PIC16C74BT-20E/L - 8-Bit 20MHz OTP MCU 7KB PLCC-44 | Microchip
MPN: PIC16C74BT-20E/L ✗ Cuối đờiPIC16C74BT-20E/L Tóm tắt
A microcontroller (MCU) is a single-chip computer that integrates a CPU, memory (program + RAM), and programmable I/O peripherals onto one silicon die. The PIC16CXX mid-range family uses a Harvard architecture with separate program and data buses, a 14-bit instruction word, and a RISC instruction set, executing one instruction per instruction cycle (4 clock cycles) for predictable deterministic timing. Within the broader semiconductor hierarchy, an MCU belongs to the logic IC family -> microprocessor -> embedded controller -> mixed-signal SoC.
Key features include 33 digital I/O pins, two 8-bit and three 16-bit timer/counter modules, a 5-channel 8-bit ADC, two analog comparators, a Universal Synchronous/Asynchronous Receiver/Transmitter (USART/SCI), a Serial Peripheral Interface (SPI), and an Inter-Integrated Circuit (I2C) bus. The OTP program memory allows one-time programming by the developer, distinguishing this part from UV-erasable EPROM variants. Operating voltage ranges from 4.0V to 6.0V, suiting 5V industrial and automotive designs.
The PIC16C74B architecture employs a 14-bit instruction pipeline with an 8-level hardware stack, supporting interrupt-driven designs with prioritized vectored interrupts. Brown-out Reset (BOR) and Power-on Reset (POR) circuitry protect against unstable supply conditions, while the Watchdog Timer (WDT) with its own on-chip RC oscillator provides system recovery from software lockups - critical for automotive and industrial environments where firmware reliability is non-negotiable.
Typical applications include automotive body electronics, industrial control subsystems, sensor interface modules, HVAC controllers, and legacy embedded systems requiring field-programmable OTP at production volume. The 20MHz instruction throughput and 5-channel ADC make it well-suited for closed-loop motor control and PID-based process regulation.
When designing with the PIC16C74B, ensure the operating supply stays within 4.0V to 6.0V and that decoupling capacitors (typically 0.1uF ceramic) are placed within 5mm of VDD/SS pins. The PLCC-44 socket allows field replacement and in-circuit programming, but OTP memory means firmware must be fully verified before production programming.
Bộ thay thế dễ dàng lắp đặt cho PIC16C74BT-20E/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 PIC16C74BT-20E/L (cùng hình factor và footprint) — khác nhau ở Core Architecture, Timers, Package, Program Memory Size, Maximum Clock Frequency.
PIC16C74BT-20/L
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC16C74BT-20I/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74B-20/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74B-04E/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16F74-I/L
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16C74BT-20E/L Tỷ lệ tối đa & tính chất điện
| Core Architecture | PIC16CXX mid-range 8-bit RISC |
| Program Memory Size | 7 KB (4K x 14) OTP |
| RAM Size | 192 x 8 bytes |
| Tần số xung maksimum | 20 MHz |
| Instruction Cycle Time | 200 ns (at 20 MHz) |
| Operating Voltage (VDD) | 4.0 V to 6.0 V |
| I/O Pins | 33 |
| Timers | 2 x 8-bit, 3 x 16-bit |
