PIC16F84A-04I/P - 8-bit Flash MCU, 4MHz, 1.75KB | Microchip DIP-18
부품 번호: PIC16F84A-04I/P ✓ 활성| 수량 | 단가 | 합계 |
|---|---|---|
| 1 | $2.55 | $2.55 |
| 10 | $2.31 | $23.10 |
| 100 | $2.04 | $204.00 |
| 500 | $1.82 | $910.00 |
| 1,000 | $1.65 | $1,650.00 |
PIC16F84A-04I/P 개요
A microcontroller (MCU) is a single-chip computer that integrates a CPU, non-volatile program memory (Flash/ROM), volatile data memory (RAM), and peripheral interfaces (I/O, timers, communications). Within the broader semiconductor taxonomy, an MCU sits below the microprocessor (which requires external memory) but above custom logic ICs. The PIC16F84A belongs to the PIC mid-range family of 8-bit microcontrollers, itself a subset of Microchip's 8-bit PIC portfolio alongside PIC10/12/14/16/18 families. Its position as a mid-range Flash MCU made it one of the most widely adopted learning and hobbyist controllers between the late 1990s and 2010s.
The PIC16F84A uses a Harvard architecture with separate code and data buses, a 14-bit instruction word, and two hardware I/O ports (PORTA 5-bit, PORTB 8-bit). Key features include a watchdog timer with on-chip RC oscillator, power-on reset, brown-out detection, power-saving sleep mode, in-circuit serial programming (ICSP) via RB6/RB7, and four interrupt sources. The internal RC timing chain supports selectable clock modes including external crystal/ceramic resonator and low-power LF oscillator.
Typical applications span legacy embedded control, industrial sensor conditioning, simple keypad scanners, hobbyist robotics, educational development boards, and battery-powered instruments where 1.75 KB of Flash and 13 I/O pins are sufficient. Modern designs typically migrate to PIC16F628A, PIC16F88, PIC16F1827, or PIC16F1xxx enhanced mid-range cores, but the original PIC16F84A remains in production for long-lifecycle industrial and automotive aftermarket designs.
When designing with this device, note the 4 MHz speed grade designation (-04 vs -20); at 5V the -04 grade operates up to 4 MHz and the -20 grade up to 20 MHz. Power supply decoupling requires a 100 nF ceramic capacitor close to VDD with a bulk 10-47 uF electrolytic, and MCLR must be pulled high through a 10-47 kohm resistor for normal operation.
This page synthesizes distributor pricing, drop-in 18-pin PDIP alternatives, and practical design notes not consolidated in the manufacturer datasheet alone. Engineers seeking modern feature parity should consult the PIC16F628A migration guide referenced in the design notes.
드롭인 대체품: PIC16F84A-04I/P — 동일 패키지, 핀 호환. PCB 재작업이 필요한 다른 패키지 부품은 제외됩니다.
이 시리즈의 변형
다음과 드롭인 호환되는 동일 시리즈 모델: PIC16F84A-04I/P (동일 폼 팩터 및 풋프린트) — 차이점: Package, Timers, Core Architecture, Operating Temperature Range, Instruction Set.
