PIC18F2420-E/SP - 8-bit PIC MCU, 16KB Flash, 28-Pin SPDIP | Microchip
MPN: PIC18F2420-E/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.82 | $7.82 |
| 10 | $7.05 | $70.50 |
| 100 | $6.28 | $628.00 |
| 500 | $5.65 | $2,825.00 |
| 1,000 | $5.1 | $5,100.00 |
PIC18F2420-E/SP Overview
A PIC18 microcontroller is a member of Microchip's 8-bit Harvard-architecture MCU family, sitting between the legacy PIC16 family and the more advanced dsPIC and PIC24 16-bit lines. It uses an enhanced RISC core with C-compiler-friendly instruction set and a 16-bit instruction word, while data paths remain 8 bits wide. PIC18 MCUs are widely adopted in consumer appliances, industrial control, automotive body electronics, and USB/HID peripherals because they combine deterministic interrupt response, low power consumption, and a large ecosystem of free development tools such as MPLAB X IDE, XC8 compiler, and MPLAB PICkit programmers.
Key differentiating features of the PIC18F2420 include 16 KB self-programmable flash, 25 I/O capable of sinking/sourceing 25 mA for direct LED drive, hardware ECC on flash, and a 10-bit ADC with up to 10 channels and 100 Ksps conversion rate. The nanoWatt technology offers dynamic power-down modes (Idle, Sleep, and Deep Sleep) reducing quiescent current to under 1 uA in sleep. The internal oscillator block eliminates the need for external crystals in cost-sensitive designs while the fail-safe clock monitor automatically switches to the internal RC if the primary clock fails, allowing safe shutdown of peripherals.
Typical applications include industrial sensor interfaces, low-cost motor control (small brushed DC, stepper direction-only), home appliances, HVAC controllers, sensor hubs, USB-less HID devices, and automotive body controllers (non-safety). Designers should note the operating temperature range of -40C to +125C for the E (extended) suffix, making this part suitable for industrial and automotive under-hood environments. The SPDIP-28 package is preferred for breadboard-friendly prototypes and through-hole production.
The PIC18F2420-E/SP is best suited where 8-bit simplicity, ample legacy code base, and a 28-pin DIP footprint are required. For new designs, consider the K-series (PIC18F23K22, PIC18F24K50) for lower power and richer peripherals, or the PIC18F27/47-series for more memory; but for a true drop-in SPDIP-28 upgrade, the PIC18F2420 and PIC18F2520 (32 KB flash) variants remain in volume production. Always verify the temperature grade and packaging letter suffixes when ordering -E/SP, -I/SP, and -I/SO are different operating ranges and packages.
Drop-in alternatives for PIC18F2420-E/SP — 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 PIC18F2420-E/SP (same form factor and footprint) — differing in Package, Operating Temperature, Timers, Internal Oscillator, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F2520-E/SP
✅ Drop-In✓ In Stock
$5.1 / Unit
View Datasheet →PIC18F2420-I/SP
✅ Drop-In✓ In Stock
$5.22 / Unit
View Datasheet →PIC18F23K22-E/SP
✅ Drop-In✓ In Stock
$1.87 / Unit
View Datasheet →PIC18F24K22-E/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F25K22-E/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F2420-E/SP Maximum Ratings & Electrical Characteristics
| Product Family | PIC18F |
| Core Architecture | 8-bit enhanced Harvard RISC |
| Program Memory (Flash) | 16 KB |
| RAM | 768 bytes |
| EEPROM | 256 bytes |
| Maximum Clock Speed | 40 MHz (10 MIPS) |
| Supply Voltage (Vdd) | 4.2 V to 5.5 V |
| I/O Pins | 25 |
| ADC | 10-bit, up to 10 channels |
| Timers | 2 x 8-bit, 3 x 16-bit |
| CCP Modules | 2 |
| Communication Peripherals | EUSART (RS-232/RS-485/LIN), MSSP (SPI/I2C) |
| Package | SPDIP-28 (Skinny Plastic DIP, 0.300") |
| Mounting Type | Through-Hole |
| Operating Temperature | -40C to +125C (extended grade, "E") |
| RoHS Status | Compliant |
| Lead-Free | Yes |
| Internal Oscillator | Yes, 31 kHz to 8 MHz with PLL |
| Watchdog Timer | Yes, dedicated RC oscillator |
| Power-Saving Modes | nanoWatt (Idle, Sleep, Deep Sleep) |
PIC18F2420-E/SP Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) input / programming voltage |
| Pin 2 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Pin 4 | RA2/AN2/Vref- — PORTA bit 2 / analog input 2 / ADC Vref- |
