PIC18F45K20-I/PT - 8-bit 64MHz XLP MCU, 32KB Flash, 44-TQFP
MPN: PIC18F45K20-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.85 | $4.85 |
| 10 | $4.12 | $41.20 |
| 100 | $3.6 | $360.00 |
| 500 | $3.21 | $1,605.00 |
| 1,000 | $2.95 | $2,950.00 |
PIC18F45K20-I/PT Overview
What is a microcontroller? A microcontroller (MCU) is a single-chip computer that integrates a CPU, non-volatile program memory (Flash), working memory (RAM), and a range of peripherals - timers, ADC, communication ports, and I/O - onto one die. The PIC18F family specifically uses a RISC Harvard-architecture core with 16-bit instructions and 8-bit data paths, favored for deterministic interrupt response in industrial control. Within Microchip's portfolio, the PIC18F45K20 sits at the intersection of the 8-bit 'F' series and the nanoWatt XLP technology node, positioned above the PIC16F and below the dsPIC33 line.
Key features include 64 MHz maximum clock from an internal 16 MHz oscillator or external crystal, 36 digital I/O pins, a 10-bit ADC with up to 14 channels, two analog comparators, two CCP/ECCP modules, two EUSART, MSSP (SPI/I2C), and a wide operating voltage range from 1.8 V to 5.5 V. The device also supports self-programmability and an on-chip 16-level hardware stack.
Typical applications include low-power sensor nodes, USB-to-UART bridges using the EUSART, white-goods control boards, industrial meters, LED lighting controllers, and consumer devices requiring long battery life. The wide voltage range supports direct operation from lithium-thionyl-chloride (3.6 V) primary cells used in utility metering.
When designing with this part, choose MPLAB X IDE with XC8 compiler and PICkit 3/4 for in-circuit debug. For lowest sleep power, switch off the ADC and disable unused peripherals via the PMD registers and use the RTCC with an external 32.768 kHz crystal for timekeeping. This page consolidates datasheet specs, drop-in compatible variants, distributor pricing, and engineering notes not assembled in any single manufacturer document.
Drop-in alternatives for PIC18F45K20-I/PT — 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 PIC18F45K20-I/PT (same form factor and footprint) — differing in Package, Core Architecture, Timers, ADC, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F45K22-I/PT
✅ Drop-In✓ In Stock
$2.65 / Unit
View Datasheet →PIC18F45K40-I/PT
✅ Drop-In✓ In Stock
$1.34 / Unit
View Datasheet →PIC18F4520-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F44K20T-I/PT
✅ Drop-In✓ In Stock
$3.49 / Unit
View Datasheet →PIC18F46K22-I/PT
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F45K20-I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 (8-bit RISC, Harvard) |
| Family | PIC18F K-series with nanoWatt XLP |
| Program Memory (Flash) | 32 KB (16K x 16 words) |
| SRAM | 1536 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Clock | 64 MHz (16 MIPS via 4x PLL) |
| Operating Voltage (VDD) | 1.8 V to 5.5 V |
| I/O Pins | 36 |
| ADC | 10-bit, up to 14 channels |
| Comparators | 2 (with selectable reference) |
| CCP / ECCP Modules | 1 CCP + 1 ECCP (PWM) |
| EUSART | 2 |
| MSSP (SPI / I2C) | 1 |
| Timers | 4 (Timer0, Timer1, Timer2, Timer3) |
| Package | 44-pin TQFP (PT), 10x10 mm |
