operation. The 8-bit ADC's reference voltage pins (Vref+/Vref-) must be sourced from low-impedance drivers (≤10 Ω) — using Vdd as reference without buffering introduces 1-2 LSB of ADC error.
The 44-PLCC package should be socketed (e.g., 44-pin PLCC thru-hole or SMT socket) for prototype development, allowing easy swap between PIC16C74A-20I/L (OTP) and PIC16F74-I/L (Flash) during firmware validation. Place the ICSP programming header (Vpp, Vdd, GND, RB6/PGC, RB7/PGD) on a 0.1-inch pitch 5-pin header on the board edge for factory programming access. Keep the 20 MHz crystal traces short and symmetric, with load capacitors (typically 15-33 pF) returned to GND within 5 mm of the OSC1/OSC2 pins to avoid parasitic oscillation modes.
Uyumluluk Bilgisi
RoHS and lead-free status confirmed via Microchip product page and distributor listings. The ICE product is not AEC-Q100 qualified; Microchip's newer PIC16F family typically carries automotive grade for body-electronics applications. Conflict-minerals compliance per Microchip corporate policy.
