PIC16F84A-04E/SS - 8-bit 4MHz 1.75KB Flash MCU | Microchip
MPN: PIC16F84A-04E/SS ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.5 | $7.50 |
| 10 | $6.75 | $67.50 |
| 100 | $6.05 | $605.00 |
| 500 | $5.45 | $2,725.00 |
| 1,000 | $4.85 | $4,850.00 |
PIC16F84A-04E/SS Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program and data memory, I/O peripherals, and timers onto one IC. Within the broader taxonomy, the PIC16F84A belongs to the 8-bit MCU class, which sits below 32-bit Cortex-M microcontrollers in compute power but excels at deterministic real-time control, low power consumption, and ease of use. Its 35 single-word RISC instruction set simplifies code development and verification, making it popular for embedded learning and legacy industrial designs.
Key features of the PIC16F84A-04E/SS include a 4 MHz maximum clock rate (the -04 speed grade), 1024 words of Flash program memory (1K x 14), 68 bytes of general-purpose SRAM, 64 bytes of data EEPROM, and a wide 2.0 V to 5.5 V operating voltage range. The 13 I/O pins each support independent direction control, while the on-chip peripherals cover the essentials needed for standalone control without external glue logic. The -04E temperature grade extends the operating range to -40C to +125C.
Architecturally, the PIC16F84A uses Microchip's Harvard RISC core with separate program and data buses, which enables single-cycle instruction fetch and a deterministic 4-clock instruction cycle at 4 MHz. The 14-bit instruction word packs more opcode space than 8-bit cores, supporting bit-oriented operations, literal arithmetic, and direct/indirect addressing in a single cycle. The integrated EEPROM endurance is rated at 1M erase/write cycles with 40-year data retention, and Flash program memory endurance reaches 1000 erase/write cycles.
Typical applications include hobby and educational microcontroller platforms, simple sensor and actuator controllers, automotive interior modules, industrial timing and control subsystems, low-end consumer appliance controllers, and legacy equipment retrofits. The 20-SSOP footprint allows compact board placement where a 18-pin DIP variant cannot fit, while preserving pinout compatibility with the PIC16F84A series.
When designing with this part, mind the difference between the -04 (4 MHz) and -10 (10 MHz) speed grades, and note the supply-current increase at higher clock rates. Ensure decoupling capacitors are placed within 5 mm of VDD, and confirm the in-circuit serial programming (ICSP) connections (RB6, RB7, MCLR) are accessible during production for firmware load. According to Microchip documentation, the device is part of the mature PIC16F84A family, with newer 16F1xxx mid-range parts offering upgraded peripherals for new designs.
This page synthesizes distributor pricing, drop-in alternative cross-references, and practical design notes that complement the manufacturer datasheet. Engineers evaluating this part for new designs should weigh the PIC16F84A's simplicity and code stability against newer PIC16F1xxx alternatives that offer more peripherals at comparable cost.
Drop-in alternatives for PIC16F84A-04E/SS — 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 PIC16F84A-04E/SS (same form factor and footprint) — differing in Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F84A-04I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F84A-04/SS
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC16F84A-04E/SS Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Core Size | 8-Bit |
| Maximum Clock Speed | 4 MHz |
| Instruction Cycle Time | 200 ns (at 4 MHz) |
| Program Memory Type | FLASH |
| Program Memory Size | 1.75 KB (1K x 14) |
| Data RAM | 68 bytes |
| Data EEPROM | 64 bytes |
| Number of I/O Pins | 13 |
| Operating Voltage Range | 2.0 V to 5.5 V |
| Operating Temperature Range | -40C to +125C (Extended -E grade) |
| Peripherals | POR, WDT |
| Connectivity | None (no UART/SPI/I2C on this device) |
| Instruction Set | 35 single-word instructions |
| Package Type | 20-SSOP (5.30 mm body, 0.65 mm pitch) |
| Mounting Type | Surface Mount |
PIC16F84A-04E/SS Pin Configuration
| Pin 1 | RA5/MCLR/VPP — I/O / Master Clear Reset / Programming voltage input |
| Pin 2 | RA0/AN0 — I/O / Analog input (on PIC16F88; digital-only on PIC16F84A) |