| Operating Temperature (Industrial) | -40 C to +85 C |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| RoHS Status | Compliant |
| Lead-Free (Pb-free) | Yes |
PIC18F45K20-I/PT Pin Configuration
| Pin 1 | RA2/AN2 — Digital I/O RA2 / analog channel 2 |
| Pin 2 | RA3/AN3/VREF+ — Digital I/O RA3 / analog channel 3 / ADC positive reference |
| Pin 3 | RA4/T0CKI/RCV — Digital I/O RA4 / Timer0 clock input / EUSART1 RCV |
| Pin 4 | RA5/AN4/SS1/HLVDIN — Digital I/O RA5 / AN4 / MSSP1 Slave Select / High/Low-Voltage Detect input |
| Pin 5 | Vss — Ground reference |
| Pin 6 | OSC1/CLKIN/RA7 — Crystal oscillator input / external clock / RA7 |
| Pin 7 | OSC2/CLKOUT/RA6 — Crystal oscillator output / clock out / RA6 |
| Pin 8 | Vdd — Positive supply voltage (1.8 V - 5.5 V) |
| Pin 9 | RB0/AN12 — Digital I/O RB0 / analog channel 12 / INT0 |
| Pin 10 | RB1/AN10 — Digital I/O RB1 / analog channel 10 / INT1 |
| Pin 11 | RB2/AN8 — Digital I/O RB2 / analog channel 8 / INT2 |
| Pin 12 | RB3/AN9 — Digital I/O RB3 / analog channel 9 / INT3 |
| Pin 13 | NC — No connect (reserved) |
| Pin 14 | RB4/AN11 — Digital I/O RB4 / analog channel 11 / IOC |
| Pin 15 | RB5/AN13 — Digital I/O RB5 / analog channel 13 / IOC |
| Pin 16 | RB6/PGC — Digital I/O RB6 / ICD clock line (PGC) |
| Pin 17 | RB7/PGD — Digital I/O RB7 / ICD data line (PGD) |
| Pin 18 | NC — No connect (reserved) |
| Pin 19 | Vss — Ground reference (second analog/digital GND) |
| Pin 20 | VDDCORE/VCAP — Internal regulator output / decoupling cap to Vss |
| Pin 21 | RB8/AN14 — Digital I/O RB8 / analog channel 14 |
| Pin 22 | RB9/AN15 — Digital I/O RB9 / analog channel 15 |
| Pin 23 | RB10/AN16 — Digital I/O RB10 / analog channel 16 |
| Pin 24 | RB11/AN17 — Digital I/O RB11 / analog channel 17 |
| Pin 25 | RC0/T1OSO/T1CKI — Digital I/O RC0 / Timer1 oscillator output / Timer1 clock input |
| Pin 26 | RC1/T1OSI/CCP2 — Digital I/O RC1 / Timer1 oscillator input / Enhanced CCP2 PWM |
| Pin 27 | RC2/CCP1 — Digital I/O RC2 / Enhanced CCP1 PWM |
| Pin 28 | RC3/SCL1/SCK1 — Digital I/O RC3 / I2C1 clock / MSSP1 SPI clock |
| Pin 29 | RD0 — Digital I/O RD0 |
| Pin 30 | RD1 — Digital I/O RD1 |
| Pin 31 | RD2 — Digital I/O RD2 |
| Pin 32 | RD3 — Digital I/O RD3 |
| Pin 33 | RC4/SDA1/SDI1 — Digital I/O RC4 / I2C1 data / MSSP1 SPI data in |
| Pin 34 | RC5/SDO1 — Digital I/O RC5 / MSSP1 SPI data out |
| Pin 35 | RC6/TX1/CK1 — Digital I/O RC6 / EUSART1 TX / EUSART1 clock |
| Pin 36 | RC7/RX1/DT1 — Digital I/O RC7 / EUSART1 RX / EUSART1 data |
| Pin 37 | RD4 — Digital I/O RD4 |
| Pin 38 | RD5 — Digital I/O RD5 |
| Pin 39 | RD6/TX2/CK2 — Digital I/O RD6 / EUSART2 TX |
| Pin 40 | RD7/RX2/DT2 — Digital I/O RD7 / EUSART2 RX |
| Pin 41 | RE0/RD — Digital I/O RE0 / Parallel-port Read strobe |
| Pin 42 | RE1/WR — Digital I/O RE1 / Parallel-port Write strobe |
| Pin 43 | RE2/CS — Digital I/O RE2 / Parallel-port Chip Select |
| Pin 44 | AVDD — Analog positive supply (tie to VDD) |
Typical Applications
PIC18F45K20-I/PT is suitable for 7 applications: Battery-Powered Wireless Sensor Node, Industrial Control Panel (HMI/Operator Interface), Smart Metering and Utility Data Logger, White Goods and Home Appliance Control, Automotive Interior Lighting and Body Control, USB-to-Serial Bridge and Field Updater, LED Lighting and Signage Controllers.
