PIC16F84-04I/P - 4MHz 8-bit Flash MCU 1.75KB | Microchip
MPN: PIC16F84-04I/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.42 | $3.42 |
| 10 | $3.07 | $30.70 |
| 100 | $2.74 | $274.00 |
| 500 | $2.46 | $1,230.00 |
| 1,000 | $2.18 | $2,180.00 |
PIC16F84-04I/P Overview
What is a PIC microcontroller? A PIC (Peripheral Interface Controller) is a family of 8-, 16-, and 32-bit RISC-based microcontrollers originally developed by General Instrument's Microelectronics Division and continued by Microchip Technology. Within that hierarchy, PIC16F devices sit between the baseline PIC10/12/16F families and the more advanced PIC18 family, offering a balance of low cost, low power, and a 14-bit instruction word. The PIC16F84 in particular is part of the early flash-based PIC16 series that introduced in-system programmability and EEPROM data memory, a notable step up from the older EPROM PIC16Cxx parts.
Key features include 4 MHz maximum clock speed, 35 single-word instructions, 8-level hardware stack, 14-bit instruction width, 64 bytes of EEPROM data memory, an integrated power-on reset, watchdog timer with on-chip RC oscillator, and programmable code protection. The industrial temperature range (-40C to +85C) and 4.0V to 5.5V operating voltage make it broadly compatible with 5V logic systems commonly found in legacy industrial control boards.
Architecturally, the PIC16F84 uses a Harvard-style RISC core with separate program and data buses, allowing instruction fetch and data access to occur in the same cycle. Its CMOS design with nanoWatt-style low-power techniques delivers very low standby current, which is critical for battery-backed or energy-harvesting nodes. The 13 I/O pins are arranged across PORT A (5 pins) and PORT B (8 pins), with PORTB featuring internal weak pull-ups that can be enabled per-pin in software.
Typical applications include legacy industrial control modules, educational microcontroller kits, hobbyist electronics, simple sensor interfaces, timer/counter circuits, and replacements for older PIC16C5x and PIC16C71x designs. It is also widely used as a teaching reference in university embedded systems curricula because of its straightforward peripheral set and abundant example code.
When designing with this part, note that Microchip has officially recommended the PIC16F84A as a newer replacement; the two share the same 18-pin DIP pinout, but the 'A' revision adds 200 ns instruction execution and improved peripherals. For new designs, the PIC16F84A or a PIC16F1xx device is generally preferred, while the PIC16F84-04I/P remains common in long-life industrial systems and in sustaining legacy production boards.
This page synthesizes distributor pricing, drop-in alternatives (PIC16F84A-04I/P, PIC16F84-10I/P), and practical design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for PIC16F84-04I/P — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with PIC16F84-04I/P (same form factor and footprint) — differing in Timers, Instruction Set, Mounting Type, Core Architecture, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F84A-04I/P
✅ Drop-In✓ In Stock
$1.65 / Unit
View Datasheet →PIC16F84A-20/P
✅ Drop-In✓ In Stock
$1.72 / Unit
View Datasheet →PIC16F84A-20I/P
✅ Drop-In✓ In Stock
$2.43 / Unit
View Datasheet →PIC16F84-10I/P
✅ Drop-In✓ In Stock
$5.92 / Unit
View Datasheet →PIC16F84-04/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F84A-04I/P
✅ Drop-In ⚠️ 参数待验证✓ In Stock
$1.65 / Unit
View Datasheet →PIC16F84-04I/P Maximum Ratings & Electrical Characteristics
| Core Processor | PIC |
| Core Size | 8-Bit |
| Core Family | PIC16F8X |
| Instruction Set | 35 single-word instructions, 14-bit wide |
| Max Clock Speed | 4 MHz |
| Program Memory Type | FLASH |
| Program Memory Size | 1.75 KB (1K x 14) |
| RAM Size | 68 bytes |
| EEPROM Size | 64 bytes |
| Number of I/O Pins | 13 (PORTA 5 + PORTB 8) |
| Supply Voltage (Vdd) | 4.0 V to 5.5 V |
| Operating Temperature Range | -40 C to +85 C (Industrial, 'I' suffix) |
| Package / Case | 18-PDIP (Through-Hole, 0.300 inch, plastic DIP-18) |
| Mounting Type | Through-Hole |
| Data Converters | None (no on-chip ADC) |
| Oscillator Type | External RC or crystal (XT, HS, LP, RC modes) |
| Connectivity | None (no UART, I2C, or SPI peripheral) |
| Peripherals | POR (Power-on Reset), WDT (Watchdog Timer) |
| Program Memory Endurance | 1000 erase/write cycles typical (FLASH) |
| EEPROM Endurance | 1,000,000 erase/write cycles typical |
| ROM Type | Flash (per DigiChip cross reference) |
| RoHS Status | Compliant |
