PIC16C74B-20I/L - 8-Bit 20MHz OTP MCU 7KB | 44-PLCC | Microchip
MPN: PIC16C74B-20I/L ✓ Hoạt độngPIC16C74B-20I/L Tóm tắt
An 8-bit microcontroller (MCU) is a small, self-contained computer-on-a-chip built around an 8-bit data path, on-chip program memory, RAM, and a set of peripherals. PIC16C MCUs are part of the broader category of RISC microcontrollers within the semiconductor power-management and embedded-control taxonomy: MCU -> microcontroller -> embedded processor -> semiconductor. They target deterministic, low-cost, low-power embedded control where a full 32-bit processor would be overkill.
Key features of the PIC16C74B include 8 channels of 8-bit Analog-to-Digital conversion, two additional timers, two Capture/Compare/PWM peripherals, and a synchronous serial port configurable as either 3-wire SPI or 2-wire I2C, plus a USART for asynchronous serial communication. The high-performance RISC CPU uses only 35 single-word instructions, with all instructions executing in one cycle except program branches (two cycles), enabling predictable real-time response.
The OTP program memory, parallel I/O architecture, and ceramic PLCC windowed package indicate this part is intended for prototype development, low-volume industrial production, and legacy industrial control systems where field-programmability is not required. Compared with flash-based successors like PIC16F74, this OTP variant offers lower unit cost in volume but cannot be re-programmed.
Typical applications include industrial control systems, motor control, sensor interfacing, building automation, embedded instrumentation, and legacy retrofit designs. The wide industrial temperature range and robust peripheral set make the PIC16C74B well suited for factory-floor equipment.
When designing with the PIC16C74B, ensure your programmer supports OTP devices - a windowed CERDIP/PLCC package allows UV erasure for development iteration, but production programming must be done before final encapsulation. Decoupling capacitors (100 nF plus 10 uF bulk) should be placed within 5 mm of VDD pins.
This page synthesizes verified distributor pricing, drop-in pin-compatible alternatives, and practical engineering notes not consolidated on any single distributor or manufacturer page, helping engineers make sourcing and substitution decisions in seconds.
Bộ thay thế dễ dàng lắp đặt cho PIC16C74B-20I/L — 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 PIC16C74B-20I/L (cùng hình factor và footprint) — khác nhau ở Core Architecture, Timers, Package, Serial Interfaces, Program Memory Size.
PIC16C74B-20/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74B-04I/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74B-04E/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74A-20I/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C67-20I/PQ
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74B-20I/L Tỷ lệ tối đa & tính chất điện
| Core Architecture | 8-bit PIC RISC |
| Program Memory Size | 7 KB (4K x 14) |
| Program Memory Type | OTP (One-Time Programmable) |
| RAM Size | 192 bytes |
| Tần số xung maksimum | 20 MHz |
| Instruction Cycle | 200 ns |
| Supply Voltage Range | 4.0 V to 5.5 V |
| Number of I/O Pins | 33 |
| ADC | 8 channels, 8-bit |
| Timers | 3 (Timer0, Timer1, Timer2) |
| Capture/Compare/PWM | 2 modules |
| Communication Interfaces | SPI, I2C (MSSP), USART |
| Khoảng nhiệt độ hoạt động | -40 C to +85 C (Industrial) |
| Package Type | 44-pin PLCC (J-Lead), windowed ceramic |
| Package Dimensions | 16.59 x 16.59 mm |
| Kiểu lắp đặt | Surface Mount |
Cấu hình chân PIC16C74B-20I/L
| Chân 1 | MCLR — Master Clear (Reset) input |
| Chân 2 | RA0/AN0 — Port A bit 0 / Analog input 0 |
| Chân 3 | RA1/AN1 — Port A bit 1 / Analog input 1 |
| Chân 4 | RA2/AN2 — Port A bit 2 / Analog input 2 |
| Chân 5 | RA3/AN3/VREF — Port A bit 3 / Analog input 3 / Voltage Reference |
| Chân 6 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Chân 7 | RA5/AN4/SS — Port A bit 5 / Analog input 4 / SPI Slave Select |
| Chân 8 | RE0/RD — Port E bit 0 / Read control for parallel slave port |
| Chân 9 | RE1/WR — Port E bit 1 / Write control for parallel slave port |
| Chân 10 | RE2/CS — Port E bit 2 / Chip Select for parallel slave port |
| Chân 11 | VDD — Positive supply voltage |
| Chân 12 | VSS — Ground |
| Chân 13 | OSC1/CLKIN — Oscillator input / external clock input |
| Chân 14 | OSC2/CLKOUT — Oscillator output / clock output |
| Chân 15 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer1 oscillator output / Timer1 clock input |
| Chân 16 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator input / CCP2 |
| Chân 17 | RC2/CCP1 — Port C bit 2 / Capture/Compare/PWM1 |
| Chân 18 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Chân 19 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Chân 20 | RC5/SDO — Port C bit 5 / SPI data out |
