PIC16F873A-I/SO - 8-bit MCU, 7KB Flash, 20MHz, 28-SOIC | Microchip
MPN: PIC16F873A-I/SO ✓ Hoạt độngPIC16F873A-I/SO Tóm tắt
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, non-volatile program memory (Flash/ROM), volatile data memory (RAM), and a configurable set of peripheral blocks (timers, ADC, communication ports, comparators). The PIC16F873A belongs to the mid-range PIC16 family, sitting in the hierarchy 8-bit MCU -> RISC MCU -> microcontroller -> embedded computing -> semiconductor. This category is the workhorse of industrial control, appliance, automotive aftermarket, and legacy consumer electronics because it balances deterministic timing, low power, and low unit cost.
Key features include 5 channels of 10-bit Analog-to-Digital conversion, two analog comparators, three timers (Timer0, Timer1, Timer2), a synchronous serial port configurable as SPI or I2C, a USART for asynchronous serial, 10-bit PWM, in-circuit serial programming (ICSP), and self-programming support. The device operates across 2.0V to 5.5V, drawing typically < 2 mA at 5V/4MHz and < 1 uA in standby. The industrial -40C to +85C operating range suits factory-floor and outdoor enclosures.
The architecture uses a Harvard RISC core with separate program and data buses, eliminating the von Neumann fetch bottleneck. The 14-bit wide instruction word compresses arithmetic-heavy code into small Flash footprints. Hardware multiply is not present, but the deterministic instruction timing and interrupt structure make real-time control loops straightforward.
Typical applications include HVAC fan/valve controllers, washing-machine motor boards, sensor signal conditioning with on-chip ADC, low-cost inverter control loops, RS-485 Modbus slave nodes, and automotive aftermarket gauge clusters. Two analog comparators plus 5-channel ADC allow direct interface to thermistors, current shunts, and rotary encoders.
When designing with this part, budget one or two I/O pins for ICSP (PGC/PGD) and reserve the MCLR pin for a proper reset network. Watch the 22 I/O budget against your peripheral count early; if a 40-pin variant is likely needed, step up to PIC16F874A/PIC16F876A/PIC16F877A in the same family before committing layouts.
This page synthesizes distributor pricing, parametric drop-in alternatives, and application guidance not consolidated on the manufacturer product page.
Bộ thay thế dễ dàng lắp đặt cho PIC16F873A-I/SO — 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 PIC16F873A-I/SO (cùng hình factor và footprint) — khác nhau ở Package, Core Architecture, Timers, ADC, Operating Temperature.
PIC16F876A-I/SO
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC16F873A-I/SP
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC16F873A-I/ML
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16F873A-E/SS
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16F873A-E/SP
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16F873A-E/ML
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC16F873A-I/SO Tỷ lệ tối đa & tính chất điện
| Core Architecture | PIC16 8-bit RISC (Harvard) |
| Program Memory | 7 KB (4K x 14) Flash |
| RAM | 192 bytes |
| EEPROM | 128 bytes |
| Instruction Set | 35 single-word instructions |
| Maximum CPU Frequency | 20 MHz (200 ns instruction cycle) |
| Supply Voltage (VDD) | 2.0 V to 5.5 V |
| I/O Pins | 22 |
| ADC | 5 channels, 10-bit |
| Analog Comparators | 2 |
| Timers | 3 (Timer0 8-bit, Timer1 16-bit, Timer2 8-bit) |
| PWM | 10-bit resolution, 2 channels |
| Communication | SPI / I2C (SSP), USART/SCI |
| Nhiệt độ hoạt động | -40 C to +85 C (industrial) |
| Hộp | 28-pin SOIC (SO) |
| In-Circuit Programming | ICSP supported |
| Self-Programming | Yes |
| Trạng thái RoHS | Compliant |
Cấu hình chân PIC16F873A-I/SO
| Chân 1 | MCLR/VPP — Master clear (reset) input / programming voltage |
| Chân 2 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Chân 3 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Chân 4 | RA2/AN2/VREF- — PORTA bit 2 / analog input 2 / VREF- |
| Chân 5 | RA3/AN3/VREF+ — PORTA bit 3 / analog input 3 / VREF+ |
| Chân 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Chân 7 | RA5/AN4/SS — PORTA bit 5 / analog input 4 / SSP slave select |
| Chân 8 | OSC2/CLKOUT — Oscillator output / clock out |