| ADC | 5-channel, 8-bit |
| Analog Comparators | 2 |
| Communication Interfaces | USART/SCI, SPI, I2C |
| Khoảng nhiệt độ hoạt động | -40 C to +125 C (automotive grade E) |
| Hộp | 44-pin PLCC (16.59 x 16.59 mm), J-bend leads |
| Kiểu lắp đặt | Surface Mount (PLCC socket compatible) |
| Lead Form | J-Bend (PLCC) |
| Brown-out Reset | Yes |
| Watchdog Timer | Yes (independent on-chip RC oscillator) |
| Program Memory Type | OTP (One-Time Programmable) |
Cấu hình chân PIC16C74BT-20E/L
| Chân 1 | RA2/AN2/VREF- — PORTA bit 2 / Analog input 2 / ADC VREF- |
| Chân 2 | RA3/AN3/VREF+ — PORTA bit 3 / Analog input 3 / ADC VREF+ |
| Chân 3 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Chân 4 | RA5/AN4/SS — PORTA bit 5 / Analog input 4 / SPI slave select |
| Chân 5 | RE0/RD/AN5 — PORTE bit 0 / Read signal for PSP / Analog input 5 |
| Chân 6 | RE1/WR/AN6 — PORTE bit 1 / Write signal for PSP / Analog input 6 |
| Chân 7 | RE2/CS/AN7 — PORTE bit 2 / Chip select for PSP / Analog input 7 |
| Chân 8 | VDD — Positive supply (4.0V to 6.0V) |
| Chân 9 | VSS — Ground reference |
| Chân 10 | OSC1/CLKIN — Crystal oscillator input / external clock input |
| Chân 11 | OSC2/CLKOUT — Crystal oscillator output / clock output (Fosc/4) |
| Chân 12 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Chân 13 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / Capture-Compare-PWM 2 |
| Chân 14 | RC2/CCP1 — PORTC bit 2 / Capture-Compare-PWM 1 |
| Chân 15 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Chân 16 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Chân 17 | RC5/SDO — PORTC bit 5 / SPI data out |
| Chân 18 | RC6/TX/CK — PORTC bit 6 / USART transmit / USART clock |
| Chân 19 | RC7/RX/DT — PORTC bit 7 / USART receive / USART data |
| Chân 20 | VSS — Ground reference |
| Chân 21 | RD0/PSP0 — PORTD bit 0 / Parallel Slave Port bit 0 |
| Chân 22 | RD1/PSP1 — PORTD bit 1 / Parallel Slave Port bit 1 |
| Chân 23 | RD2/PSP2 — PORTD bit 2 / Parallel Slave Port bit 2 |
| Chân 24 | RD3/PSP3 — PORTD bit 3 / Parallel Slave Port bit 3 |
| Chân 25 | RD4/PSP4 — PORTD bit 4 / Parallel Slave Port bit 4 |
| Chân 26 | RD5/PSP5 — PORTD bit 5 / Parallel Slave Port bit 5 |
| Chân 27 | RD6/PSP6 — PORTD bit 6 / Parallel Slave Port bit 6 |
| Chân 28 | RD7/PSP7 — PORTD bit 7 / Parallel Slave Port bit 7 |
| Chân 29 | VSS — Ground reference |
| Chân 30 | VDD — Positive supply (4.0V to 6.0V) |
| Chân 31 | RB0/INT — PORTB bit 0 / External interrupt |
| Chân 32 | RB1 — PORTB bit 1 |
| Chân 33 | RB2 — PORTB bit 2 |
| Chân 34 | RB3 — PORTB bit 3 |
| Chân 35 | RB4 — PORTB bit 4 (interrupt-on-change) |
| Chân 36 | RB5 — PORTB bit 5 (interrupt-on-change) |
| Chân 37 | RB6/PGC — PORTB bit 6 / In-circuit debugger clock |
| Chân 38 | RB7/PGD — PORTB bit 7 / In-circuit debugger data |
| Chân 39 | RA0/AN0 — PORTA bit 0 / Analog input 0 |
| Chân 40 | RA1/AN1 — PORTA bit 1 / Analog input 1 |
| Chân 41 | MCLR/VPP — Master clear reset / Programming voltage input |
| 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
PIC16C74BT-20E/L phù hợp cho 6 Áp dụngs: Automotive Body Control Modules, Industrial HVAC Control, Sensor Interface Front-Ends, Motor Speed Controllers, Vending Machine Controllers, Legacy Industrial PLC I/O Modules.