Battery-Powered Wireless Sensor Node
The PIC18F45K20-I/PT is a strong fit for battery-powered sensor nodes thanks to its nanoWatt XLP Sleep current below 100 nA and 1.8 V minimum VDD that runs directly from a single lithium thionyl-chloride 3.6 V primary cell. The 1536-byte SRAM is sufficient for Modbus RTU or proprietary sensor framing, while the 14-channel 10-bit ADC handles multiple analog sensors with internal voltage reference. The on-chip EUSART supports RS-485 or 4-20 mA loop links. Compared with an ATmega or STM8 alternative, the K20 typically achieves a 5-10x longer battery life on the same cell because Sleep-mode leakage is dominated by the MCU, not the radio.
Recommended
Industrial Control Panel (HMI/Operator Interface)
The PIC18F45K20-I/PT drives small industrial control panels and HMI keypads using its 36 I/O pins, two EUSART links to RS-485 Modbus slaves, and the ECCP module for backlight PWM. Its wide 1.8-5.5 V VDD range supports operation from raw 24 V industrial buses after a small switching pre-regulator. The 16 MIPS throughput enables fast debounce and button-matrix handling without an external controller. Compared with PIC18F4550 (USB-enabled) or dsPIC33 (DSP), the K20 cuts cost and current draw when USB is unnecessary.
Recommended
Smart Metering and Utility Data Logger
Utilities running millions of metering endpoints select the PIC18F45K20-I/PT for its 1.5 KB SRAM, RTC support, and ultra-low Sleep current, all of which are critical for battery-life targets of 10+ years. The integrated ECCP and 16-bit timers enable accurate pulse counting from mechanical meter registers, while the 10-bit ADC records sensor inputs such as flow or temperature. The 32 KB Flash fits an Open Metering Standard (OMS) stack plus drivers. Compared with PIC24 or ARM Cortex-M0 alternatives, the 8-bit K20 dramatically reduces IC cost while still meeting Class 1 metering accuracy.
Recommended
White Goods and Home Appliance Control
Washing machines, dishwashers, and induction cooktops use the PIC18F45K20-I/PT for appliance control thanks to its ECCP for PWM motor drive, 14-channel ADC for thermistor and water-level sensing, and rugged -40 to +85 C industrial rating. The 64 MHz core executes triac-zero-crossing algorithms with sub-millisecond jitter, eliminating flicker and audible noise. Compared with legacy F-series, the K20's nanoWatt XLP Sleep mode cuts standby power well below the 0.5 W EuP/WEEE limit. The same firmware migrates across the PIC18F45K20 / 46K22 family without changes.
Recommended
Automotive Interior Lighting and Body Control
The PIC18F45K20-I/PT can drive automotive interior LED lighting, mirror controllers, and seat-position logic. Although not AEC-Q100 itself, the -40 to +125 C automotive-grade equivalent (PIC18F45K20-I/PT extended temp variants) is widely deployed in low-volt body control modules (BCMs). The ECCP module provides PWM fade-in/out, while the comparators handle current-sense monitoring. Compared with PIC16F or PIC10F parts, the 40-pin-package K20 gives designers headroom for feature expansion without changing package.
Recommended
USB-to-Serial Bridge and Field Updater
Boards that need a USB host or device interface often pair the PIC18F45K20-I/PT with the MCP2200 USB-to-UART chip, leveraging the device's two EUSARTs to bridge USB to RS-232/485 sensor stacks. The 32 KB Flash holds both the bridge firmware and a small bootloader for field upgrades via the same UART pair. The 1.5 KB SRAM and 16 MIPS make command parsing reliable at 921.6 kbaud. Compared with the older PIC18F2455/4550 part, the K20 lacks native USB but gains XLP Sleep for battery-powered bridges, with much longer shelf life.
