PIC16C74B-04I/PQ - 8-Bit 4MHz OTP MCU, 7KB, 44-MQFP | Microchip
MPN: PIC16C74B-04I/PQ ✗ Cuối đờiPIC16C74B-04I/PQ Tóm tắt
An 8-bit microcontroller is a small computer-on-a-chip that combines a CPU, RAM, non-volatile program memory, and peripherals on a single die. The PIC16C74B belongs to the PIC mid-range architecture hierarchy (8-bit PIC -> PIC16 family -> PIC16C7x sub-family), sits within the broader Microcontroller (MCU) category, and is part of Integrated Circuits > Microcontrollers. Mid-range PIC16 devices use a 14-bit instruction word and a RISC core with only 35 single-word instructions, providing deterministic timing and very low power consumption.
Key features include 8 channels of 8-bit Analog-to-Digital conversion, 33 digital I/O pins with 25 mA sink/source drive, two additional timers, two Capture/Compare/PWM modules, a synchronous serial port configurable as 3-wire SPI or 2-wire I2C, and a USART. Wide operating voltage spans 2.5 V to 6.0 V, with typical standby current of 1 uA at 3 V/32 kHz and 15 uA at 5 V/4 MHz, making the part suitable for both line-powered and battery-backed designs.
The architecture pairs a Harvard RISC core with 5 MIPS peak throughput at 4 MHz, an internal 8-bit data bus, and a 14-bit program bus. The OTP program memory is windowed for prototype development and field-programmed via Microchip's standard ICSP interface, while the EPROM-style die allows short reprogram cycles during engineering.
Typical applications include industrial control systems, instrumentation front-ends with on-chip ADC, motor-control PWM drivers, embedded sensor hubs, and legacy PIC16C designs being maintained or re-spun. The combination of USART, SPI/I2C and an 8-channel ADC makes the part a versatile single-chip solution for analog-dominated 5 V systems.
When designing with this MCU, budget for OTP one-time programming: code changes require new parts for production. Provide a robust decoupling network (100 nF + 10 uF) near VDD and use the MCLR reset circuit with the recommended 10 kohm pull-up.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho PIC16C74B-04I/PQ — 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-04I/PQ (cùng hình factor và footprint) — khác nhau ở Serial Interfaces, Package, Timers, Core Architecture, Operating Temperature.
PIC16C74B-04/PQ
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74B-04I/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74A-04I/PQ
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74B-04E/PQ
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16F74-I/PQ
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC16C74B-04I/PQ Tỷ lệ tối đa & tính chất điện
| Core Architecture | PIC16CXX mid-range 8-bit RISC |
| Instruction Set | 35 single-word instructions, 14-bit word |
| CPU Speed | 4 MHz (200 ns instruction cycle) |
| Program Memory | 7 KB (4K x 14) OTP |
| Data RAM | 192 bytes |
| I/O Pins | 33 digital I/O |
| ADC | 8 channels, 8-bit |
| Timers | 3 (Timer0, Timer1, Timer2) |
| Capture/Compare/PWM | 2 CCP modules |
| Serial Interfaces | 1x SPI/I2C (SSP) + 1x USART |
| Operating Voltage | 2.5 V to 6.0 V |
| I/O Sink/Source Current | 25 mA / 25 mA |
| Standby Current (3V, 32 kHz) | 1 uA typical |
| Operating Current (5V, 4 MHz) | 15 uA typical |
| Hộp | 44-MQFP (10x10 mm) |
| Nhiệt độ hoạt động | -40C to +85C (Industrial) |
| Kiểu lắp đặt | Surface Mount |
Cấu hình chân PIC16C74B-04I/PQ
| Chân 1 | MCLR — Master Clear (reset) input, active low |
| Chân 2 | OSC1 — Oscillator input / external clock input |
| Chân 3 | OSC2 — Oscillator output |
| Chân 4 | RA0/AN0 — Port A bit 0 / analog channel 0 |
| Chân 5 | RA1/AN1 — Port A bit 1 / analog channel 1 |
| Chân 6 | RA2/AN2 — Port A bit 2 / analog channel 2 |
| Chân 7 | RA3/AN3/VREF — Port A bit 3 / analog channel 3 / VREF input |
| Chân 8 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Chân 9 | RA5/AN4/SS — Port A bit 5 / analog channel 4 / SPI slave select |
| Chân 10 | VSS — Ground |
| Chân 11 | VDD — Positive supply voltage |
| Chân 12 | RB0/INT — Port B bit 0 / external interrupt |
| Chân 13 | RB1 — Port B bit 1 |
| Chân 14 | RB2 — Port B bit 2 |
| Chân 15 | RB3 — Port B bit 3 |
| Chân 16 | RB4 — Port B bit 4 |
| Chân 17 | RB5 — Port B bit 5 |
| Chân 18 | RB6/PGC — Port B bit 6 / ICSP clock |
| Chân 19 | RB7/PGD — Port B bit 7 / ICSP data |
