PIC16F876-20/SO - 8-bit 20MHz PIC MCU, 14KB Flash, 28-SOIC | Microchip
料号： PIC16F876-20/SO ✗ 停产| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $11.42 | $11.42 |
| 10 | $10.45 | $104.50 |
| 100 | $8.95 | $895.00 |
| 500 | $7.65 | $3,825.00 |
| 1,000 | $6.85 | $6,850.00 |
PIC16F876-20/SO 概述
A microcontroller (MCU) is a single-chip computer that integrates a CPU, non-volatile program memory, working RAM, and programmable peripherals. The 8-bit class represents the most widely deployed MCU tier, trading raw arithmetic width for deterministic timing, ultra-low cost per I/O, and decades of proven toolchain maturity. The PIC® mid-range architecture sits inside a broader taxonomy of microcontrollers -> 8-bit MCUs -> CMOS RISC MCUs -> flash-memory MCUs, and it remains one of the most deployed architectures in industrial, appliance, automotive aftermarket, and educational designs.
Key features of the PIC16F876-20/SO include 368 bytes of SRAM, an internal watchdog timer with its own on-chip RC oscillator, a programmable code-protection mechanism, an ICD (In-Circuit Debugger) interface, and a wide operating voltage range suitable for both 3.3 V and 5 V systems. The device supports in-circuit serial programming (ICSP), allowing firmware updates via just two pins without removing the part from the board.
Technically, the PIC16F876-20/SO uses a Harvard architecture with separate program and data buses, which lets a fetch and a read occur in parallel with execution. Its 14-bit instruction word is the defining trait of the mid-range family and provides a richer opcode space than 12-bit baseline PICs while preserving the same low-power CMOS implementation. The 'A' revision (PIC16F876A) later added internal improvements such as a wider ADC, but the original -20/SO remains pin-compatible and firmware-compatible for legacy code bases.
Typical applications include industrial control boards, sensor signal conditioning with A/D conversion, low-end motor control via the CCP/PWM modules, UART-connected sensor hubs, and educational/development kits where the PIC16 architecture is taught. The 28-SOIC footprint is the most common PCB variant of the PIC16F87x line.
When designing with this part, confirm that your firmware uses the original PIC16F876 silicon (not the 'A' revision) so the device-ID bits match and the ICSP programming algorithm is correct. The 20 MHz rating corresponds to a 20 MHz external oscillator and 200 ns instruction cycle; operation below this speed is supported, but the ADC acquisition time formula depends on Fosc and must be re-validated if the clock changes.
This page synthesizes distributor pricing, drop-in compatible alternatives sourced from web cross-reference data, and practical design notes that go beyond the manufacturer datasheet to help engineers evaluate the PIC16F876-20/SO for both new designs and legacy maintenance.
直接替换替代料： PIC16F876-20/SO ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： PIC16F876-20/SO （相同外形与封装尺寸） ——差异在于 ADC, Core Architecture, Data EEPROM, Program Memory (Flash), Timers.