빠른 비교 도구 — 나란히 비교할 대체 부품을 선택하십시오:
PIC16F84A-04E/P
✅ 드롭인✓ 재고 있음
$2.2 / 개
데이터시트 보기 →PIC16F84-04I/P
✅ 드롭인✓ 재고 있음
$2.18 / 개
데이터시트 보기 →PIC16F628A-I/P
✅ 드롭인✓ 재고 있음
$1.62 / 개
데이터시트 보기 →PIC16F84A-04/P
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
PIC16F84A-20I/P
✅ 드롭인✓ 재고 있음
$2.43 / 개
데이터시트 보기 →PIC16F84A-04I/P 최대 정격 & 전기적 특성
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Instruction Set Width | 14-bit |
| Number of Instructions | 35 single-word |
| 최대 클록 주파수 | 4 MHz (-04 speed grade) |
| Instruction Execution Time | 200 ns at 4 MHz |
| Program Memory (Flash) | 1.75 KB (1024 x 14 words) |
| RAM | 68 bytes |
| EEPROM Data Memory | 64 bytes |
| I/O Pins | 13 (PORTA 5-bit, PORTB 8-bit) |
| Timers | 1 x 8-bit Timer0 with watchdog |
| Interrupts | 4 sources |
| Operating Voltage | 4.0 V to 5.5 V |
| 동작 온도 | -40C to +85C (Industrial) |
| 패키지 | 18-pin PDIP (P) |
| 실장 유형 | Through-Hole |
| ICSP Programming | Yes (RB6/RB7) |
| Brown-Out Reset | Yes |
| Power-On Reset | Yes |
| Lead-Free | Yes (per Microchip product page) |
PIC16F84A-04I/P 핀 구성
| 핀 1 | RA2 — PORTA bit 2 (bidirectional I/O) |
| 핀 2 | RA3 — PORTA bit 3 (bidirectional I/O) |
| 핀 3 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input (open-drain) |
| 핀 4 | MCLR/VPP — Master Clear (reset, active low) / programming voltage input |
| 핀 5 | VSS — Ground reference |
| 핀 6 | RB0/INT — PORTB bit 0 / external interrupt input |
| 핀 7 | RB1 — PORTB bit 1 (bidirectional I/O) |
| 핀 8 | RB2 — PORTB bit 2 (bidirectional I/O) |
| 핀 9 | RB3 — PORTB bit 3 (bidirectional I/O) |
| 핀 10 | RB4 — PORTB bit 4 (bidirectional I/O, interrupt-on-change) |
| 핀 11 | RB5 — PORTB bit 5 (bidirectional I/O, interrupt-on-change) |
| 핀 12 | RB6 — PORTB bit 6 (bidirectional I/O, interrupt-on-change, ICSP clock) |
| 핀 13 | RB7 — PORTB bit 7 (bidirectional I/O, interrupt-on-change, ICSP data) |
| 핀 14 | VDD — Positive supply voltage (4.0V to 5.5V) |
| 핀 15 | OSC2/CLKOUT — Oscillator crystal output / clock output (Fosc/4) |
| 핀 16 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| 핀 17 | RA0 — PORTA bit 0 (bidirectional I/O) |
| 핀 18 | RA1 — PORTA bit 1 (bidirectional I/O) |
일반적인 애플리케이션
PIC16F84A-04I/P 적합 용도: 6 애플리케이션s: Educational Microcontroller Development Boards, Industrial Sensor Conditioning and Control, Automotive Aftermarket and Accessory Modules, Battery-Powered Instruments and Remote Sensors, Hobby Robotics and Animatronics, Keypad and Simple HMI Interfaces.
Educational Microcontroller Development Boards
The PIC16F84A-04I/P is the de facto teaching platform for 8-bit microcontroller fundamentals, used in university courses, hobbyist kits, and online tutorials because of its simple 35-instruction RISC core and accessible 18-pin PDIP through-hole footprint. The 1.75 KB Flash comfortably holds introductory programs (LED blink, ADC-free analog sensing via RC time, UART bit-bang, I2C bit-bang), while 68 bytes RAM is sufficient for small state machines. The 4 MHz speed grade matches the popular PICkit 2/3 programmer default clock and the breadboard-friendly 5V supply rail typical of classroom labs. Industrial temperature rating (-40C to +85C) protects against accidental lab mishandling. Companion MPNs: PIC16F628A-I/P (more Flash for advanced exercises), PICkit 3 (programmer), MPLAB XC8 compiler (IDE/toolchain).