| Chân 21 | RC6/TX/CK — Port C bit 6 / USART transmit / USART clock |
| Chân 22 | RC7/RX/DT — Port C bit 7 / USART receive / USART data |
| Chân 23 | RD0/PSP0 — Port D bit 0 / Parallel Slave Port bit 0 |
| Chân 24 | RD1/PSP1 — Port D bit 1 / Parallel Slave Port bit 1 |
| Chân 25 | RD2/PSP2 — Port D bit 2 / Parallel Slave Port bit 2 |
| Chân 26 | RD3/PSP3 — Port D bit 3 / Parallel Slave Port bit 3 |
| Chân 27 | RD4/PSP4 — Port D bit 4 / Parallel Slave Port bit 4 |
| Chân 28 | RD5/PSP5 — Port D bit 5 / Parallel Slave Port bit 5 |
| Chân 29 | RD6/PSP6 — Port D bit 6 / Parallel Slave Port bit 6 |
| Chân 30 | RD7/PSP7 — Port D bit 7 / Parallel Slave Port bit 7 |
| Chân 31 | RB0/INT — Port B bit 0 / External interrupt |
| Chân 32 | RB1 — Port B bit 1 |
| Chân 33 | RB2 — Port B bit 2 |
| Chân 34 | RB3 — Port B bit 3 |
| Chân 35 | RB4 — Port B bit 4 |
| Chân 36 | RB5 — Port B bit 5 |
| Chân 37 | RB6/PGC — Port B bit 6 / ICSP clock |
| Chân 38 | RB7/PGD — Port B bit 7 / ICSP data |
| Chân 39 | NC — Not connected (per datasheet) |
| Chân 40 | NC — Not connected (per datasheet) |
| Chân 41 | NC — Not connected (per datasheet) |
| Chân 42 | NC — Not connected (per datasheet) |
| Chân 43 | NC — Not connected (per datasheet) |
| Chân 44 | NC — Not connected (per datasheet) |
Ứng dụng tiêu biểu
PIC16C74B-20I/L phù hợp cho 6 Áp dụngs: Industrial Process Control Systems, Motor Control and PWM Drive, Sensor Interfacing and Data Acquisition, Building Automation and HVAC Control, Embedded Instrumentation and Test Equipment, Legacy Industrial Retrofit Systems.
Industrial Process Control Systems
The PIC16C74B-20I/L fits industrial process control because its 8-channel 8-bit ADC directly interfaces with 4-20 mA current loop sensors, thermocouples (via op-amp front-end), and pressure transducers without external signal conditioning ICs. Its 20 MHz clock and 200 ns instruction cycle execute PID control loops at update rates up to 5 kHz, sufficient for thermal regulation and flow control. The industrial temperature range of -40 C to +85 C supports factory-floor deployments. The 33 I/O lines drive relays, solenoids, and indicator LEDs directly when current is limited. Three timers generate precise PWM outputs for valve and damper actuators, while the USART communicates with HMI panels. The OTP memory protects production firmware from unauthorized field modifications, important in regulated process industries.
Được đề xuất
Motor Control and PWM Drive
The PIC16C74B-20I/L drives small DC motors and stepper motor stages using its two Capture/Compare/PWM modules, which generate complementary PWM outputs with programmable dead-time insertion up to 20 kHz switching frequency. The 20 MHz instruction cycle supports closed-loop PID updates at 10 kHz, adequate for spindle speed regulation in benchtop equipment. Quadrature encoder feedback is decoded via the CCP capture inputs for position control. The 8-bit ADC samples motor current through shunt resistors for torque limiting and stall detection. With 33 I/O lines, the MCU coordinates direction logic, brake drivers, and limit-switch interlocks simultaneously. The wide 4.0 V to 5.5 V supply range tolerates noisy industrial DC bus rails typical of motor drive cabinets.
Được đề xuất
Sensor Interfacing and Data Acquisition
The PIC16C74B-20I/L serves sensor-hub applications because its 8-channel 8-bit ADC multiplexes up to eight analog sensors - temperature, pressure, humidity, light, gas - through a single MCU, minimizing PCB area. The I2C/SPI MSSP port expands the channel count by interfacing external digital sensors (accelerometers, gyroscopes). The USART streams digitized sensor data to a host controller or PC at 115.2 kbps. With 192 bytes of RAM and 7 KB OTP, the firmware can implement calibration tables, linearization polynomials, and digital filtering (moving average, IIR) on-board. The industrial temperature rating and ceramic PLCC package suit long-life installations in unattended data-logger deployments such as weather stations and remote monitoring nodes.
Được đề xuất
Building Automation and HVAC Control
The PIC16C74B-20I/L fits building automation controllers because it integrates analog sensing (via 8-channel ADC), digital I/O (33 lines for relay switching), and serial communication (USART for BACnet/Modbus gateways) in a single chip. Its 4.0 V to 5.5 V supply operates from 5 V regulated rails common in HVAC control panels. The PWM modules drive damper actuators and variable-speed fan motors with closed-loop feedback from temperature sensors. Three timers schedule daily HVAC cycles (occupied/unoccupied modes) without an external RTC. The OTP memory locks in certified control algorithms that cannot be field-tampered with, important for energy code compliance. Industrial temperature range ensures reliable operation in mechanical rooms and rooftop unit enclosures.