| Chân 20 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer1 oscillator out / clock in |
| Chân 21 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator in / CCP2 |
| Chân 22 | RC2/CCP1 — Port C bit 2 / CCP1 |
| Chân 23 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Chân 24 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Chân 25 | RC5/SDO — Port C bit 5 / SPI data out |
| Chân 26 | RC6/TX/CK — Port C bit 6 / USART TX / clock |
| Chân 27 | RC7/RX/DT — Port C bit 7 / USART RX / data |
| Chân 28 | VSS — Ground |
| Chân 29 | VDD — Positive supply voltage |
| Chân 30 | RD0/PSP0 — Port D bit 0 / Parallel Slave Port bit 0 |
| Chân 31 | RD1/PSP1 — Port D bit 1 / Parallel Slave Port bit 1 |
| Chân 32 | RD2/PSP2 — Port D bit 2 / Parallel Slave Port bit 2 |
| Chân 33 | RD3/PSP3 — Port D bit 3 / Parallel Slave Port bit 3 |
| Chân 34 | RD4/PSP4 — Port D bit 4 / Parallel Slave Port bit 4 |
| Chân 35 | RD5/PSP5 — Port D bit 5 / Parallel Slave Port bit 5 |
| Chân 36 | RD6/PSP6 — Port D bit 6 / Parallel Slave Port bit 6 |
| Chân 37 | RD7/PSP7 — Port D bit 7 / Parallel Slave Port bit 7 |
| Chân 38 | AVSS — Analog ground |
| Chân 39 | AVDD — Analog positive supply |
| Chân 40 | RE0/RD — Port E bit 0 / Read control for PSP |
| Chân 41 | RE1/WR — Port E bit 1 / Write control for PSP |
| Chân 42 | RE2/CS — Port E bit 2 / Chip select for PSP |
| Chân 43 | NC — Not connected (per datasheet) |
| Chân 44 | NC — Not connected (per datasheet) |
Ứng dụng tiêu biểu
PIC16C74B-04I/PQ phù hợp cho 6 Áp dụngs: Industrial Control PLCs, Motor Control PWM Drivers, Sensor Hub / Data Acquisition, Embedded Instrumentation Front-End, HVAC Control Boards, Legacy Embedded Maintenance.
Industrial Control PLCs
The PIC16C74B-04I/PQ fits industrial PLC front-ends because its 8-channel 8-bit ADC multiplexes directly onto analog sensors (temperature, pressure, 4-20 mA loops) while its 25 mA I/O drive sources and sinks relay coils and LED indicators without external buffers. Industrial -40C to +85C operation, USART for Modbus RTU over RS-485, and SPI/I2C for digital sensor extension all integrate on one die. Two CCP modules generate PWM for proportional valve or motor-speed control. The OTP memory locks firmware for code-security-sensitive installations. Power consumption is 15 uA active at 5 V/4 MHz and 1 uA standby at 3 V/32 kHz, suiting always-on panel instrumentation.
Được đề xuất
Motor Control PWM Drivers
The PIC16C74B-04I/PQ drives brushed DC and stepper motors via its two Capture/Compare/PWM modules delivering 10-bit PWM resolution at up to ~20 kHz carrier frequency. The 4 MIPS throughput computes PI speed loops with adequate headroom for trapezoidal commutation of small BLDC motors. The 25 mA sink/source I/O eliminates predriver FETs for sub-1 A loads. Hardware timers (Timer0/1/2) provide encoder feedback capture and tick generation. Industrial -40C to +85C operation suits HVAC fan and pump controllers, while the OTP memory secures proprietary motor-tuning firmware from reverse engineering.
Được đề xuất
Sensor Hub / Data Acquisition
The PIC16C74B-04I/PQ acts as a low-cost sensor hub for 4-20 mA loops, thermocouples (with external amp), and digital SPI/I2C sensors because its 8-channel ADC plus synchronous serial port covers mixed-signal designs in a single chip. The 192-byte RAM holds rolling buffers of 8 channels sampled at low rates, with USART forwarding data to a host controller or HMI display. Industrial temperature rating and 2.5-6.0 V VDD tolerate 5 V analog sensor rails directly. The 4 MIPS core runs polynomial correction algorithms for thermocouple linearization. OTP memory locks calibration constants in production.
Được đề xuất
Embedded Instrumentation Front-End
The PIC16C74B-04I/PQ provides a complete front-end panel-meter or process-indicator controller: ADC channels read voltage/current transducers, PWM drives a 4-20 mA loop output via an external op-amp, and the USART outputs readings to a remote display. Industrial temperature range supports panel-mount installations. Two CCP modules generate precise PWM for proportional control loops. The OTP memory is ideal for shipping calibrated instruments with locked firmware. With 7 KB OTP and 192 B RAM, the part handles linearization tables, lookup tables for thermistors, and simple menu/UI logic on a small character LCD.