Automotive Body Control Modules
The PIC16C74BT-20E/L's automotive-grade -40C to +125C operating range and 20MHz throughput make it a strong fit for automotive body control modules managing door locks, window lifters, seat position memory, and interior lighting. The 5-channel 8-bit ADC reads potentiometric position sensors for seat and mirror adjustment, while the 33 digital I/O pins drive relay drivers and switch-matrix keypad inputs. Its 7KB OTP program memory holds fixed-function body-control firmware, and the integrated CAN-less USART/SPI/I2C stack supports communication with body domain controllers. The automotive E temperature grade handles under-hood thermal stress without derating.
Được đề xuất
Industrial HVAC Control
In HVAC fan-coil and rooftop-unit controllers, the PIC16C74BT-20E/L provides the deterministic 200ns instruction cycle needed for closed-loop temperature regulation with PID control running at 1 kHz update rates. The 5-channel ADC samples thermistor inputs (return air, supply air, outdoor, coil, and setpoint potentiometer), while two 16-bit timers drive triac phase-angle firing for variable-speed blower motors. The 33 I/O pins interface with thermostat keypads, mode switches, and 7-segment displays. OTP memory suits fixed-firmware production runs where per-unit programming cost dominates over flexibility.
Được đề xuất
Sensor Interface Front-Ends
The PIC16C74BT-20E/L serves as a digital front-end for legacy 4-20 mA and 0-10V industrial sensor transmitters, multiplexing multiple analog channels through its 5-input ADC, linearizing the result, and outputting a calibrated value via the USART in Modbus RTU format. The 20MHz clock sustains 9600/19200 baud Modbus traffic without CPU saturation, leaving cycles for sensor linearization math. The 192-byte RAM is adequate for Modbus packet buffers and a small coefficient table, and the 7KB OTP holds the calibration and protocol stack. The automotive E temperature grade suits outdoor or cabinet-mounted installations.
Được đề xuất
Motor Speed Controllers
For low-voltage brushed DC and universal motor speed controllers, the PIC16C74BT-20E/L generates PWM at up to 20MHz timer resolution, enabling 10-bit PWM at 19.5 kHz for quiet BLDC commutation or 8-bit PWM at 78 kHz for ultrasonic-frequency silent drives. The three 16-bit timers handle quadrature encoder input for closed-loop velocity feedback, while the 5-channel ADC monitors motor current via shunt resistor, supply voltage, and temperature. OTP memory locks the motor control algorithm at production. The automotive temperature grade handles under-hood or unventilated enclosure environments without thermal derating.
Được đề xuất
Vending Machine Controllers
The PIC16C74BT-20E/L's 33 I/O pins accommodate multi-currency coin acceptor interfaces, MDB peripheral bus, vend-mechanism actuator drivers, and 7-segment or character-LCD user displays. The 7KB OTP memory stores pricing tables, audit logs, and vending state machine firmware that is rarely updated in the field. The 20MHz instruction throughput handles real-time pulse counting from coin validators at 50 kHz maximum without dropped counts. Two analog comparators enable zero-cross detection for triac-driven refrigeration compressors. OTP ensures fixed production firmware, deterring field tampering and reducing EEPROM-related counterfeit risk.