| Pin 5 | RA3/AN3/Vref+ — PORTA bit 3 / analog input 3 / ADC Vref+ |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / analog input 4 / SPI slave select |
| Pin 8 | Vss — Ground reference |
| Pin 9 | OSC1/CLKI — Crystal oscillator input / external clock input |
| Pin 10 | OSC2/CLKO — Crystal oscillator output / clock output |
| Pin 11 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 12 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 output |
| Pin 13 | RC2/CCP1 — PORTC bit 2 / CCP1 output |
| Pin 14 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 15 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 16 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 17 | RC6/TX/CK — PORTC bit 6 / EUSART TX / clock |
| Pin 18 | RC7/RX/DT — PORTC bit 7 / EUSART RX / data |
| Pin 19 | Vss — Ground reference |
| Pin 20 | Vdd — Positive supply voltage (+5 V) |
| Pin 21 | RB0/INT0 — PORTB bit 0 / external interrupt 0 |
| Pin 22 | RB1/INT1 — PORTB bit 1 / external interrupt 1 |
| Pin 23 | RB2/INT2 — PORTB bit 2 / external interrupt 2 |
| Pin 24 | RB3/CCP2 — PORTB bit 3 / alternate CCP2 output |
| Pin 25 | RB4 — PORTB bit 4 (interrupt-on-change) |
| Pin 26 | RB5 — PORTB bit 5 (interrupt-on-change) |
| Pin 27 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 28 | RB7/PGD — PORTB bit 7 / ICSP data |
Typical Applications
PIC18F2420-E/SP is suitable for 6 applications: Industrial Sensor Interface Module, Home Appliance Control Board, Automotive Body Controller, HVAC Control System, USB-less HID Input Device, Small Motor Drive Controller.
Industrial Sensor Interface Module
The PIC18F2420-E/SP's 16 KB flash and 10-bit ADC make it well suited to multi-sensor industrial interface modules. Its 25 I/O pins allow direct connection of thermistor bridges, 4-20 mA loop sense resistors, and discrete encoders without external logic. The 40 MHz core delivers 10 MIPS, sufficient to run digital filtering on three sensor channels simultaneously, while nanoWatt sleep modes reduce quiescent current below 1 uA when the PLC bus is idle. The -40C to +125C extended temperature range supports outdoor panel-mount installation.
Recommended
Home Appliance Control Board
For washing machines, dishwashers, and small kitchen appliances, the PIC18F2420-E/SP provides the right balance of code space, timers, and PWM. Three 16-bit timers drive triac-based phase-angle control for motor speed or heating elements, while the two CCP modules generate complementary PWM for brushless DC pumps. The 25 I/O capacity connects directly to LED indicators, keypads, and 7-segment displays via charlieplexing. nanoWatt idle mode keeps standby power below 0.5 W, helping products meet EU ERP Lot 6 regulations.
Recommended
Automotive Body Controller
Within an automotive body controller (door modules, seat controllers, mirror adjusters), the PIC18F2420-E/SP handles LIN slave communication via the EUSART and 25 I/O drive window lift relays directly. The -40C to +125C operating range covers under-hood and door-mounted electronics. Watchdog timer with dedicated RC oscillator ensures the MCU recovers from voltage transients on the 12 V battery rail, and fail-safe clock monitor keeps the LIN bus synchronised even during cranking pulses. 16 KB of flash is sufficient for typical seat-memory and door-lock logic.
Recommended
HVAC Control System
Heating, ventilation, and air-conditioning controllers benefit from the PIC18F2420-E/SP's 10-bit ADC for temperature/humidity sensing and three 16-bit timers for triac phase control of dampers and compressor relays. The 768-byte RAM accommodates proportional-integral control loops for two-zone climate regulation, while 256 bytes of EEPROM stores setpoint schedules across power cycles. The PIC18 core's deterministic interrupt response keeps servo loop jitter under 5 us for stable damper position.
Recommended
USB-less HID Input Device
For keyboards, mice, gaming controllers, and custom HID devices that do not require USB, the PIC18F2420-E/SP provides 25 scan lines for 8x8 matrix keypads and onboard PS/2 or proprietary serial output via the EUSART. The 40 MHz CPU polls a 64-key matrix in under 100 us with full N-key rollover detection, while 768 bytes RAM holds debounce state. nanoWatt sleep mode drops current to sub-microamp when the device is idle, extending battery life in wireless HID dongles.