| Chân 9 | OSC1/CLKIN — Oscillator input / clock in |
| Chân 10 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Chân 11 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / Capture-Compare-PWM 2 |
| Chân 12 | RC2/CCP1 — PORTC bit 2 / Capture-Compare-PWM 1 |
| Chân 13 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Chân 14 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Chân 15 | RC5/SDO — PORTC bit 5 / SPI data out |
| Chân 16 | RC6/TX/CK — PORTC bit 6 / USART async transmit / sync clock |
| Chân 17 | RC7/RX/DT — PORTC bit 7 / USART async receive / sync data |
| Chân 18 | VSS — Ground reference |
| Chân 19 | VDD — Positive supply voltage |
| Chân 20 | RB0/INT — PORTB bit 0 / external interrupt |
| Chân 21 | RB1 — PORTB bit 1 |
| Chân 22 | RB2 — PORTB bit 2 |
| Chân 23 | RB3/PGM — PORTB bit 3 / low-voltage programming enable |
| Chân 24 | RB4 — PORTB bit 4 |
| Chân 25 | RB5 — PORTB bit 5 |
| Chân 26 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Chân 27 | RB7/PGD — PORTB bit 7 / ICSP data |
| Chân 28 | VSS — Ground reference (second VSS pin on 28-pin variant) |
Ứng dụng tiêu biểu
PIC16F873A-I/SO phù hợp cho 7 Áp dụngs: HVAC Fan and Valve Controller, Washing Machine Motor Control Board, Industrial RS-485 Modbus Slave Node, Automotive Aftermarket Gauge Cluster, Sensor Signal Conditioning Front-End, Battery-Backed Real-Time Clock Module, Custom USB-to-UART Bridge (Firmware CDC).
HVAC Fan and Valve Controller
The PIC16F873A-I/SO drives triac-controlled AC fan motors and thermostatic zone valves in HVAC systems. Its 5-channel 10-bit ADC reads thermistor temperature sensors directly without external signal conditioning, while the two analog comparators handle zero-crossing detection for triac firing. The 20MHz CPU executes 200 ns instruction cycles, fast enough for software PWM dimming at 1 kHz update rate. The 7KB Flash fits typical HVAC state machines including PID control loops and EEPROM-backed schedule storage. Per datasheet 30262D, the 22 I/O budget accommodates 3 triac outputs, 2 relay drivers, a 4x3 keypad matrix, and the LCD data bus. Industrial -40C to +85C operation tolerates attic equipment compartments.
Được đề xuất
Washing Machine Motor Control Board
The PIC16F873A-I/SO is a classic 8-bit MCU in washing-machine motor controllers, driving triac-fired universal motors and solenoid valves. Its 10-bit PWM channels deliver smooth speed ramping, while Timer1 (16-bit) handles back-EMF zero-crossing timing for synchronous rectification. Per Microchip datasheet 30262D, the 7KB Flash accommodates drum control state machines, water-level sensing via ADC, door-lock interlocks, and fault logging. The 22 I/O pins cover the keypad, 7-segment display driver, and motor-driver enable lines. Industrial temperature grade and 5V operation suit the noisy electrical environment of an appliance back panel.
Được đề xuất
Industrial RS-485 Modbus Slave Node
The PIC16F873A-I/SO implements a Modbus-RTU slave node on RS-485 with the on-chip hardware USART. The synchronous serial port (SSP) can be reconfigured for SPI to drive a local sensor front-end or for I2C to read an external RTC. Per datasheet 30262D, the 7KB Flash fits Modbus protocol state machines, register maps, and CRC16 routines. The 192-byte RAM buffers 16-bit holding registers, and the 128-byte EEPROM stores calibration constants through power cycles. The 2.0V to 5.5V supply range accepts 24V industrial bus power via a 5V LDO. Watchdog timer plus brown-out reset ensure field-reliable operation in industrial cabinets.
Được đề xuất
Automotive Aftermarket Gauge Cluster
The PIC16F873A-I/SO powers aftermarket automotive gauges including oil-pressure, boost, and AFR displays. The 5-channel 10-bit ADC samples 0-5V sensor signals from automotive transducers, while Timer0 handles tachometer pulse-counting from ignition coils. Per datasheet 30262D, the 22 I/O drive multiplexed 7-segment or OLED displays, button inputs, and warning-LED outputs. Industrial -40C to +85C temperature operation tolerates under-dash thermal stress. The 7KB Flash accommodates gauge calibration tables and EEPROM stores user preferences. Note: this part is industrial-grade, not AEC-Q100 - use PIC16F876A-I/SO for OEM-grade automotive designs.
