PIC16C74AT-20I/PT - 8-Bit 20MHz OTP MCU 7KB | Microchip
MPN: PIC16C74AT-20I/PT ✗ انتهى عمره الإنتاجيPIC16C74AT-20I/PT نظرة عامة
An 8-bit microcontroller (MCU) is a single-chip computer built around an 8-bit data path, typically integrating a CPU core, program memory (ROM/OTP/Flash), working RAM, and a mix of peripherals (timers, ADC, communication ports, GPIO). PIC microcontrollers from Microchip Technology are RISC-based Harvard-architecture devices with a small instruction set (35 single-word instructions on the mid-range family) that simplifies coding while still offering deterministic real-time performance. PIC16C parts sit in the mid-range PIC taxonomy: PIC10/12/16/18 (8-bit) -> PIC16F/PIC16C mid-range family -> PIC16C7X sub-family (with integrated ADC). This hierarchy matters because selecting within the same family guarantees pinout, peripheral set, and instruction-set compatibility.
Key differentiating features include the integrated 8-bit ADC, hardware USART for RS-232/RS-485 links, dual CCP modules for PWM or input-capture timing, and a synchronous serial port that can be configured for SPI or I2C master mode. The OTP memory allows short programming lead time for prototype builds but is single-write only, so engineers should plan migration to a Flash-based PIC16F or PIC18 equivalent for production volumes.
At the architectural level the PIC16C74A uses a 14-bit instruction word and separate program/data buses, allowing the CPU to fetch an instruction while simultaneously reading data memory - the canonical Harvard advantage. Power management is handled by selectable oscillator modes (XT, HS, RC, LP) and a power-saving SLEEP state with multiple wake-up sources including the Watchdog Timer.
Typical applications include industrial control boards, appliance controllers, automotive body electronics (pre-CAN modules), sensor signal conditioning with on-chip ADC, and small motor-control loops leveraging the CCP/PWM peripherals. The wide industrial temperature range makes the -I grade suitable for factory-floor equipment.
When designing with this part, plan OTP programming workflow early - the device cannot be re-programmed and the same silicon is unavailable in Flash. The TQFP-44 footprint is shared with PIC16F874/877 Flash equivalents that are drop-in code-and-pin compatible, easing migration paths.
This page synthesizes distributor pricing snapshots, drop-in compatible Microchip alternatives (PIC16C74AT-20I/PQ, PIC16C74AT-20/PT, PIC16C74A-20I/L), and practical design considerations not found in the manufacturer datasheet.
بدائل مباشرة لـ PIC16C74AT-20I/PT — 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 PIC16C74AT-20I/PT (نفس عامل الشكل والبصمة) — يختلف في ADC, Core Architecture, Operating Temperature Range, Package, Program Memory Type.
PIC16C74AT-20/PT
✅ بديل مباشر ⚠️ مواصفات غير مُتحقق منهاتواصل لمعرفة السعر
عرض ورقة البيانات ←PIC16C74AT-10I/PT
✅ بديل مباشر ⚠️ مواصفات غير مُتحقق منهاتواصل لمعرفة السعر
عرض ورقة البيانات ←PIC16C74A-20I/L
✅ بديل مباشر ⚠️ مواصفات غير مُتحقق منهاتواصل لمعرفة السعر
عرض ورقة البيانات ←PIC16F874A-I/PT
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
PIC16F877A-I/PT
✅ بديل مباشرتواصل لمعرفة السعر
عرض ورقة البيانات ←PIC16F874-20I/PT
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
PIC16C74AT-20I/PT الحدود القصوى والخصائص الكهربائية
| Core | 8-bit PIC16C mid-range RISC |
| Instruction Word Width | 14-bit |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 7 KB (4K x 14) |
| Data RAM | 192 bytes |
| Data EEPROM | 0 bytes (not present on this family) |
| Maximum CPU Frequency | 20 MHz |
| Performance | 5 MIPS |
| Instruction Set Size | 35 single-word instructions |