Recommended
Small Motor Drive Controller
Stepper motors, small brushless DC fans, and brushed DC gear-motors can be driven directly by the PIC18F2420-E/SP's two CCP/PWM modules and 25 mA I/O. Software-generated center-aligned PWM at 20 kHz keeps stepper motors quiet, while hardware timers handle back-EMF zero-crossing for sensorless BLDC commutation. The extended temperature grade allows under-hood cooling-fan control, and 16 KB flash fits space-vector and trapezoidal commutation tables for 6-step BLDC algorithms.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F2420-E/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F2520-E/SP | PIC18F2420-I/SP | PIC18F23K22-E/SP | PIC18F24K22-E/SP |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SPDIP-28 | SPDIP-28 - same | SPDIP-28 - same | SPDIP-28 - same | SPDIP-28 - same |
| Flash Memory | 16 KB | 32 KB | 16 KB | 8 KB | 16 KB |
| RAM | 768 bytes | 1536 bytes | 768 bytes | 512 bytes | 768 bytes |
| Maximum Clock | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 64 MHz (16 MIPS) | 64 MHz (16 MIPS) |
| Operating Temperature | -40C to +125C | -40C to +125C | -40C to +85C | -40C to +125C | -40C to +125C |
| ADC Resolution | 10-bit, 10 channels | 10-bit, 10 channels | 10-bit, 10 channels | 12-bit, 19 channels | 12-bit, 19 channels |
| Internal Oscillator | 8 MHz with PLL | 8 MHz with PLL | 8 MHz with PLL | 16 MHz HF + 32 kHz LF | 16 MHz HF + 32 kHz LF |
Key Differentiators
- Largest flash in PIC18F2420 SPDIP-28 family at low cost (vs PIC18F23K22-E/SP)
- Extended temperature grade with no premium pricing (vs PIC18F2420-I/SP)
- Backward-compatible peripheral set with 10 MIPS headroom (vs PIC18F24K22-E/SP)
Design Notes
Power the PIC18F2420-E/SP from a regulated 5 V supply; the MCU draws approximately 16 mA at 40 MHz active, dropping to 1 uA in Sleep. Place a 100 nF decoupling capacitor within 5 mm of Vdd (pin 20) and a 10 uF bulk capacitor near the SPDIP-28 supply pins. If using analog references, add 100 nF on Vref+ (pin 5) to suppress ADC switching noise. The /MCLR pin (1) must be tied to Vdd via a 10 kohm pull-up for normal operation; add a diode to Vdd for ICSP programming.
Route the OSC1/OSC2 traces short and symmetric when using a crystal; place the crystal within 5 mm of the pins and guard it with a ground pour to suppress EMI. Keep ADC traces away from PWM and digital switching signals; use a separate analog ground island tied to Vss at a single point. For breadboard prototypes, the SPDIP-28 package is ideal, but for production consider migrating to SOIC-28 (PIC18F2420-E/SO) or QFN-28 (PIC18F2420-E/ML) for better thermal performance and reduced footprint.
Do not assume the configuration bits default to internal oscillator - the PIC18F2420 must be configured for the desired Fosc via CONFIG1H before code will execute. Always set the WDT (watchdog timer) explicitly; relying on its default-off state leaves the system vulnerable to runaway code. When migrating from -I to -E temperature grade, verify that all analog peripherals have published specs across the full -40C to +125C range. Finally, do not exceed 25 mA source/sink per I/O pin or 200 mA total PORTB current to avoid latch-up.
Estimated: at 40 MHz active, 5 V supply, and full I/O drive, the SPDIP-28 package dissipates approximately 200 mW internally. The junction-to-ambient thermal resistance (theta_JA) of SPDIP-28 is approximately 70 C/W, yielding a junction temperature rise of 14 C above ambient - well within the 125 C operating ceiling. No heatsink is required. However, in enclosed IP65 enclosures at 85 C ambient, consider derating to 32 MHz or implementing Sleep modes between measurements.
Compliance Information
RoHS compliant per Microchip product page; REACH SVHC declarations current as of 2026-09-26. Not AEC-Q100 qualified - this part targets industrial and consumer, not automotive safety-critical; for AEC-Q100 consider PIC18F25K80-E/SO.