Được đề xuất
Legacy Industrial PLC I/O Modules
In distributed I/O blocks that interface with older PLCs over RS-232 or RS-485, the PIC16C74BT-20E/L acts as a slave protocol converter, digitizing 4-20 mA inputs through the 5-channel ADC and latching output states through the 33 digital I/O pins. The USART peripheral supports 9-bit multiprocessor communication used by some legacy PLC protocols, while the SPI peripheral interfaces with shift-register-based digital I/O expansion. The OTP memory holds the fixed protocol translator firmware. The automotive E temperature grade is suitable for factory-floor cabinets with elevated ambient temperatures from adjacent motor drives.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PIC16C74BT-20E/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 | PIC16C74BT-20/L | PIC16C74BT-20I/L | PIC16C74B-20/L | PIC16C74B-04E/L | PIC16F74-I/L |
|---|---|---|---|---|---|---|
| Package | 44-PLCC | 44-PLCC - same | 44-PLCC - same | 44-PLCC - same | 44-PLCC - same | 44-PLCC - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core | PIC16 8-bit RISC | PIC16 8-bit RISC - same | PIC16 8-bit RISC - same | PIC16 8-bit RISC - same | PIC16 8-bit RISC - same | PIC16 8-bit RISC - same |
| Max Clock Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 4 MHz (-80%) | 20 MHz |
| Program Memory | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB Flash (reprogrammable) |
| Operating Temperature | -40C to +125C (E grade) | 0C to +70C (commercial) | -40C to +85C (industrial) | 0C to +70C (commercial) | -40C to +125C (E grade) | -40C to +85C (industrial) |
| ADC Channels | 5 x 8-bit | 5 x 8-bit | 5 x 8-bit | 5 x 8-bit | 5 x 8-bit | 5 x 8-bit |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| Lifecycle Status | Obsolete | Obsolete | Obsolete | Obsolete | Obsolete | Active |
Bảo phân biệt quan trọng
- Automotive E temperature grade support (-40C to +125C) (vsPIC16C74B-20/L)
- OTP memory for fixed-function production firmware (vsPIC16F74-I/L)
- Higher clock speed headroom than the -04 variant (vsPIC16C74B-04E/L)
Ghi chú thiết kế
The PIC16C74BT-20E/L requires a regulated 4.0V to 6.0V supply; typical designs use a 7805 linear regulator or equivalent. Place a 0.1uF ceramic decoupling capacitor within 5mm of the VDD pin (pin 8) and VSS pin (pin 9), and add a bulk 10uF electrolytic at the regulator output to suppress load-transient dips. The Brown-out Reset (BOR) circuit holds the MCU in reset when VDD falls below ~4.0V, preventing code execution from corrupt memory states during power-down. Avoid noise on the MCLR/VPP pin (pin 41) by tying it to VDD through a 10kohm resistor with a 0.1uF decoupling cap directly at the pin - any noise here can spuriously trigger resets or interrupt programming mode.
The PLCC-44 package can be socketed for field upgradeability (use a 44-pin PLCC through-hole socket such as Aries 44-6518-10), or soldered directly to SMT pads with J-bend leads. When using a socket, route high-frequency signals away from the socket body to minimize parasitic inductance. Crystal traces on pins 10 (OSC1) and 11 (OSC2) should be kept short (<10mm) and guarded with a ground pour to reduce EMI susceptibility. For RS-232 driver chips, keep the charge-pump capacitors within 2mm of the driver IC pins, and route the driver outputs perpendicular to the MCU's RX/TX traces to minimize coupling.
OTP program memory cannot be erased or rewritten - verify all firmware on a flash-based PIC16F74 prototype before committing to OTP production programming. LVP (Low-Voltage Programming) mode via the PGM pin and standard ICSP mode via RB6/RB7 (PGC/PGD) are mutually exclusive configurations; the CONFIG word LVP bit determines which mode is active, and a wrong choice can lock out programming access. The Watchdog Timer (WDT) is enabled by default in the configuration word - explicitly clear the WDTE bit if WDT is not needed, or service the CLRWDT instruction in all long-timeout loops to prevent unintended resets. Do not exceed 20 MHz at VDD below 4.5V; refer to the datasheet's VDD-vs-Frequency graph.
Thông tin tuân thủ
RoHS and REACH compliance status not explicitly stated in verified distributor data; the 44-pin PLCC package with J-bend leads typically uses tin-lead plating. Not AEC-Q100 qualified (automotive E temperature grade is industrial specification, not AEC-Q100). Lead-free and RoHS-compliant variants are not generally available for this obsolete OTP device.