Được đề xuất
Embedded Instrumentation and Test Equipment
The PIC16C74B-20I/L functions as the main controller in benchtop instruments where its 20 MHz clock drives real-time measurement displays and keypad menu navigation. The SPI port interfaces LCD graphic displays and digital potentiometers, while the I2C bus reads EEPROM calibration constants at startup. The USART outputs measurement data to a PC for logging and analysis. Three timers generate accurate time bases for frequency counters and pulse-width measurements. The 8-bit ADC digitizes analog inputs up to 100 kSPS aggregate rate. The industrial temperature rating supports laboratory and field service environments, while OTP memory protects proprietary calibration algorithms from copying during service or repair. The 44-PLCC package provides reliable socket-mounting in test fixtures.
Được đề xuất
Legacy Industrial Retrofit Systems
The PIC16C74B-20I/L is the preferred replacement for obsolete or end-of-life microcontrollers in legacy industrial equipment because it shares the 44-PLCC J-Lead footprint with many older 8-bit designs from the 1990s. The OTP memory matches the production firmware model used in legacy installations. With 7 KB program memory and 192 bytes RAM, it is code-compatible with earlier PIC16C7x designs through the standard 35-instruction RISC set, simplifying firmware porting. The 33 I/O lines map directly to peripheral replacement boards. Microchip's continued active lifecycle status means long-term support is available for industrial customers maintaining 15-20 year equipment lifecycles. The ceramic windowed package allows UV erasure during development iteration before final production programming.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PIC16C74B-20I/L — 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 | PIC16C74B-20/L | PIC16C74B-04I/L | PIC16C74B-04E/L | PIC16C74A-20I/L | PIC16C67-20I/PQ |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-PLCC (J-Lead) | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same |
| Max Clock Frequency | 20 MHz | 20 MHz | 4 MHz | 4 MHz | 20 MHz | 20 MHz |
| Program Memory | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP |
| RAM Size | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| ADC Channels | 8 x 8-bit | 8 x 8-bit | 8 x 8-bit | 8 x 8-bit | 8 x 8-bit | 0 (no ADC) |
| Operating Temperature | -40 C to +85 C (Industrial) | 0 C to +70 C (Commercial) | -40 C to +85 C (Industrial) | -40 C to +125 C (Extended) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) |
| Supply Voltage | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V |
Bảo phân biệt quan trọng
- Industrial temperature grade in standard product offering (vsPIC16C74B-20/L)
- Maximum 20 MHz clock performance within PIC16C74B family (vsPIC16C74B-04I/L)
- 8-channel 8-bit ADC integrated on-chip (vsPIC16C67-20I/PQ)
- Newer silicon revision (B) with improved electrical characteristics (vsPIC16C74A-20I/L)
Ghi chú thiết kế
The PIC16C74B-20I/L requires a regulated 5 V supply within 4.0 V to 5.5 V. Place a 100 nF ceramic decoupling capacitor within 5 mm of each VDD pin and a 10 uF bulk tantalum or aluminum electrolytic capacitor at the board entry point. For noisy industrial environments, add a ferrite bead in series with the VDD supply line to suppress conducted EMI from motor drives and switching relays. The MCLR (pin 1) should be tied to VDD through a 10 kohm pull-up resistor with a 100 nF capacitor to ground for power-on reset delay. Avoid long VDD traces that act as antennas - keep the supply loop area minimal.
The 44-PLCC J-Lead package requires a socket (e.g., 44-pin PLCC IC socket) for development iteration, since the ceramic windowed variant is intended for UV erasure during prototyping. For production, wave or reflow soldering is acceptable but ensure land pattern matches JEDEC PLCC-44 standard. Keep clock traces (OSC1/OSC2) short, less than 25 mm, and surround with a ground guard ring to reduce EMI pickup. Place the crystal or resonator within 10 mm of the OSC pins and connect the load capacitors (typically 15-33 pF) directly to ground. Route analog signals (RA0-RA5) away from digital switching traces to minimize ADC noise coupling.
OTP (One-Time Programmable) memory CANNOT be erased or rewritten once programmed. Verify your firmware completely using the windowed ceramic package (UV-erasable during development) before committing to production OTP programming. The configuration bits (fuses) control oscillator mode, watchdog timer, code protection, and brown-out voltage - incorrect settings can lock the device or cause erratic behavior. When using the ADC, the acquisition time must be accounted for by setting the appropriate Tad value based on the system clock. For interrupt-driven designs, save and restore the W register and STATUS register in the interrupt service routine to prevent context corruption. Do not exceed the absolute maximum ratings of 7.0 V on VDD or current per pin of 25 mA.
Thông tin tuân thủ
RoHS/REACH/lead-free status not explicitly stated in provided data. Windowed ceramic CERDIP/PLCC packages are often non-RoHS; verify with Microchip directly. Conflict minerals compliance per Microchip standard policy.