快速对比工具——选择替代料号进行并排对比：
PIC16F876A-I/SO
✅ 直接替换📋 参考替代料（不在目录中）
PIC16F876T-20/SO
✅ 直接替换📋 参考替代料（不在目录中）
PIC16F873-20/SO
✅ 直接替换✓ 有现货
$5.1 / 个
查看数据手册 →PIC16F886-I/SO
✅ 直接替换📋 参考替代料（不在目录中）
PIC16F874A-I/SO
✅ 直接替换📋 参考替代料（不在目录中）
PIC16F876-20/SO 最大额定值与电气特性
| Core Architecture | PIC 8-bit RISC (mid-range, 14-bit instruction word) |
| Program Memory (Flash) | 14 KB (8K x 14 words) |
| RAM | 368 bytes |
| Data EEPROM | 256 bytes |
| Maximum CPU Clock | 20 MHz |
| Instruction Cycle | 200 ns @ 20 MHz |
| Instruction Set Size | 35 single-word instructions |
| I/O Pins | 22 |
| ADC | 10-bit, 5 channels (multiplexed) |
| Comparators | 2 |
| CCP/PWM Modules | 2 |
| Serial Interfaces | USART (asynchronous/synchronous), MSSP (SPI / I2C) |
| Timers | Timer0, Timer1, Timer2 |
| Watchdog Timer | Yes (with dedicated on-chip RC oscillator) |
| In-Circuit Programming/Debug | ICSP + ICD |
| 工作温度范围 | -40C to +85C (commercial grade -20/SO) |
| 封装 | 28-pin SOIC (SO) |
| 安装类型 | Surface Mount |
| Successor (recommended) | PIC16F886 / PIC16F876A-I/SO |
PIC16F876-20/SO 引脚配置
| 引脚 1 | MCLR/Vpp — Master Clear (Reset) input / ICSP programming voltage |
| 引脚 2 | RA0/AN0 — Port A bit 0 / analog input channel 0 |
| 引脚 3 | RA1/AN1 — Port A bit 1 / analog input channel 1 |
| 引脚 4 | RA2/AN2 — Port A bit 2 / analog input channel 2 |
| 引脚 5 | RA3/AN3/VREF+ — Port A bit 3 / analog input channel 3 / ADC positive reference |
| 引脚 6 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| 引脚 7 | RA5/AN4/SS — Port A bit 5 / analog input channel 4 / SPI slave select |
| 引脚 8 | Vss — Ground |
| 引脚 9 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| 引脚 10 | OSC2/CLKOUT — Oscillator crystal output / clock output (Fosc/4) |
| 引脚 11 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer1 oscillator output / Timer1 clock input |
| 引脚 12 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator input / CCP2 PWM output |
| 引脚 13 | RC2/CCP1 — Port C bit 2 / CCP1 PWM output |
| 引脚 14 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| 引脚 15 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| 引脚 16 | RC5/SDO — Port C bit 5 / SPI data out |
| 引脚 17 | RC6/TX/CK — Port C bit 6 / USART asynchronous transmit / I2C clock (MSSP) |
| 引脚 18 | RC7/RX/DT — Port C bit 7 / USART asynchronous receive / I2C data (MSSP) |
| 引脚 19 | Vss — Ground (secondary) |
| 引脚 20 | Vdd — Positive supply voltage |
| 引脚 21 | RB0/INT — Port B bit 0 / external interrupt input |
| 引脚 22 | RB1 — Port B bit 1 |
| 引脚 23 | RB2 — Port B bit 2 |
| 引脚 24 | RB3/PGM — Port B bit 3 / ICSP low-voltage programming enable |
| 引脚 25 | RB4 — Port B bit 4 |
| 引脚 26 | RB5 — Port B bit 5 |
| 引脚 27 | RB6/PGC — Port B bit 6 / ICSP clock (ICD) |
| 引脚 28 | RB7/PGD — Port B bit 7 / ICSP data (ICD) |
典型应用
PIC16F876-20/SO 适用于 7 应用s: Industrial Sensor Hub with A/D Conversion, Appliance Control Board (White Goods), Educational Microcontroller Trainer, Automotive Aftermarket Accessory Controller, Low-End Motor Speed Control (PWM Drive), Sensor-to-UART Bridge Module, Security Alarm Panel Logic Board.
Industrial Sensor Hub with A/D Conversion
The PIC16F876-20/SO is well-matched to industrial sensor-hub designs that aggregate multiple analog transducers and forward data over UART. Its 10-bit 5-channel ADC with 22 digital I/O handles thermocouple bridges, 4-20 mA loops, and digital switch arrays simultaneously, while the 14 KB Flash holds calibration tables, lookup curves, and a Modbus RTU slave stack. At 20 MHz the 200 ns instruction cycle completes ADC math and UART framing well within typical 100 ms scan windows, and the 368-byte SRAM is sufficient for buffering a few Modbus frames. The 28-SOIC footprint and ICSP allow field firmware updates without board removal, which matters for installed industrial nodes.
