PIC16LF84A-04/P - 4MHz 1.75KB Flash 8-bit MCU | Microchip
MPN: PIC16LF84A-04/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.78 | $5.78 |
| 10 | $5.2 | $52.00 |
| 100 | $4.62 | $462.00 |
| 500 | $4.05 | $2,025.00 |
| 1,000 | $3.65 | $3,650.00 |
PIC16LF84A-04/P Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, memory, and peripherals into one silicon die. The PIC16F family uses Microchip's enhanced mid-range RISC architecture, executing one instruction per instruction cycle (200 ns at 4 MHz) from a 14-bit-wide instruction word. Hierarchy: 8-bit MCU -> microcontroller -> embedded processor -> semiconductor IC.
Key features include 13 general-purpose digital I/O pins, a 10-bit interrupt-driven ADC-free design (no on-chip ADC), hardware USART support, and an 8-bit timer/counter with a programmable prescaler. The device offers 35 single-word instructions, 8-level hardware stack, and in-circuit serial programming (ICSP) via two pins. Power-on reset, brown-out detect, and a watchdog timer with on-chip RC oscillator improve field reliability.
Architecturally, the PIC16LF84A uses Harvard bus architecture with separate program and data paths, allowing instruction fetch and data access to occur in the same cycle. The LF silicon supports full-speed operation down to 2.0V, which is critical for 2xAA battery systems. Per Microchip documentation, code written for the original PIC16F84A is binary-compatible with the LF84A, simplifying legacy code migration.
Typical applications include battery-powered sensor nodes, hobby/educational platforms (the PIC16F84 lineage is a foundational teaching device), simple motor-control logic, low-speed UART bridges, EEPROM-backed parameter storage nodes, and replacement of legacy PIC16F84A designs in industrial equipment. The 13 I/O easily drive LEDs, relays, and small character LCDs.
When designing with this part, ensure your supply stays above 2.0V at all load transients to avoid brown-out reset; add a 0.1 uF decoupling capacitor close to VDD with a bulk 10 uF electrolytic on the power rail. Note that the PIC16LF84A has NO on-chip ADC - external ADC is required for analog sensing.
This page synthesizes distributor pricing, drop-in PIC16 family alternatives, and practical design notes not found in the standalone manufacturer datasheet, helping engineers select the correct pin-compatible replacement or migration path for legacy 16F84 designs.
Drop-in alternatives for PIC16LF84A-04/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 PIC16LF84A-04/P (same form factor and footprint) — differing in Package, Operating Temperature, Core Architecture, Peripherals, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F84A-04/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF84A-04I/P
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC16F84-04/P
✅ Drop-In✓ In Stock
$3.95 / Unit
View Datasheet →PIC16LF84A-04/SO
✅ Drop-In✓ In Stock
$1.95 / Unit
View Datasheet →PIC16LF84A-04/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 Enhanced Mid-Range 8-bit RISC |
| Instruction Set Width | 14-bit |
| Maximum CPU Frequency | 4 MHz |
| Instruction Execution Time | 200 ns at 4 MHz |
| Program Memory (Flash) | 1.75 KB (1K x 14) |
| Data RAM | 68 bytes |
| Data EEPROM | 64 bytes |
| I/O Pins | 13 |
| Operating Voltage (VDD) | 2.0 V to 5.5 V |
| Operating Temperature | -40 C to +85 C (industrial) |
| Package | 18-pin PDIP (0.300 inch, 7.62 mm) |
| Mounting Type | Through-Hole |
| Timers | 1 x 8-bit Timer0 with prescaler |
| Hardware Stack | 8 levels |
| Watchdog Timer | Yes (with dedicated on-chip RC oscillator) |
| Brown-Out Reset | Yes |
| In-Circuit Serial Programming (ICSP) | Yes (2-wire) |
| Peripherals | USART, EEPROM, WDT, POR, BOR |
| RoHS Status | Compliant |
| MSL Level | 1 (unlimited floor life) |
PIC16LF84A-04/P Pin Configuration
| Pin 1 | RA2 — Bidirectional I/O pin, Port A bit 2 |
| Pin 2 | RA3 — Bidirectional I/O pin, Port A bit 3 |
| Pin 3 | RA4/T0CKI — Bidirectional I/O pin / Timer0 clock input, Port A bit 4 (open-drain output) |
