PIC16LF84-04I/SO - 4MHz 8-bit Flash MCU 1.75KB | Microchip
MPN: PIC16LF84-04I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.94 | $7.94 |
| 10 | $7.2 | $72.00 |
| 100 | $6.45 | $645.00 |
| 500 | $5.7 | $2,850.00 |
| 1,000 | $5.05 | $5,050.00 |
PIC16LF84-04I/SO Overview
An 8-bit PIC microcontroller (MCU) is a small, low-power, single-chip computer built around a Harvard RISC core. It integrates CPU, non-volatile program memory (Flash), volatile data memory (RAM), non-volatile EEPROM data, and peripherals (I/O, timers, interrupts) into one IC. PIC16 MCUs sit in the PIC mid-range family between 8-pin baseline devices and 16-bit dsPIC parts, forming the workhorse tier of Microchip's 8-bit MCU lineup for general-purpose embedded control.
Key features include 13 digital I/O pins, 64 bytes of EEPROM data memory, a 14-bit instruction word, a hardware 8-bit timer/counter (TMR0) with watchdog, four oscillator modes (RC, LP, XT, HS), and an industrial temperature range of -40C to +85C. The "LF" voltage range supports 2.0V to 5.5V operation, enabling battery-powered designs, while the "-04" speed grade specifies a 4 MHz oscillator maximum and the "I" suffix marks the industrial temperature grade.
The PIC16LF84 architecture uses a 14-bit wide Flash program path and an 8-bit data path, with a separate 8-bit-wide EEPROM array. The Harvard bus and single-cycle instruction fetch deliver deterministic throughput important for time-sensitive tasks such as bit-banged protocols or fixed-frequency PWM control. Brown-out and power-on reset, plus the watchdog timer, give the LF84 robust autonomous startup and recovery behavior for unattended sensors and appliances.
Typical applications include low-power remote sensors, hobbyist/learner boards (the LF84 is the classic Microchip training part), battery-backed appliance controllers, simple logic-replacement glue, and legacy industrial control retrofits. Designers also pick this part when migrating older PIC16C5x/PIC16F84A firmware forward into a low-voltage variant.
When designing, observe the recommended 1uF/22pF power decoupling layout and place a 33 pF to 10 pF capacitor on OSC1/OSC2 for crystal oscillator mode. Ensure Vdd rise time for the power-on reset stays within the datasheet limits, and reserve one I/O pin for the MCLR/Vpp programming interface if in-circuit serial programming is required.
This page synthesizes distributor stock, parametric drop-in alternatives in the same 18-SOIC footprint, and practical design considerations that go beyond what the manufacturer datasheet alone provides.
Drop-in alternatives for PIC16LF84-04I/SO — 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 PIC16LF84-04I/SO (same form factor and footprint) — differing in Core Architecture, Package, Program Memory, Timers, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F84A-04I/SO
✅ Drop-In✓ In Stock
$3.59 / Unit
View Datasheet →PIC16F84-04/SO
✅ Drop-In✓ In Stock
$3.19 / Unit
View Datasheet →PIC16LF84T-04I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF84AT-04I/SO
✅ Drop-In✓ In Stock
$1.95 / Unit
View Datasheet →PIC16F84A-04/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LF84-04I/SO Maximum Ratings & Electrical Characteristics
| Core | PIC16 8-bit RISC |
| Program Memory | 1.75 KB Flash (1K x 14) |
| RAM | 68 bytes |
| EEPROM | 64 bytes |
| Maximum Clock Frequency | 4 MHz |
| Instruction Cycle | 200 ns (1 cycle, 2 for branches) |
| Instruction Set Size | 35 single-word instructions |
| I/O Pins | 13 |
| Operating Voltage (LF) | 2.0 V to 5.5 V |
| Timers | TMR0 8-bit timer/counter with WDT |
| Oscillator Modes | RC, LP, XT, HS |
| Operating Temperature | -40C to +85C (industrial, "I" suffix) |
| Package | 18-pin SOIC (SO), 7.50 mm width |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited) |
PIC16LF84-04I/SO Pin Configuration
| Pin 1 | RA2 — GPIO port A bit 2 |
| Pin 2 | RA3 — GPIO port A bit 3 |
| Pin 3 | RA4/T0CKI — GPIO port A bit 4 / TMR0 clock input |