推荐
Appliance Control Board (White Goods)
The PIC16F876-20/SO is a classic fit for appliance control boards such as washing-machine controllers, dishwasher user-interface modules, and small HVAC dampers. Its 22 I/O pins drive seven-segment displays, keypad matrices, relay coils, and triac interfaces, while the 2 CCP/PWM modules generate variable-phase control signals for motor speed or valve actuation. The 256-byte EEPROM stores user-setpoints and last-cycle state across power cycles, and the 14 KB Flash holds the state-machine firmware with margin for country-specific variants. Wide operating temperature and the proven PIC mid-range reliability make it a default in legacy white-goods designs where PIC16F876A-I/SO is the active variant.
推荐
Educational Microcontroller Trainer
Universities and self-learners continue to use the PIC16F876-20/SO on breadboard trainer boards because the 28-SOIC footprint is easy to breakout and the 35-instruction mid-range instruction set is short enough to teach in one semester. Its 20 MHz speed and 200 ns instruction cycle make timing loops predictable for learning about interrupts, timer prescalers, and PWM duty cycles. The ICSP header on the trainer board allows students to load and debug code without removing the chip, and the 14 KB Flash accommodates multiple lab exercises including UART echo, ADC sampling, and CCP PWM motor control. The PIC16F84-10/P in the Site MPN list is the canonical stepping-stone before moving to PIC16F876-20/SO.
推荐
Automotive Aftermarket Accessory Controller
The PIC16F876-20/SO is found in automotive aftermarket modules such as auxiliary lighting controllers, alarm-system brain boards, and CAN-bridge translators that connect third-party accessories to the vehicle bus. The 20 MHz CPU, 10-bit ADC, and 22 I/O are sufficient to debounce switches, drive relay coils through Darlington arrays, and emulate simple CAN frames via bit-banged I/O or MSSP SPI to an external CAN transceiver. The -40C to +85C operating temperature matches automotive interior environments, and the 28-SOIC package withstands under-hood vibration when properly potted. For safety-critical applications a Q-graded part is required, but the PIC16F876-20/SO is appropriate for non-safety accessory controllers.
推荐
Low-End Motor Speed Control (PWM Drive)
The PIC16F876-20/SO drives small brushed DC motors and stepper-motor drivers via its two CCP/PWM modules, providing variable duty-cycle control of gate drivers or H-bridge logic. At 20 MHz the PWM period can be programmed from approximately 1.2 kHz to 200 kHz depending on prescaler, which covers most DC brushed and unipolar stepper applications. The 256-byte EEPROM stores calibrated ramp-up and ramp-down profiles for each user mode, and the 10-bit ADC reads back current-sense amplifiers to implement basic current limiting. For higher-current BLDC or three-phase applications a PIC18 or dsPIC derivative is preferred, but the PIC16F876-20/SO is the canonical choice in the 28-SOIC footprint for low-end single-motor modules.
推荐
Sensor-to-UART Bridge Module
The PIC16F876-20/SO serves as a compact sensor-to-UART bridge that aggregates SPI/I2C sensor readings and forwards them as ASCII or binary frames over a USART link. Its MSSP peripheral handles both SPI and I2C master transactions to digital temperature, pressure, or IMU sensors, while the USART sends data to a host controller at 9600 to 115200 baud. The 14 KB Flash accommodates simple protocol stacks (e.g. NMEA-0183 lite or proprietary Modbus), the 368-byte RAM buffers a full sensor frame, and the 22 I/O provide spare pins for status LEDs and configuration jumpers. Designers migrating to new silicon typically move to PIC16F876A-I/SO in the same 28-SOIC footprint for continuity.
推荐
Security Alarm Panel Logic Board
The PIC16F876-20/SO is used in security alarm panels to scan zone inputs, drive sirens, control keypad LEDs, and communicate with central-station modems or keypads. The 22 I/O scan up to 16 zones plus 6 status outputs, the 10-bit ADC supports analog-loop supervision, and the 256-byte EEPROM stores installer-configured zone types and account codes. Its 20 MHz CPU easily runs the debounce, supervision, and dialer state machine in real time. The 28-SOIC footprint fits inside small plastic enclosures and the ICSP header allows on-bench firmware upgrades during installation. Modern alarm panels have largely migrated to PIC16F876A-I/SO or PIC18 equivalents, but the PIC16F876-20/SO remains in service across many installed legacy systems.