Được đề xuất
HVAC Control Boards
The PIC16C74B-04I/PQ is well-suited to HVAC damper/valve controllers where multiple analog inputs (temperature, humidity, pressure) and PWM outputs (fan speed, valve position) are required. The 8-channel ADC handles several NTC/PTC thermistors with software linearization; two CCP modules drive TRIAC phase-control circuits or solid-state relay PWM at low frequency. The 25 mA I/O directly interfaces with opto-isolated TRIAC drivers. The -40C to +85C industrial rating covers unconditioned rooftop unit enclosures. OTP memory locks OEM calibration values and prevents unauthorized firmware tampering.
Được đề xuất
Legacy Embedded Maintenance
The PIC16C74B-04I/PQ serves as maintenance stock for industrial systems deployed in the late 1990s and 2000s, where the PCB is hard-wired for a 44-MQFP footprint and rewrites to flash silicon would require a board respin. Its drop-in compatibility with PIC16F74 and PIC16C74B-04/PQ simplifies field replacements; technicians can swap the OTP part for the flash equivalent when in-system reprogramming is feasible. The PIC16C instruction-set and peripheral set match modern mid-range PIC16F variants, allowing firmware recompilation without source changes.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PIC16C74B-04I/PQ — 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-04/PQ | PIC16C74B-04I/L | PIC16C74A-04I/PQ | PIC16C74B-04E/PQ | PIC16F74-I/PQ |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-MQFP (10x10 mm) | 44-MQFP (10x10 mm) - identical | 44-MQFP - footprint equivalent | 44-MQFP (10x10 mm) - identical | 44-MQFP (10x10 mm) - identical | 44-MQFP (10x10 mm) - identical |
| Program Memory | 7 KB (4K x 14) OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 4 KB Flash |
| RAM | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes |
| Max CPU Speed | 4 MHz / 5 MIPS | 4 MHz / 5 MIPS | 4 MHz / 5 MIPS | 4 MHz / 5 MIPS | 4 MHz / 5 MIPS | 20 MHz / 5 MIPS (Flash variant) |
| ADC | 8 ch x 8-bit | 8 ch x 8-bit | 8 ch x 8-bit | 8 ch x 8-bit (rev A errata) | 8 ch x 8-bit | 8 ch x 8-bit |
| Operating Temperature | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +125C (Extended) | -40C to +85C (Industrial) |
| Memory Type | OTP (one-time programmable) | OTP | OTP | OTP | OTP | Flash (re-programmable) |
| Lifecycle | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Active |
Bảo phân biệt quan trọng
- OTP code security with industrial temperature range (vsPIC16F74-I/PQ)
- Higher program memory density at same speed grade (vsPIC16C73B-04I/SP)
- Wider operating voltage range than PIC16F1X successors (vsPIC16F877A-I/P)
Ghi chú thiết kế
Decouple VDD/AVDD with a 100 nF ceramic capacitor placed within 5 mm of each supply pin, plus a bulk 10 uF tantalum or ceramic on the main 5 V rail. The PIC16C74B-04I/PQ has separate digital VDD/VDD and analog AVDD/AVSS pins (pins 11/29/38/39); connect AVDD to VDD through a ferrite bead or 10 ohm resistor and AVSS to VSS with a star-ground topology. Operating current is 15 uA typical at 5 V/4 MHz and standby current drops to 1 uA at 3 V/32 kHz - budget decoupling accordingly for low-frequency sleep modes.
The PIC16C74B is OTP (one-time programmable) - code changes after programming require physical replacement of the chip, which is expensive in production. Plan firmware development on a windowed PIC16C74B JW or PIC16F74 equivalent before committing to OTP. Also note the Parallel Slave Port (Port D + RE0/RE1/RE2) shares pins with general-purpose I/O - if PSP is enabled in software, those pins lose their digital I/O function. Verify MCLR is pulled high through 10 kohm to VDD and never left floating, which causes random resets.
For the 44-MQFP package (10x10 mm, 0.8 mm pitch), use a 4-layer PCB with continuous ground plane under the IC to minimize EMI and provide thermal spreading. Place the 4 MHz crystal (or ceramic resonator) within 10 mm of OSC1/OSC2 (pins 2-3) and guard the traces with a ground ring. Add a 1 Mohm parallel resistor across the crystal for fast-startup oscillator designs. Route ICSP pins RB6/PGC and RB7/PGD to a 6-pin header (with VDD/VSS/MCLR) for in-circuit programming access - this is essential even though the part is OTP, for prototype-stage programming before production.
The PIC16C74B-04I/PQ's 25 mA source/sink capability allows direct drive of relays, LEDs and optocouplers without buffers; however, switching inductive loads requires flyback diodes (1N4148 or Schottky) across coils to prevent latch-up. For SPI communication above 1 MHz, add 10 kohm pull-ups on SCK/SDO and series 100 ohm termination on clock traces to reduce ringing. The ADC is 8-bit and tolerates source impedances up to 10 kohm - add 100 nF bypass on analog inputs if the source impedance exceeds 5 kohm to prevent ADC sampling errors.
Thông tin tuân thủ
RoHS and lead-free status not confirmed in verified web data; this is a 1990s-2000s era OTP MCU that may predate RoHS. AEC-Q100 not qualified - automotive applications should consider PIC16F877A-I/P or PIC18F variants.