| نطاق درجة حرارة التشغيل | -40 C to +85 C (Industrial -I grade) |
| العلبة | 44-pin TQFP (PT), 10x10 mm body |
| نوع التركيب | Surface Mount |
| I/O Pins | 33 |
| ADC | 8-channel, 8-bit integrated |
| Timers | 3 (Timer0, Timer1, Timer2) |
| CCP Modules | 2 (Capture/Compare/PWM) |
| Serial Interfaces | USART (SCI), SSP (SPI / I2C master) |
تكوين أطراف PIC16C74AT-20I/PT
| دبوس 1 | MCLR/VPP — Master Clear (Reset) input / Programming voltage |
| دبوس 2 | RA0/AN0 — PORTA bit 0 / Analog input channel 0 |
| دبوس 3 | RA1/AN1 — PORTA bit 1 / Analog input channel 1 |
| دبوس 4 | RA2/AN2 — PORTA bit 2 / Analog input channel 2 |
| دبوس 5 | RA3/AN3/VREF — PORTA bit 3 / Analog input 3 / ADC reference |
| دبوس 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| دبوس 7 | RA5/AN4/SS — PORTA bit 5 / Analog input 4 / SPI slave select |
| دبوس 8 | VSS — Ground reference |
| دبوس 9 | OSC1/CLKIN — Oscillator crystal input / external clock |
| دبوس 10 | OSC2/CLKOUT — Oscillator crystal output / clock out |
| دبوس 11 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / T1 clock |
| دبوس 12 | RC1/T1OSI/CCP2 — PORTC bit 1 / T1 oscillator in / CCP2 output |
| دبوس 13 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM output |
| دبوس 14 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| دبوس 15 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| دبوس 16 | RC5/SDO — PORTC bit 5 / SPI data out |
| دبوس 17 | RC6/TX/CK — PORTC bit 6 / USART TX / clock |
| دبوس 18 | RC7/RX/DT — PORTC bit 7 / USART RX / data |
| دبوس 19 | VSS — Ground |
| دبوس 20 | VDD — Positive supply |
| دبوس 21 | RB0/INT — PORTB bit 0 / External interrupt |
| دبوس 22 | RB1 — PORTB bit 1 |
| دبوس 23 | RB2 — PORTB bit 2 |
| دبوس 24 | RB3/PGM — PORTB bit 3 / Low-voltage programming |
| دبوس 25 | RB4 — PORTB bit 4 |
| دبوس 26 | RB5 — PORTB bit 5 |
| دبوس 27 | RB6/PGC — PORTB bit 6 / ICSP clock |
| دبوس 28 | RB7/PGD — PORTB bit 7 / ICSP data |
| دبوس 29 | VSS — Ground |
| دبوس 30 | VDD — Positive supply |
| دبوس 31 | RD0/PSP0 — PORTD bit 0 / Parallel slave port |
| دبوس 32 | RD1/PSP1 — PORTD bit 1 / PSP |
| دبوس 33 | RD2/PSP2 — PORTD bit 2 / PSP |
| دبوس 34 | RD3/PSP3 — PORTD bit 3 / PSP |
| دبوس 35 | RD4/PSP4 — PORTD bit 4 / PSP |
| دبوس 36 | RD5/PSP5 — PORTD bit 5 / PSP |
| دبوس 37 | RD6/PSP6 — PORTD bit 6 / PSP |
| دبوس 38 | RD7/PSP7 — PORTD bit 7 / PSP |
| دبوس 39 | VSS — Ground |
| دبوس 40 | VDD — Positive supply |
| دبوس 41 | RE0/RD/AN5 — PORTE bit 0 / Read strobe / Analog 5 |
| دبوس 42 | RE1/WR/AN6 — PORTE bit 1 / Write strobe / Analog 6 |
| دبوس 43 | RE2/CS/AN7 — PORTE bit 2 / Chip select / Analog 7 |
| دبوس 44 | NC — Not connected (per datasheet) |
التطبيقات النموذجية
PIC16C74AT-20I/PT مناسب لـ 6 التطبيقs: Industrial Control Boards, Appliance Controllers (Washers, Ovens, HVAC), Automotive Body Electronics (Pre-CAN Era), Sensor Signal Conditioning and Data Logging, Small Motor Control (Brushed DC, Stepper), Hobbyist and Educational Projects.
Industrial Control Boards
The PIC16C74AT-20I/PT suits industrial control boards because its industrial -40C to +85C operating temperature range covers factory-floor ambient swings, the 5 MIPS throughput handles PID loops and discrete I/O scanning, and the integrated 8-channel 8-bit ADC reads process sensors (pressure, temperature, flow) without external ADCs. Placed as the main MCU on a control PCB, it scans up to 8 analog inputs at up to 20 MHz while driving relays or triacs via the CCP/PWM outputs. Compared to a switching-supply-based system, the PIC16C74A's deterministic 4-clock-per-instruction cycle gives jitter-free PWM at the on-chip CCP modules - important when synchronizing motor drives or thyristor firing pulses.