Được đề xuất
Sensor Signal Conditioning Front-End
The PIC16F873A-I/SO serves as a smart sensor front-end, reading bridge sensors, thermistors, and 4-20 mA transducers via its 10-bit ADC and linearizing outputs to UART, SPI, or I2C. Per datasheet 30262D, the 7KB Flash accommodates polynomial calibration routines, while the 128-byte EEPROM stores factory calibration coefficients. The two analog comparators enable window-comparator alarm outputs without CPU intervention. The 22 I/O drive status LEDs, control relays, and accept button inputs. The 5V supply and -40C to +85C range suit process-control transmitter housings.
Được đề xuất
Battery-Backed Real-Time Clock Module
The PIC16F873A-I/SO forms a standalone RTC module with battery backup, displaying time/date on an LCD and synchronizing via GPS or NTP through UART. Per datasheet 30262D, the 22 I/O drive 4-bit LCD data, RS, and enable lines plus accept GPS PPS input on CCP1 for sub-second accuracy. The 7KB Flash fits Gregorian calendar arithmetic and time-zone logic, and the 128-byte EEPROM stores user-set alarms and DST rules. The 2.0V minimum VDD allows CR2032 coin-cell operation when mains power fails. ICSP pins are reserved for in-field firmware updates via the rear-panel programming header.
Được đề xuất
Custom USB-to-UART Bridge (Firmware CDC)
With a CH340 or FTDI companion chip, the PIC16F873A-I/SO can act as a custom USB CDC device firmware-side, performing protocol translation between USB and RS-232/RS-485 for legacy industrial equipment. Per datasheet 30262D, the on-chip USART handles async serial at up to 115200 baud reliably at 20MHz, while the SSP supports SPI master to talk to a UART-over-SPI expander for additional ports. The 7KB Flash fits USB request handlers, while EEPROM stores VID/PID and serial number. This is a low-volume bridge solution when COTS USB-UART chips do not meet custom-protocol needs.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PIC16F873A-I/SO — 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 | PIC16F876A-I/SO | PIC16F873A-I/SP | PIC16F873A-I/ML | PIC16F873A-E/SS | PIC16F873A-E/SP | PIC16F873A-E/ML |
|---|---|---|---|---|---|---|---|
| Package | 28-SOIC (SO) | 28-SOIC (SO) | 28-PDIP (SP) | 28-QFN (ML) | 28-SSOP (SS) | 28-PDIP (SP) | 28-QFN (ML) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 7 KB Flash | 14 KB Flash | 7 KB Flash | 7 KB Flash | 7 KB Flash | 7 KB Flash | 7 KB Flash |
| RAM | 192 bytes | 256 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes |
| EEPROM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes |
| Maximum Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +125 C | -40 C to +125 C | -40 C to +125 C |
| Temperature Grade | Industrial (I) | Industrial (I) | Industrial (I) | Industrial (I) | Extended (E) | Extended (E) | Extended (E) |
Bảo phân biệt quan trọng
- Compact 28-pin footprint with full mid-range peripheral set (vsPIC16F876A-I/SO)
- Industrial -40C to +85C operating range (vsPIC16F873A-E/SS)
- Same die across SOIC/PDIP/QFN packages (vsPIC16F873A-I/SP)
Ghi chú thiết kế
Decouple VDD (pin 20) with 100 nF ceramic placed within 5 mm of the pin, plus a bulk 10 uF tantalum or aluminum electrolytic on the supply rail. Per Microchip datasheet 30262D, AVDD is internally tied to VDD on this 28-pin variant, so the same 100 nF cap serves both analog and digital supplies. Place the cap ground return directly to pin 18/28 VSS via a wide, short trace to avoid ground bounce corrupting ADC samples.
The MCLR pin (1) requires a 10 kohm pull-up to VDD plus a 100 nF cap to VSS for a proper power-on reset, unless internal MCLR is configured in the configuration bits. The ICSP pins RB6/PGC and RB7/PGD must be reserved for programming - do not load them with low-impedance peripherals that would interfere with the programmer. The OSC1/OSC2 pins should be guarded by a ground ring if using a high-frequency crystal to keep EMI away from the analog inputs.
Watch out for the 28-pin package losing PORT E entirely - the PIC16F873A has no RE0-RE2 pins. Designers coming from 40-pin PIC16F877A code may forget to remove PORT E references. Also, do not exceed the 25 mA sink/source per I/O pin or 200 mA per port (PORTB) total, per datasheet 30262D. Finally, when migrating to PIC16F876A, the program memory map shifts - linker scripts must be regenerated for the larger Flash.
Thông tin tuân thủ
RoHS compliant per Microchip product page. Not AEC-Q100 qualified - choose PIC16F876A-I/SO with -40 to +125 C grade or an AEC-Q100 part for OEM automotive. Halogen-free status not confirmed in verified web data.