추천
Industrial Sensor Conditioning and Control
The PIC16F84A-04I/P serves legacy industrial control loops where its 13 digital I/O pins read limit switches, drive relay coils, and bit-bang simple protocols to sensors lacking native serial interfaces. The 64-byte EEPROM stores calibration constants that survive power cycling, critical for setpoint-adjustable controllers in HVAC, motor starters, and process interlocks. Brown-out reset prevents undefined behavior during supply brown-outs common on industrial 24V rails, while the watchdog timer recovers the MCU from software lockups in unattended installations. The 4 MHz instruction cycle (200 ns) is sufficient for slow polling loops at 10-100 Hz without burdening the CPU. Companion MPNs: ULN2003A (relay driver), 4N25 (optoisolator), LM358 (signal conditioning op-amp).
추천
Automotive Aftermarket and Accessory Modules
The PIC16F84A-04I/P powers long-lifecycle automotive aftermarket accessories such as alarm systems, remote-entry controllers, LED lighting sequencers, and gauge drivers because the part remains in active production with stable pinout and documentation. Its 13 I/O pins directly drive automotive relays, LEDs, and piezo buzzers through simple BJT/MOSFET drivers without external logic. The EEPROM stores user-configurable settings (alarm codes, lighting preferences) that survive battery disconnects, and the watchdog timer ensures recovery from automotive electrical noise spikes. The 4 MHz clock is sufficient for slow polling tasks like remote-control decoding at 1-10 kHz carrier frequencies. Industrial temperature rating covers under-dash environments. Companion MPNs: TJA1050 (CAN interface for modern migration), LM7805 (5V regulator).
추천
Battery-Powered Instruments and Remote Sensors
The PIC16F84A-04I/P supports battery-powered measurement instruments like handheld multimeter accessories, environmental data loggers, and remote weather stations where its 1.75 KB Flash holds compact measurement routines and 64-byte EEPROM accumulates timestamped readings. The sleep mode with watchdog wakeup achieves microamp quiescent current, extending battery life to months or years in low-duty-cycle applications. Brown-out reset prevents data corruption when batteries deplete below the 4.0V minimum, protecting the EEPROM from undefined writes. The 13 I/O pins interface to I2C temperature/humidity sensors via bit-banged routines, eliminating the need for an external peripheral IC. Companion MPNs: DS18B20 (1-Wire temperature sensor), HT7333 (3.3V LDO for battery regulation).
추천
Hobby Robotics and Animatronics
The PIC16F84A-04I/P drives hobby robotics projects, animatronic puppets, and small servo controllers where its 13 I/O pins directly control 4-8 servos via bit-banged PWM (50 Hz frame, 1-2 ms pulse width). The 4 MHz clock generates 200 ns resolution pulse timing, accurate enough for hobby-grade servo positioning, and 68 bytes RAM holds up to 8 simultaneous servo positions. ICSP programming allows in-circuit firmware updates without disassembling the robot, and the 18-pin PDIP through-hole package is robust against vibration in wheeled robots. EEPROM stores motion sequence presets that survive power cycling. Companion MPNs: SG90 micro servo, HC-SR04 ultrasonic sensor, L293D motor driver.
추천
Keypad and Simple HMI Interfaces
The PIC16F84A-04I/P scans 4x4 or smaller matrix keypads and drives 7-segment or character LCD displays in access-control panels, security keypads, and simple human-machine interfaces. Its 13 I/O pins handle an 8-wire keypad matrix (4 rows + 4 columns) plus 4-5 display control lines, while internal pull-ups on PORTB eliminate external resistors for the keypad rows. The 1.75 KB Flash stores lookup tables for hex-to-7-segment decoding, password validation, and debounce state machines, and the 64-byte EEPROM retains access credentials and audit trail counters across power cycles. The 4 MHz instruction cycle executes the keypad scan and display refresh loops within 10 ms latency, imperceptible to users. Companion MPNs: HD44780 16x2 LCD, MM74C922 keypad encoder (for larger matrices).
추천
추천 제품 요약
엔지니어링 참조 데이터: PIC16F84A-04I/P — 비교, 설계 지침 및 규정 준수 정보.