| Lead-Free / Halogen-Free | Lead-free (verify reel/listing for halogen-free status) |
| Recommended Replacement | PIC16F84A-04I/P (per Microchip product page) |
PIC16F84-04I/P Pin Configuration
| Pin 1 | RA2 — Digital I/O port A bit 2 |
| Pin 2 | RA3 — Digital I/O port A bit 3 |
| Pin 3 | RA4/T0CKI — Digital I/O port A bit 4 / Timer0 clock input |
| Pin 4 | MCLR — Master Clear (active-low reset) / ICSP Vpp |
| Pin 5 | Vss — Ground reference |
| Pin 6 | RB0/INT — Digital I/O port B bit 0 / External interrupt |
| Pin 7 | RB1 — Digital I/O port B bit 1 |
| Pin 8 | RB2 — Digital I/O port B bit 2 |
| Pin 9 | RB3 — Digital I/O port B bit 3 |
| Pin 10 | RB4 — Digital I/O port B bit 4 (interrupt-on-change) |
| Pin 11 | RB5 — Digital I/O port B bit 5 (interrupt-on-change) |
| Pin 12 | RB6 — Digital I/O port B bit 6 / ICSP clock |
| Pin 13 | RB7 — Digital I/O port B bit 7 / ICSP data |
| Pin 14 | Vdd — Positive supply, 4.0 V to 5.5 V |
| Pin 15 | OSC2/CLKOUT — Crystal/Resonator pin 2 / Fosc/4 output |
| Pin 16 | OSC1/CLKIN — Crystal/Resonator pin 1 / External clock input |
| Pin 17 | RA0 — Digital I/O port A bit 0 |
| Pin 18 | RA1 — Digital I/O port A bit 1 |
Typical Applications
PIC16F84-04I/P is suitable for 6 applications: Legacy Industrial Control Modules, Educational Microcontroller Kits, Hobbyist and DIY Electronics, Sensor Interface and Data Acquisition Front-Ends, Replacement of Obsolete PIC16C5x and PIC16C71x Designs, Battery-Backed Timer and Counter Modules.
Legacy Industrial Control Modules
The PIC16F84-04I/P is widely used as a sustainment part for legacy industrial control modules where the BOM and PCB layout have been frozen for many years. Its 4 MHz RISC core, 1.75 KB flash and 13 I/O pins are sufficient for relay drivers, indicator-lamp sequencers, keypad scanners, and discrete-logic replacements. Its industrial -40C to +85C rating matches factory-floor ambient requirements, and the 4.0V to 5.5V supply aligns with 5V PLC backplanes. Because many OEMs ship equipment with 15- to 20-year service warranties, this part remains in active distributor inventory even though newer PIC16F1xx devices exist.
Recommended
Educational Microcontroller Kits
Universities and embedded-systems training programs have standardized on the PIC16F84 family for decades because the 18-PDIP through-hole package is easy to breadboard, the 35-instruction RISC core is simple to teach, and there is a vast library of example code in assembler and C. The 1.75 KB flash fits introductory assignments (blink, PWM, keypad read, UART bit-bang) and the on-chip EEPROM supports small data-logging demos. The 4 MHz ceiling is high enough for instructional timing experiments without confusing students with deep clock-tree concepts.
Recommended
Hobbyist and DIY Electronics
The PIC16F84-04I/P is a staple of hobbyist designs such as LED chasers, IR remote decoders, simple motor speed controllers, and homebrew function generators. Its 13 I/O pins are enough to drive 7-segment displays with bit multiplexing and its flash memory is in-system programmable through the ICSP pins (RB6/RB7/MCLR/Vdd/Vss), so end users can re-flash the chip with a $5 PICKit without removing it from the board. Through-hole PDIP makes hand-soldering trivial on perfboard or stripboard projects.
Recommended
Sensor Interface and Data Acquisition Front-Ends
The PIC16F84-04I/P is a good fit for low-speed, on-off sensor front ends: read a few contact-closure or 0-5V digital lines, de-bounce, and forward a result to a higher-level system. The 64 bytes of on-chip EEPROM is a real differentiator, because the F84 can store calibration constants, sensor IDs, or up-time counters without external storage. While it lacks an ADC, designers often pair it with an external I2C or SPI ADC (bit-banged) when analog measurements are needed, leveraging the PIC16F84's GPIOs for control and the EEPROM for configuration data.
Recommended
Replacement of Obsolete PIC16C5x and PIC16C71x Designs
Designers tasked with sustaining production boards originally built around EPROM-based PIC16C5x and PIC16C71x microcontrollers routinely migrate to the PIC16F84-04I/P because it is the closest flash-and-EEPROM equivalent with the same 18-pin DIP outline and similar peripheral set. Compared with the EPROM parts, the F84 adds in-system re-programmability, internal oscillator options, and EEPROM data memory, all while keeping the pinout and 5V supply compatible. Migration effort is usually limited to addressing differences in the SFR map and interrupt vector layout.