| Pin 3 | RA1/AN1 — I/O / Analog input (on PIC16F88; digital-only on PIC16F84A) |
| Pin 4 | RA2/AN2 — I/O / Analog input (on PIC16F88; digital-only on PIC16F84A) |
| Pin 5 | RA3/AN3 — I/O / Analog input (on PIC16F88; digital-only on PIC16F84A) |
| Pin 6 | RA4/RTCC — I/O / Timer0 clock input (open-drain output) |
| Pin 7 | RA6 — I/O (alternate function on PIC16F84A; OSC2 on PIC16F84) |
| Pin 8 | RA7 — I/O (alternate function on PIC16F84A; OSC1 on PIC16F84) |
| Pin 9 | VSS — Ground reference |
| Pin 10 | VDD — Positive supply voltage |
| Pin 11 | RB0/INT — I/O / External interrupt input |
| Pin 12 | RB1 — I/O |
| Pin 13 | RB2 — I/O |
| Pin 14 | RB3 — I/O |
| Pin 15 | RB4 — I/O (interrupt-on-change) |
| Pin 16 | RB5 — I/O (interrupt-on-change) |
| Pin 17 | RB6 — I/O (interrupt-on-change) / ICSP clock |
| Pin 18 | RB7 — I/O (interrupt-on-change) / ICSP data |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply voltage |
Typical Applications
PIC16F84A-04E/SS is suitable for 6 applications: Hobby and Educational Microcontroller Platforms, Industrial Timing and Control Subsystems, Simple Sensor and Actuator Controllers, Automotive Interior Modules (Legacy), Low-End Consumer Appliance Controllers, Legacy Equipment Retrofit and Repair.
Hobby and Educational Microcontroller Platforms
The PIC16F84A-04E/SS is widely used in university coursework and hobbyist learning kits because its 35-instruction RISC set, 1.75 KB Flash, and 13 I/O pins give students a manageable platform to learn embedded C and assembly. Its 4 MHz clock provides deterministic timing sufficient to demonstrate control loops, timers, and I/O toggling. Source: Microchip PIC16F84A datasheet. The 20-SSOP variant is suited for surface-mount teaching boards where through-hole DIP would clutter the layout. For breadboard prototyping, the DIP PIC16F84A-04E/P version is preferred; the SSOP shares identical peripheral behavior so firmware ports seamlessly. This pairing allows instructors to teach a single firmware codebase across both packages.
Recommended
Industrial Timing and Control Subsystems
The PIC16F84A-04E/SS fits legacy industrial control boards where deterministic real-time response, watchdog timer supervision, and 125C Extended-temperature operation are mandatory. Its 4 MHz clock drives software-timed state machines for conveyor sequencers, relay drivers, and machine interlocks without an RTOS overhead. The 13 I/O pins map directly to optocoupler-isolated input banks and TRIAC outputs. Designers should note that newer PIC16F1xxx parts offer enhanced peripherals, but the PIC16F84A-04E/SS remains supported in installed industrial equipment. Source: Microchip datasheet 35007b. Decoupling within 5 mm of VDD and MCLR pull-up discipline remain critical for industrial EMI immunity.
Recommended
Simple Sensor and Actuator Controllers
For sensor-reading and actuator-driving nodes that do not require UART or wireless connectivity, the PIC16F84A-04E/SS offers a minimal-bom solution: 13 I/O pins read thermistor dividers, drive MOSFET gates, and bit-bang simple protocols. Its 68-byte RAM and 1.75 KB Flash are adequate for polling loops, threshold detection, and EEPROM-backed calibration storage. The 64-byte EEPROM with 1M-cycle endurance suits applications logging setpoints across power cycles. Source: Microchip datasheet. Pin assignments should reserve RB0 for INT-driven external interrupts when sensor events must wake the core; pins RB6/RB7 must remain accessible for ICSP programming during production.
Recommended
Automotive Interior Modules (Legacy)
The PIC16F84A-04E/SS -E temperature grade handles -40C to +125C, covering passenger-compartment automotive environments for interior lighting controllers, simple gauge drivers, and accessory timers. Its 13 I/O pins can switch LED arrays and read panel buttons via matrix scanning. Source: Microchip datasheet. For new automotive designs, Microchip recommends migrating to PIC16F1xxx with CAN/LIN peripherals, but legacy service replacements remain available. Watchdog timer must be enabled for automotive EMI robustness, and the MCLR reset circuit requires a 10 kohm pull-up plus 0.1 uF decoupling. Automotive PCB layouts should keep the SSOP device away from high-dV/dt switching nodes.