선택 가이드
대체품과의 비교
| 파라미터 | 이 제품 | PIC16F84A-04E/P | PIC16F84-04I/P | PIC16F628A-I/P | PIC16F84A-04/P | PIC16F84A-20I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-pin PDIP | 18-pin PDIP - same | 18-pin PDIP - same | 18-pin PDIP - same | 18-pin PDIP - same | 18-pin PDIP - same |
| Max Clock Frequency | 4 MHz | 4 MHz | 4 MHz | 20 MHz | 4 MHz | 20 MHz |
| Flash Program Memory | 1.75 KB (1024 x 14) | 1.75 KB | 1.75 KB | 3.5 KB (2x larger) | 1.75 KB | 1.75 KB |
| RAM | 68 bytes | 68 bytes | 68 bytes | 224 bytes (3.3x larger) | 68 bytes | 68 bytes |
| EEPROM | 64 bytes | 64 bytes | 64 bytes | 128 bytes (2x larger) | 64 bytes | 64 bytes |
| I/O Pins | 13 | 13 | 13 | 16 | 13 | 13 |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) |
| Internal Oscillator | No (external required) | No | No | Yes (4 MHz internal) | No | No |
| USART Module | No (bit-bang required) | No | No | Yes (hardware USART) | No | No |
주요 차별점
- Industrial temperature grade for harsh environments (vs PIC16F84A-04/P)
- 4 MHz speed grade matches standard educational kits (vs PIC16F84A-20I/P)
- Harvard architecture with 14-bit instruction word (vs PIC16F628A-I/P)
설계 노트
The PIC16F84A-04I/P requires a stable 4.0V to 5.5V supply on pin 14 (VDD) with pin 5 (VSS) tied to ground. Place a 100 nF ceramic decoupling capacitor within 5 mm of the VDD pin to suppress high-frequency noise from the internal clock edges; add a bulk 10 uF electrolytic on the same rail if the supply traces exceed 50 mm or share with relay coils. The MCLR pin (pin 4) must be pulled high through a 10-47 kohm resistor for normal operation; leaving MCLR floating causes intermittent resets. Brown-out reset is enabled by the configuration bit and triggers at approximately 4.0V; verify that downstream circuits tolerate the reset assertion time.
Three pitfalls are common when designing with the PIC16F84A: (1) confusing the -04 speed grade (4 MHz max) with the -20 grade (20 MHz max) - they share the same die but different oscillator range; (2) ignoring the OPTION_REG pull-up disable bit on PORTB, which can cause unintended interrupts on RB4-RB7 interrupt-on-change pins if external pull-ups are absent; (3) assuming ICSP works without isolating the MCLR pull-up from VPP - the PICkit programmer drives VPP to about 13V during programming, which back-feeds through weak pull-ups and may latch-up the MCLR circuit. Use a diode or current-limiting resistor to isolate MCLR from external reset circuits.
For reliable oscillator operation, place the crystal or ceramic resonator within 10 mm of pins 15 (OSC2) and 16 (OSC1) and route the OSC traces with short, symmetrical paths. Avoid routing high-frequency digital signals (PORTB edges, relay drive lines) directly above or below the oscillator traces; capacitive coupling modulates the load capacitance and shifts the oscillator frequency by 1-3 percent, causing UART bit-rate errors and timer drift. Add a ground guard ring around the oscillator components if the PCB has dense digital routing nearby. For sleep-mode designs, the watchdog timer uses an internal 31 kHz RC oscillator that drifts with temperature and supply voltage.
규정 준수 정보
RoHS and lead-free per Microchip product page. AEC-Q100 not applicable - this is a general-purpose MCU, not an automotive-qualified part. For AEC-Q100 qualified PIC microcontrollers in automotive designs, choose the PIC16F84A-04I/PSLG (automotive PPAP) or migrate to PIC16F1827-I/P.