موصى به
Appliance Controllers (Washers, Ovens, HVAC)
The PIC16C74AT-20I/PT fits appliance controllers because the 8-bit ADC reads thermistor/pressure-sensor inputs directly, the USART handles user-interface displays or expansion modules, and the two CCP/PWM channels drive motor-control or triac-trigger circuits. The industrial temperature grade allows installation near heat-generating components like motors and heaters without derating. Compared to a discrete 8051 solution, the PIC16C74A's integrated ADC eliminates external glue logic, while the 33 I/O lines multiplex keypad, LCD, and relay outputs - saving PCB area in cost-sensitive consumer appliance designs.
موصى به
Automotive Body Electronics (Pre-CAN Era)
The PIC16C74AT-20I/PT works in pre-CAN automotive body modules such as seat controllers, mirror adjusters, and lighting drivers because the industrial -40C to +85C temperature range handles under-dash environments, the ADC monitors position feedback, and the CCP/PWM outputs drive small DC motors or LED strings. The USART supports LIN-like single-wire communication with other body modules. Compared to automotive-grade PIC18 alternatives, the PIC16C74AT-20I/PT is NOT AEC-Q100 qualified - for modern automotive designs choose PIC18F-K42 or dsPIC33 families. The OTP memory also makes it unsuitable for late-stage firmware updates required in current production vehicles.
موصى به
Sensor Signal Conditioning and Data Logging
The PIC16C74AT-20I/PT conditions and logs sensor signals because its 8-channel 8-bit ADC reads multiple transducers (thermistors, photocells, strain gauges), the 192-byte RAM buffers samples, and the USART streams data to a host PC or external EEPROM. The 5 MIPS throughput allows 8-bit ADC sampling rates up to the converter's full bandwidth while leaving cycles for serial output. Compared to a discrete op-amp + ADC + microcontroller chain, integrating the ADC on-chip reduces BOM cost and analog noise pickup. Engineers should add external analog filtering on each ADC input - the on-chip ADC has no input buffer.
موصى به
Small Motor Control (Brushed DC, Stepper)
The PIC16C74AT-20I/PT drives small brushed-DC or bipolar stepper motors because its two CCP/PWM modules generate up to two independent PWM channels at 20 MHz, the 5 MIPS throughput runs the acceleration/deceleration profile, and the ADC reads current-sense resistors for closed-loop torque control. Operating at industrial temperatures allows use in motor-housing environments. Compared to a dedicated motor-driver ASIC, the PIC16C74A's programmable firmware adapts to different motor characteristics via software - no ASIC mask change. The 192-byte RAM is the main limitation for storing long motion profiles.
موصى به
Hobbyist and Educational Projects
The PIC16C74AT-20I/PT is popular in educational settings because the PIC16 mid-range architecture is well-documented in textbooks and the part's 33 I/O pins support student projects ranging from LED matrices to simple robotics. The 5 MIPS throughput handles real-time tasks like line-following robots or music synthesizers, while the integrated ADC enables sensor-based experiments. Compared to modern PIC16F1xx or Arduino-class MCUs, the OTP memory is a teaching negative - students cannot iterate firmware quickly. For classroom use, the PIC16F874A-I/PT (same TQFP-44 footprint, Flash memory) is the modern educational equivalent.
موصى به
ملخص المنتجات الموصى بها
بيانات مرجعية هندسية لـ PIC16C74AT-20I/PT — المقارنة وإرشادات التصميم ومعلومات الامتثال.