Recommended
Low-End Consumer Appliance Controllers
In low-end consumer appliances such as simple coffee makers, fan controllers, and kitchen timers, the PIC16F84A-04E/SS provides the minimum functionality required: Flash for one-time-programmed behaviors, EEPROM for user-set preferences, and 13 I/O pins for keypad input, LED indicators, and TRIAC gate control. Its 2.0 V to 5.5 V supply range accommodates 3.3 V and 5 V designs without level shifters. Source: Microchip datasheet. The 1K x 14 program memory is sufficient for lookup-table-based waveform generation and timing routines. For cost-sensitive designs, Microchip offers pin-compatible newer PIC16F1xxx parts at lower unit price.
Recommended
Legacy Equipment Retrofit and Repair
The PIC16F84A-04E/SS is the canonical service part for installed equipment using the PIC16F84A in 20-SSOP. Field-replacement scenarios require pin-compatible parts to avoid PCB rework. The PIC16F84A-04I/SS, PIC16F84A-04/SS, and PIC16F84-04I/SO all share the same SSOP footprint and pinout, allowing direct board-level swap. Source: Microchip datasheet 35007b and migration document 30072b. For full code portability, designers should follow Microchip's PIC16F84 to PIC16F84A migration guide to handle SFR differences. As of 2026-09-21 the PIC16F84A is reported Obsolete, so service inventory planning should secure lifetime-buy quantities.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F84A-04E/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F84A-04I/SS | PIC16F84A-04/SS |
|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 20-SSOP | 20-SSOP | 20-SSOP |
| Maximum Clock Speed | 4 MHz | 4 MHz | 4 MHz |
| Program Memory | 1.75 KB Flash | 1.75 KB Flash | 1.75 KB Flash |
| Data RAM | 68 bytes | 68 bytes | 68 bytes |
| EEPROM | 64 bytes | 64 bytes | 64 bytes |
| I/O Pins | 13 | 13 | 13 |
| Temperature Grade | Extended -40C to +125C | Industrial -40C to +85C | Commercial 0C to +70C |
Key Differentiators
- Extended -E temperature grade for harsh environments (vs PIC16F84A-04I/SS)
- Mature 35-instruction RISC core for code stability (vs PIC16F628A-I/SS)
- Surface-mount 20-SSOP footprint for compact designs (vs PIC16F84A-04E/P)
Design Notes
Estimated: at VDD=5 V, 4 MHz, all I/O floating, the PIC16F84A-04E/SS typically draws around 2-4 mA active supply current. Place a 100 nF decoupling capacitor within 5 mm of each VDD pin (pins 10 and 20), and add a bulk 10 uF tantalum at the board entry point. For battery-powered designs, switch to PIC16F88 or PIC16F628A with sleep-mode currents below 1 uA.
MCLR must have a 10 kohm pull-up to VDD; floating MCLR causes intermittent resets. RB6 and RB7 are required for ICSP in-circuit serial programming - keep these pins accessible during production and do not strap them to ground or VDD through low impedance. Configuration bits must be programmed correctly: oscillator selection (HS vs XT vs LP) and watchdog timer enable affect startup and reset behavior. Source: Microchip PIC16F84A datasheet 35007b.
Route the 4 MHz crystal traces as short as possible, with the load capacitors (typically 15-33 pF) placed within 2 mm of the OSC1/OSC2 pins. Keep RA4 open-drain output in mind when interfacing to 5 V logic - a pull-up resistor is required. For noisy industrial environments, place a 100 ohm ferrite bead in series with VDD near the IC. Source: Microchip datasheet and application note AN588.
Compliance Information
RoHS compliance inferred from Microchip product family compliance statement; specific lead-free and halogen-free status for PIC16F84A-04E/SS not stated in the verified web data and marked as unknown. AEC-Q100 not qualified - this part targets industrial and commercial embedded use rather than automotive safety-critical applications.