Recommended
LED Lighting and Signage Controllers
PIC18F45K20-I/PT controllers manage individually-addressable WS2812B LED strings and high-density DMX-512 lighting fixtures using its 64 MHz core for tight WS2812B bit-banging and EUSART for DMX data. The ECCP provides 16-bit PWM for white-LED dimming. The XLP Sleep mode suits battery-tethered decorative lighting controllers. Compared with legacy 16-bit PIC24FJ parts, the K20 has lower Bill-of-Materials cost while still delivering artifact-free visual refresh at up to 800 kHz pixel clock.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F45K20-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F45K22-I/PT | PIC18F45K40-I/PT | PIC18F4520-I/PT | PIC18F44K20T-I/PT | PIC18F46K22-I/PT |
|---|---|---|---|---|---|---|
| Package | TQFP-44 (PT) 10x10 mm | TQFP-44 (PT) 10x10 mm - same | TQFP-44 (PT) 10x10 mm - same | TQFP-44 (PT) 10x10 mm - same | TQFP-44 (PT) 10x10 mm - same | TQFP-44 (PT) 10x10 mm - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash | 32 KB | 32 KB | 32 KB | 32 KB | 16 KB | 64 KB |
| SRAM | 1.5 KB | 1.5 KB | 2 KB | 1.5 KB | 768 B | 3.9 KB |
| Maximum Clock | 64 MHz | 64 MHz | 64 MHz | 40 MHz | 64 MHz | 64 MHz |
| Minimum VDD | 1.8 V | 1.8 V | 1.8 V | 2.0 V | 1.8 V | 1.8 V |
| nanoWatt XLP | Yes (Sleep < 100 nA) | Yes (Sleep < 100 nA) | Yes (Sleep < 100 nA) | No (legacy F-series) | Yes (Sleep < 100 nA) | Yes (Sleep < 100 nA) |
| ADC | 10-bit, 14 ch | 10-bit, 14 ch | 12-bit ADC, 35 ch | 10-bit, 8 ch | 10-bit, 11 ch | 10-bit, 16 ch |
| Operating Temperature | -40 C to +85 C (industrial) | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
Key Differentiators
- nanoWatt XLP Sleep current under 100 nA, vs several microamperes on legacy F-series (vs PIC18F4520-I/PT)
- 1.8 V minimum VDD operation versus 2.0 V on F-series (vs PIC18F4520-I/PT)
- 64 MHz / 16 MIPS core vs 40 MHz / 10 MIPS on PIC18F4520 (vs PIC18F4520-I/PT)
- Core Independent Peripherals (CLC, NCO) on later drop-ins but NOT on K20 (vs PIC18F45K22-I/PT)
Design Notes
Estimated: for Sleep-mode bill-of-materials selection on a 3.6 V Thionyl-chloride cell, the K20's XLP Sleep current is below 100 nA per Microchip datasheet 41303F. Keep all peripherals off via PMD bits before WFI, and gate the EUSART 32.768 kHz crystal with a MOSFET if it is not continuously required. A 10 uF decoupling cap at VDD plus a 100 nF ceramic at VCAP pins is mandatory. Disabling FVR and unused comparators typically saves an additional 6-10 uA in active mode - meaningful for battery-powered metering.
Place a 100 nF ceramic decoupling capacitor within 3 mm of each VDD/Vss pair. For the 44-TQFP package there are two VDD pins (pin 8 and pin 11 or RA-side) and two Vss pins; both must be decoupled. The VCAP pin (20) needs a 100 nF / 1 uF cap. Keep high-speed traces such as the ICP programming lines (PGC/PGD) short (under 50 mm), and route the 32.768 kHz crystal traces as a guarded differential pair with Vss hatch. A four-layer board with continuous ground plane reduces EMI on the PLL outputs.
Estimated: if your PIC18F45K20-I/PT firmware uses the ADC, ensure the AVDD/VREF- pins are populated; ignoring them is the most common bring-up failure. The internal oscillator is factory-trimmed but you should re-set the OSCTUNE.PLLEN bit if you need 64 MHz, and configure SCS<1:0> correctly when switching from the internal oscillator to a 32.768 kHz crystal for RTCC. When migrating from PIC18F4520 to K20, do NOT assume legacy 5 V parameters - the K20 VOH/IOH specs differ at 1.8 V. Finally, the 'I' industrial temperature range is -40 C to +85 C; for -40 C to +125 C automotive parts, use the E suffix (PIC18F45K20-E/PT).
Compliance Information
Industrial grade (-40 C to +85 C). For AEC-Q100 automotive designs, choose PIC18F45K22-E/PT or PIC18F46K22-E/PT automotive-qualified variants.