| Pin 4 | MCLR/Vpp — Master clear reset (active low) / programming voltage |
| Pin 5 | Vss — Ground reference |
| Pin 6 | RB0/INT — GPIO port B bit 0 / external interrupt |
| Pin 7 | RB1 — GPIO port B bit 1 |
| Pin 8 | RB2 — GPIO port B bit 2 |
| Pin 9 | RB3 — GPIO port B bit 3 |
| Pin 10 | RB4 — GPIO port B bit 4 (interrupt-on-change) |
| Pin 11 | RB5 — GPIO port B bit 5 (interrupt-on-change) |
| Pin 12 | RB6 — GPIO port B bit 6 (interrupt-on-change / ICSP clock) |
| Pin 13 | RB7 — GPIO port B bit 7 (interrupt-on-change / ICSP data) |
| Pin 14 | Vdd — Positive supply voltage (2.0V-5.5V) |
| Pin 15 | OSC2/CLKOUT — Oscillator crystal output / clock output FOSC/4 |
| Pin 16 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 17 | RA0 — GPIO port A bit 0 |
| Pin 18 | RA1 — GPIO port A bit 1 |
Typical Applications
PIC16LF84-04I/SO is suitable for 6 applications: Battery-Powered Remote Sensor Node, Hobbyist and Educational Development Board, Appliance Controller Replacement Board, Legacy Logic-Replacement and Glue IC, Industrial Sensor Signal Conditioning, Automotive Interior Accessory Module.
Battery-Powered Remote Sensor Node
The PIC16LF84-04I/SO is well-suited for low-duty-cycle remote sensors because of its 2.0V-5.5V operating range and modest 4 MHz clock. Sleep current drops into the microamp range with the watchdog disabled, allowing 2x AA cells to last years on a 1% measurement duty cycle. The 13 GPIO can drive a low-power radio enable line, an analog sensor MUX, and an interrupt-based wake source, all while leaving 1.75 KB of Flash for application logic and 64 bytes of EEPROM for calibration constants that survive battery swaps.
Recommended
Hobbyist and Educational Development Board
The PIC16LF84-04I/SO is the canonical Microchip training part and a default MCU on classic PIC16 trainer boards. Its 35 single-word instructions are teachable in a single lab session, while the 200 ns instruction cycle is short enough to demonstrate bit-banging and timer-based delays in real time. The 18-SOIC footprint is breadboard-friendly with an SOIC-to-DIP adapter, and ICSP via MCLR/Vpp allows in-circuit programming without removing the chip, ideal for classroom settings where learners iterate fast.
Recommended
Appliance Controller Replacement Board
The PIC16LF84-04I/SO fits appliance control retrofits (small kitchen, HVAC actuators, washing-machine user interface panels) because of its industrial -40C to +85C temperature range and deterministic single-cycle core. Hardware timers, the watchdog, and brown-out reset provide unattended-recovery behavior required for safety-critical appliances. The 13 GPIO handle keypad scan, LED drivers, and relay control, while the 64-byte EEPROM stores user settings and error logs across power cycles, replacing legacy PIC16C5x designs with modern flash in-circuit programmability.
Recommended
Legacy Logic-Replacement and Glue IC
The PIC16LF84-04I/SO works as a programmable glue IC for replacing scattered discrete logic in legacy industrial panels. With 13 GPIO, configurable interrupts on RB0/INT, and timer-driven sequencing, a single LF84 can replace 3-4 logic packages (decoders, monostables, latches). Its 2.0V-5.5V range matches both 3.3V and 5V logic families, while Flash storage allows late-stage firmware updates via ICSP. Engineers can prototype with a development board, then freeze the code and ship the LF84 as a single-chip replacement.
Recommended
Industrial Sensor Signal Conditioning
The PIC16LF84-04I/SO handles signal conditioning for slow industrial sensors such as thermistors, strain gauges, and reed switches. Its 13 GPIO can implement software PWM for excitation, comparator-based threshold detection, and serial bit-banged output to a host PLC. The 64-byte EEPROM retains calibration constants, while the watchdog timer recovers from EMI-induced latchups in factory-floor installations. Industrial -40C to +85C operation and the 18-SOIC surface-mount package fit dense PLC backplane designs.