دليل الاختيار
المقارنة مع البدائل
| المعامل | هذا المنتج | PIC16F874A-I/PT | PIC16F877A-I/PT | PIC16F874-20I/PT | PIC16C74AT-20/PT | PIC16C74AT-10I/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin TQFP (PT) 10x10 mm | 44-pin TQFP (PT) 10x10 mm - same | 44-pin TQFP (PT) 10x10 mm - same | 44-pin TQFP (PT) 10x10 mm - same | 44-pin TQFP (PT) 10x10 mm - same | 44-pin TQFP (PT) 10x10 mm - same |
| Core Architecture | PIC16 mid-range 8-bit RISC | PIC16 mid-range 8-bit RISC (same) | PIC16 mid-range 8-bit RISC (same) | PIC16 mid-range 8-bit RISC (same) | PIC16 mid-range 8-bit RISC (same) | PIC16 mid-range 8-bit RISC (same) |
| Program Memory | 7 KB OTP | 7 KB Flash (reprogrammable) | 14 KB Flash | 7 KB Flash | 7 KB OTP | 7 KB OTP |
| RAM | 192 bytes | 192 bytes | 368 bytes | 192 bytes | 192 bytes | 192 bytes |
| Maximum Clock | 20 MHz (5 MIPS) | 20 MHz (5 MIPS) | 20 MHz (5 MIPS) | 20 MHz (5 MIPS) | 20 MHz (5 MIPS) | 10 MHz (2.5 MIPS) -50% |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) |
| ADC | 8-channel, 8-bit | 8-channel, 8-bit (same) | 8-channel, 10-bit | 8-channel, 8-bit (same) | 8-channel, 8-bit (same) | 8-channel, 8-bit (same) |
| Lifecycle Status | Obsolete | Active (in production) | Active (in production) | Active (in production) | Obsolete | Obsolete |
أبرز الفروقات
- OTP memory fits existing PIC16C firmware base (مقابلPIC16F874A-I/PT)
- Industrial -I temperature grade standard (مقابلPIC16C74AT-20/PT)
- Mid-range family compatibility preserves investment (مقابلPIC18F4550-I/PT)
- Dual CCP/PWM modules for two-axis motor control (مقابلPIC16F874-20I/PT)
ملاحظات التصميم
The PIC16C74AT-20I/PT uses OTP (One-Time Programmable) EPROM that cannot be erased or rewritten - any firmware bug after the first programming is permanent. For prototypes and development cycles, fit the PCB with the Flash-based PIC16F874A-I/PT (same 44-pin TQFP footprint, identical peripheral register map and instruction set) so firmware can be revised via ICSP. Migrate to the OTP part only after firmware is fully validated and production units are ready to be programmed once. The 'A' silicon revision PIC16C74A is electrically identical to PIC16C74 but adds a documented errata fix in the ADC module.
Estimated: the PIC16C74AT-20I/PT core draws approximately 5-10 mA at 20 MHz with Vdd = 5V. Add bulk decoupling of 10 uF electrolytic + 100 nF ceramic near each Vdd/Vss pair (the TQFP-44 package has four Vdd/Vss pin pairs: pins 8/7, 20/19, 30/29, 40/39). Place the 100 nF capacitors within 5 mm of the Vdd pins to suppress switching transients during CCP/PWM edges. For battery-powered applications use the LP oscillator mode (32 kHz watch crystal) and SLEEP state to drop current below 1 uA; the Wake-on-interrupt or Watchdog Timer features then provide automatic restart.
The 44-pin TQFP (PT) package has a 0.8 mm pitch and 10x10 mm body - design PCB land pads per IPC-7351 nominal-density footprint (approximately 0.30 mm pad width, 1.55 mm pad length). The package has an exposed thermal pad (die-down flag) at the center that should be soldered to a 6x6 mm copper pour connected to Vss for thermal dissipation; without this pad soldered, junction-to-ambient thermal resistance rises and the part can overheat at 20 MHz full-load. Pin 1 indicator is a dimple on the top side of the package. Add a 4-6 mm keep-out under the IC body to allow rework.
The PIC16C74AT-20I/PT has no Schmitt trigger on PORTA analog-capable pins (RA0-RA5) when configured as digital inputs; if these pins are exposed to slow edges (RC-filtered sensors, long PCB traces), add an external Schmitt trigger or hysteresis comparator to prevent oscillation. The ADC inputs share pins with PORTA digital I/O - configure them as analog inputs (ANSEL register on the 'A' silicon) before reading to avoid digital noise coupling. Place a 100 nF ceramic + 10 uF bulk capacitor near the AVdd pin (if available on this family, otherwise share Vdd) to keep ADC reference stable during conversion.
معلومات الامتثال
PIC16C74AT-20I/PT predates widespread RoHS adoption. The 'T' suffix in the part number indicates tape-and-reel packaging. Not AEC-Q100 qualified - for automotive use choose PIC18F-K42 or dsPIC33 families.