Recommended
Battery-Backed Timer and Counter Modules
The PIC16F84-04I/P is well suited to dedicated timer/counter applications such as irrigation controllers, parking-meter accumulators, and simple access-control keypads. The PIC's nanoWatt-style sleep current keeps power draw negligible on battery standby, the 64-byte EEPROM retains accumulated counts across power cycles, and the watchdog timer protects against software lockups in unattended installations. PORTB's internal weak pull-ups simplify direct switch and keypad wiring without external resistors.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F84-04I/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F84A-04I/P | PIC16F84A-20/P | PIC16F84A-20I/P | PIC16F84-10I/P | PIC16F84-04/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-PDIP | 18-PDIP - same | 18-PDIP - same | 18-PDIP - same | 18-PDIP - same | 18-PDIP - same |
| Max Clock Speed | 4 MHz | 4 MHz | 20 MHz | 20 MHz | 10 MHz | 4 MHz |
| Program Memory (Flash) | 1.75 KB (1K x 14) | 1.75 KB (1K x 14) | 1.75 KB (1K x 14) | 1.75 KB (1K x 14) | 1.75 KB (1K x 14) | 1.75 KB (1K x 14) |
| RAM Size | 68 bytes | 68 bytes | 68 bytes | 68 bytes | 68 bytes | 68 bytes |
| EEPROM Size | 64 bytes | 64 bytes | 64 bytes | 64 bytes | 64 bytes | 64 bytes |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | 0 C to +70 C (Commercial) | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | 0 C to +70 C (Commercial) |
| Supply Voltage | 4.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 4.0 V to 5.5 V | 4.0 V to 5.5 V |
| Number of I/O Pins | 13 | 13 | 13 | 13 | 13 | 13 |
| Recommended Replacement | PIC16F84A-04I/P | Yes (supersedes original F84) | Yes (A-revision 20 MHz) | Yes (A-revision 20 MHz industrial) | Same generation, faster clock | Same die, commercial temp |
Key Differentiators
- Improved instruction execution and peripheral set over the original PIC16F84 (vs PIC16F84-04I/P (this part))
- 5x higher clock speed in the same package (vs PIC16F84A-04/P (20 MHz commercial grade))
- Same die family with higher clock ceiling for the same industrial temperature (vs PIC16F84A-20I/P)
Design Notes
Estimated: Vdd must be between 4.0 V and 5.5 V on the original PIC16F84; the PIC16F84A revision extends this down to 2.0 V. Decouple Vdd (pin 14) with a 100 nF ceramic capacitor placed within 5 mm of the pin and a 10 uF bulk tantalum or aluminum capacitor at the supply entry point. MCLR (pin 4) needs a 10 kohm pull-up to Vdd and, for noisy environments, a 100 nF capacitor to ground to form a low-pass filter against spurious resets. Brown-out is not built in, so an external voltage supervisor such as MCP100/MCP120 is recommended for industrial designs where the 5 V rail may sag.
Code-protection bit CP is enabled by default on erased parts. Once CP is set the flash cannot be read out, but the chip can still be re-bulk-erased during reprogramming - confirming the CP setting matches your firmware update flow before locking the device in production. PORTB internal weak pull-ups (RBPU bit) must be enabled in software via the OPTION register; do not assume floating PORTB inputs will read as logic-high without that bit set. The MCLR pin must never be left floating; a floating MCLR is the most common cause of unexplained resets in PIC16F84 designs. Configuration Word is read after Vdd stabilizes; verify CONFIG settings (CP, WDT, oscillator mode) with the ICSP programmer before code release.
Estimated: Place the crystal or resonator within 10 mm of OSC1/OSC2 (pins 16/15) and route both traces over a continuous ground plane to minimize stray capacitance. Keep digital switching traces (PORTB outputs, MCLR, oscillator) at least 3 mm away from analog-sensitive traces if the board also carries analog front-end circuitry, even though the F84 itself has no ADC - because high dV/dt on these lines can couple into adjacent analog signals. Use a single ground plane on the bottom layer and stitch vias around the ICSP header (RB6, RB7, MCLR, Vdd, Vss) so the production programmer has stable signal integrity.
ICSP uses RB6 as PGC (clock) and RB7 as PGD (data). If the application uses RB6 or RB7 as outputs driving heavy loads (relays, LEDs, MOSFET gates), place a series resistor near the PIC pin (typically 100-470 ohm) so that the in-circuit programmer does not fight with the load during programming. Pull MCLR low to enter ICSP mode via the high-voltage entry sequence; ensure MCLR can reach at least Vpp = 13 V or use the low-voltage ICSP entry mode supported by newer programmers.
Compliance Information
RoHS-compliant per Microchip product page. The 'I' suffix indicates industrial temperature grade (-40C to +85C); AEC-Q100 is not applicable for this industrial-grade (non-automotive-qualified) MCU. Halogen-free status varies by specific reel/batch - verify with Microchip for the exact lot in production. Country of origin: Thailand per GlobalSpec datasheet entry.