Recommended
Automotive Interior Accessory Module
The PIC16LF84-04I/SO is appropriate for non-safety automotive interior accessories such as ambient lighting controllers, seat-position memories, and accessory timers. While the -04I part only reaches -40C to +85C (not full -40C to +125C automotive Grade 1), it remains usable in cabin environments. The 13 GPIO drive LED PWM channels and switches, while the EEPROM stores user-preset positions. Designers wanting true automotive qualification should choose PIC16F84A-E/SO extended-temp variants or upgrade to PIC16F886-class parts.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LF84-04I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F84A-04I/SO | PIC16F84-04/SO | PIC16LF84T-04I/SO | PIC16LF84AT-04I/SO | PIC16F84A-04/SO |
|---|---|---|---|---|---|---|
| Package | SOIC-18 | SOIC-18 (same) | SOIC-18 (same) | SOIC-18 (same) | SOIC-18 (same) | SOIC-18 (same) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 1.75 KB Flash (1K x 14) | 1.75 KB Flash | 1.75 KB Flash | 1.75 KB Flash | 1.75 KB Flash | 1.75 KB Flash |
| RAM | 68 bytes | 128 bytes (+88%) | 68 bytes | 68 bytes | 128 bytes | 128 bytes |
| EEPROM | 64 bytes | 64 bytes | 64 bytes | 64 bytes | 64 bytes | 64 bytes |
| Operating Voltage | 2.0V to 5.5V (LF) | 2.0V to 5.5V (LF) | 4.0V to 5.5V (F) | 2.0V to 5.5V (LF) | 2.0V to 5.5V (LF) | 4.0V to 5.5V (F) |
| Temperature Grade | Industrial -40C to +85C | Industrial -40C to +85C | Commercial 0C to +70C | Industrial -40C to +85C | Industrial -40C to +85C | Commercial 0C to +70C |
| Hardware USART | No | Yes | No | No | Yes | Yes |
| Maximum Clock | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
Key Differentiators
- Wider operating voltage for battery-powered designs (vs PIC16F84-04/SO)
- Industrial temperature grade (vs PIC16F84-04/SO)
- Lower-cost legacy alternative for non-A-revision designs (vs PIC16F84A-04I/SO)
- Smaller RAM keeps power footprint minimal (vs PIC16F84A-04I/SO)
Design Notes
Decouple Vdd (pin 14) with a 100 nF ceramic capacitor placed within 5 mm of the supply pin, with a parallel 10 uF bulk capacitor on the same rail. The PIC16LF84-04I/SO shares its Vdd/Vss pair across the entire core; insufficient decoupling can cause spurious brown-out resets during oscillator startup or EEPROM write cycles.
Place a 22 pF to 33 pF load capacitor on each of OSC1 (pin 16) and OSC2 (pin 15) for crystal operation, sized to match the crystal manufacturer's load capacitance specification (CL = (C1 x C2) / (C1 + C2) + Cstray). Keep the crystal traces short and surround them with a ground pour to minimise noise injection into the high-impedance oscillator amplifier.
Ensure the MCLR/Vpp pin (pin 4) is tied to Vdd through a 10 kohm pull-up resistor and decoupled with a 100 nF cap during normal operation, but is accessible to the programmer for in-circuit serial programming (ICSP). Failure to correctly bias MCLR is a frequent cause of erratic resets and ICSP failures. For low-power designs, do not leave MCLR floating - it has an internal filter but external pull-up is mandatory for noise immunity.
Route the ICSP signals RB6 (pin 12) and RB7 (pin 13) with no series resistors to the programming header - the PIC16LF84 expects direct drive from the ICSP tool during programming. Adding a series resistor breaks the high-voltage Vpp hand-off and prevents successful flashing. Keep RB6/RB7 accessible from the programming header even if they are used for application GPIO, by routing through test points or zero-ohm jumpers.
Compliance Information
Compliance fields not explicitly stated in the verified distributor data; consult Microchip product environmental compliance page for authoritative RoHS/REACH declarations on PIC16LF84-04I/SO. Industrial temp grade does not imply AEC-Q100 automotive qualification.