推荐
推荐产品汇总
工程参考数据： PIC16F876-20/SO ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | PIC16F876A-I/SO | PIC16F876T-20/SO | PIC16F873-20/SO | PIC16F886-I/SO | PIC16F874A-I/SO |
|---|---|---|---|---|---|---|
| Package | 28-SOIC | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory (Flash) | 14 KB | 14 KB | 14 KB | 7 KB | 14 KB | 7 KB |
| RAM | 368 bytes | 368 bytes | 368 bytes | 368 bytes | 368 bytes | 192 bytes |
| Data EEPROM | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes |
| Maximum CPU Clock | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| I/O Pins | 22 | 22 | 22 | 22 | 28 | 22 |
| ADC Channels | 5 (10-bit) | 5 (10-bit, improved) | 5 (10-bit) | 5 (10-bit) | 11 (10-bit) | 8 (10-bit) |
| CCP/PWM Modules | 2 | 2 | 2 | 2 | 2 | 2 |
| Silicon Revision | Original (pre-A) | A revision | Original (pre-A) | Original (pre-A) | Newer family | A revision |
| Lifecycle Status | NRND | Active | NRND | NRND | Active | Active |
关键差异点
- Higher Flash density than PIC16F873 in the same 28-SOIC footprint （对比 PIC16F873-20/SO)
- Established mid-range PIC ecosystem and 35-instruction simplicity （对比 PIC16F874A-I/SO)
- Original silicon revision (pre-A) matches legacy device-ID 0x09A0 （对比 PIC16F876A-I/SO)
设计说明
PIC16F876-20/SO requires a decoupling capacitor of 100 nF placed as close as possible between Vdd (pin 20) and Vss (pin 19 or pin 8), with a low-ESR path to the supply. The PIC16F87X datasheet (DS30292D) recommends a bulk capacitor of 10-47 uF at the regulator output to handle Vdd inrush during ICSP programming events. When the part is in SLEEP mode, current drops to a few microamps but the brown-out and watchdog circuits still draw leakage; choose a low-Iq regulator such as MCP1700 if battery life matters.
Do not assume the PIC16F876 and PIC16F876A share the same SFR register layout. The 'A' revision moved the ADC configuration registers and added oscillator-tuning bits, so code compiled for the original silicon often reads back incorrect ADC values when run on a PIC16F876A. Always check the device-ID word (read via ICSP) at startup and conditionally remap registers, or build two firmware images keyed to the silicon revision. The original PIC16F876-20/SO silicon has device-ID 0x09A0; the PIC16F876A reports 0x0E20.
Keep the MCLR/Vpp trace short and place the ICSP header (typically a 6-pin 0.1 inch header with PGC/PGD/MCLR/Vdd/Vss) on the board edge for production programming access. The PIC16F876-20/SO in 28-SOIC has Vdd on pin 20 and Vss on pin 8 plus pin 19; both ground pins must be connected for thermal and electrical performance. The OSC1/OSC2 traces should be kept short and routed away from switching signals to prevent XTAL start-up failures, especially when using a ceramic resonator.
The 10-bit ADC on PIC16F876-20/SO is rated for an acquisition time of approximately 19.72 microseconds at 20 MHz when the A/D clock is set to Fosc/32. The recommended source impedance is below 10 kohm because higher impedance increases THD and DC error. Add a buffer op-amp (e.g. MCP6001) for high-impedance analog sources such as resistive dividers or pH probes. The ADC's Vref+ can be tied to Vdd or to an external reference on RA3 for ratiometric measurements.
合规信息
RoHS / REACH / lead-free / halogen-free status was not stated in the Verified Web Data provided; LCSC listing exists but does not explicitly enumerate compliance attributes. Microchip's general corporate policy is RoHS compliance across SOIC-package parts, but this page conservatively reports 'unknown' to avoid fabrication. AEC-Q100 is not applicable - the -20/SO is the commercial grade (0C to +70C) or industrial grade (-40C to +85C), not an automotive Q-graded variant.