| Pin 4 | MCLR — Master Clear (Reset) input, active low |
| Pin 5 | VSS — Ground reference |
| Pin 6 | RB0/INT — Bidirectional I/O pin / External interrupt input, Port B bit 0 |
| Pin 7 | RB1 — Bidirectional I/O pin, Port B bit 1 |
| Pin 8 | RB2 — Bidirectional I/O pin, Port B bit 2 |
| Pin 9 | RB3 — Bidirectional I/O pin, Port B bit 3 |
| Pin 10 | RB4 — Bidirectional I/O pin / interrupt-on-change, Port B bit 4 |
| Pin 11 | RB5 — Bidirectional I/O pin / interrupt-on-change, Port B bit 5 |
| Pin 12 | RB6/PGC — Bidirectional I/O pin / ICSP clock, Port B bit 6 |
| Pin 13 | RB7/PGD — Bidirectional I/O pin / ICSP data, Port B bit 7 |
| Pin 14 | VDD — Positive supply voltage (2.0V to 5.5V) |
| Pin 15 | OSC2/CLKOUT — Oscillator output / clock output Fosc/4 |
| Pin 16 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 17 | RA0 — Bidirectional I/O pin, Port A bit 0 |
| Pin 18 | RA1 — Bidirectional I/O pin, Port A bit 1 |
Typical Applications
PIC16LF84A-04/P is suitable for 6 applications: Battery-Powered Sensor Node, Hobby and Educational Platform, Simple Motor Control Logic, Low-Speed UART Communication Bridge, EEPROM Parameter Storage Module, Legacy PIC16F84A Replacement.
Battery-Powered Sensor Node
The PIC16LF84A-04/P's 2.0V-5.5V operating range makes it ideal for 2xAA battery-powered wireless sensor nodes and remote telemetry units. The LF silicon variant draws only a few hundred microamps at 4 MHz, enabling multi-year battery life when combined with sleep-mode duty cycling. Its 13 digital I/O pins easily interface with SPI sensors like the MCP3002 ADC, while 1.75 KB of Flash accommodates modest application logic and protocol stacks. Engineers typically pair it with an RFM69 or LoRa transceiver for sub-GHz wireless telemetry.
Recommended
Hobby and Educational Platform
The PIC16LF84A-04/P is a foundational teaching device in microcontroller education due to its simple 35-instruction RISC architecture and forgiving 18-pin PDIP package that fits standard breadboards. Educational labs use it for digital I/O, timer, and USART exercises because students can hand-solder the through-hole PDIP and debug with inexpensive PICkit programmers. The 1.75 KB Flash holds small student projects, and the wide 2.0V-5.5V supply range allows 3.3V or 5V lab power supplies to drive the part directly.
Recommended
Simple Motor Control Logic
The PIC16LF84A-04/P is widely deployed in low-cost brushed-DC motor control, stepper sequencing, and relay-driver logic where its 13 GPIO and USART suffice. The 8-bit Timer0 with programmable prescaler provides the PWM period base for software-generated PWM at modest motor frequencies. Its 4 MHz clock is fast enough for stepper pulse trains up to a few kHz while leaving sufficient instruction bandwidth for commutation logic. The LF variant's 2.0V-5.5V range supports 2xAA motor-driver boards and 3.3V logic-level interfaces.
Recommended
Low-Speed UART Communication Bridge
The PIC16LF84A-04/P's hardware USART module enables low-cost protocol bridges between RS-232, RS-485, and TTL-level UART domains at speeds up to 19.2 kbps in typical applications. The MCU's small footprint and 2.0V-5.5V VDD simplify integration into mixed-voltage industrial gateways. Field engineers use it for legacy serial-port replacements, simple MODBUS RTU nodes, and protocol-converter cards where a full PIC16F1xxx device is over-specified.
Recommended
EEPROM Parameter Storage Module
The PIC16LF84A-04/P integrates 64 bytes of on-chip EEPROM, eliminating external EEPROM ICs in many parameter-storage designs. Calibration data, serial numbers, and user settings persist across power cycles without external components. Industrial PLCs, configurable sensors, and point-of-sale terminals historically use this MCU for that reason. The 1000-cycle typical write endurance of the EEPROM suffices for infrequently-updated calibration values, and ICSP allows in-field firmware updates without desoldering.
Recommended
Legacy PIC16F84A Replacement
The PIC16LF84A-04/P serves as the modern low-voltage drop-in replacement for the legacy PIC16F84A-04/P used in industrial equipment still in field service decades after deployment. Manufacturing lines, medical instruments, and building-automation controllers originally designed around the F84A benefit from the LF84A's wider 2.0V-5.5V supply range and improved EEPROM write endurance while preserving binary-compatible code. Microchip's DS30072B migration document confirms pin and code compatibility for production replacement.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LF84A-04/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F84A-04/P | PIC16LF84A-04I/P | PIC16F84-04/P | PIC16LF84A-04/SO |
|---|---|---|---|---|---|
| Package | 18-pin PDIP (0.300 in) | 18-pin PDIP (0.300 in) - same | 18-pin PDIP (0.300 in) - same | 18-pin PDIP (0.300 in) - same | 18-pin SOIC - different (SMT) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Operating Voltage (VDD) | 2.0 V to 5.5 V | 4.5 V to 5.5 V | 2.0 V to 5.5 V | 4.5 V to 5.5 V | 2.0 V to 5.5 V |
| Maximum CPU Frequency | 4 MHz | 4 MHz | 4 MHz | 4 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 KB (512 x 14) | 1.75 KB (1K x 14) |
| Data RAM | 68 bytes | 68 bytes | 68 bytes | 68 bytes | 68 bytes |
| Data EEPROM | 64 bytes | 64 bytes | 64 bytes | 64 bytes | 64 bytes |
| I/O Pins | 13 | 13 | 13 | 13 | 13 |
| EEPROM Write Endurance | 1000 cycles typical | 1000 cycles typical | 1000 cycles typical | 100 cycles typical | 1000 cycles typical |
| Mounting Type | Through-Hole (PDIP) | Through-Hole (PDIP) | Through-Hole (PDIP) | Through-Hole (PDIP) | Surface-Mount (SOIC) |
Key Differentiators
- Low-voltage 2.0V-5.5V VDD operation across full 4 MHz (vs PIC16F84A-04/P)
- 1.75 KB Flash vs 1 KB on legacy PIC16F84 (vs PIC16F84-04/P)
- Same 18-pin PDIP footprint as the legacy F84A (vs PIC16F628A-I/P)
Design Notes
Estimated: the PIC16LF84A-04/P draws roughly 1-2 mA active at 4 MHz / 3.3V per typical datasheet figures. Place a 0.1 uF ceramic decoupling capacitor within 5 mm of the VDD pin (pin 14), plus a bulk 10 uF electrolytic on the 3.3V or 5V rail. Add a 10 kohm pull-up on MCLR (pin 4) so the device powers up cleanly. For battery designs, drive MCLR from an open-drain supervisor rather than a logic line so that brown-out resets behave correctly.
Oscillator layout is critical for reliable PIC16LF84A-04/P operation. Keep OSC1 (pin 16) and OSC2 (pin 15) traces short and symmetric, with the crystal or resonator within 10 mm of the pins. Add 22-33 pF load capacitors (per crystal datasheet) from each oscillator pin to VSS. Avoid running digital I/O traces directly beneath the oscillator traces to prevent coupling noise into the clock. For 4 MHz ceramic resonators with internal caps, the external caps can be omitted per resonator datasheet.
The PIC16LF84A-04/P does NOT include an on-chip ADC. Designers migrating from PIC16F1xxx expect an ADC module and are surprised when the LF84A returns all zeros on analog reads. Plan for an external SPI ADC such as MCP3002 or MCP3202 for any analog sensing. Also note: RA4 is open-drain only and requires a pull-up resistor for high-level output. Finally, the 64-byte EEPROM is suitable for infrequent parameter storage, not for high-cycle log buffers.
Compliance Information
RoHS compliant per Microchip product page. Industrial temperature grade is not automotive-qualified - the PIC16LF84A-04/P is not AEC-Q100 and should not be used in automotive safety-critical applications.
