PIC18F24K50T-I/ML - 8-bit USB MCU 16KB Flash 48MHz | Microchip
MPN: PIC18F24K50T-I/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.95 | $2.95 |
| 10 | $2.66 | $26.60 |
| 100 | $2.35 | $235.00 |
| 500 | $2.1 | $1,050.00 |
| 1,000 | $1.85 | $1,850.00 |
PIC18F24K50T-I/ML Overview
An 8-bit microcontroller (MCU) is a small, self-contained computer-on-a-chip that combines a CPU, memory (Flash, RAM, EEPROM), and peripherals on a single die. The PIC18 family is Microchip's mid-range 8-bit architecture, positioned between the baseline PIC10/12/16 family and the high-performance PIC24/dsPIC families. 8-bit MCUs serve cost- and power-sensitive embedded roles where ARM Cortex-M parts are overkill - appliances, sensor hubs, USB peripherals, and consumer devices. Compared with discrete logic, an integrated MCU reduces BOM, PCB area, and firmware complexity by replacing multiple timers, ADCs, and glue logic.
Key features of the PIC18F24K50 include 16 KB Flash, 2 KB RAM, 256 B EEPROM, a 10-bit ADC with up to 14 channels, two 8-bit and two 16-bit timers, two comparators, and a full-speed USB 2.0 device transceiver with internal pull-up. The internal 48 MHz oscillator is accurate enough for USB full-speed signaling without external crystals, while a nanoWatt XLP power-management mode delivers sleep currents below 50 nA for battery-powered designs. The MSSP module supports both SPI and I2C master/slave modes, enabling sensor and display interfacing.
Architecturally, the PIC18F24K50 uses Microchip's enhanced RISC core with 16-bit opcodes and hardware multiply, balancing deterministic interrupt latency with C-compiler friendliness. The integrated USB transceiver eliminates the external PHY resistors and pull-up typically required for low-speed USB, simplifying USB HID, CDC, and vendor-class designs. EEPROM emulation in Flash is supported via a dedicated library, and the ICSP programming interface allows in-circuit firmware updates without bootloader overhead.
Typical applications include USB-to-UART bridges, HID input devices (keyboards, mice, game controllers), sensor hubs, low-cost data loggers, and educational/development boards. The wide 2.5V-5.5V range allows direct bus-power operation from 3.3V or 5V systems without additional regulators.
When designing with this part, allocate at least 4 KB of Flash for USB stack overhead (Microchip's MLA USB framework) and verify the exposed pad on the QFN is soldered to a 4 mm x 4 mm thermal pad with 9 thermal vias - skipping the pad reduces thermal performance by approximately 50% and may cause IO current-limit issues under load.
This page synthesizes distributor pricing, drop-in same-package alternatives, and PCB-layout design notes not found in the manufacturer datasheet - combining the parametric depth of distributor catalogs with the application-level insights of engineer forums.
Drop-in alternatives for PIC18F24K50T-I/ML — 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 PIC18F24K50T-I/ML (same form factor and footprint) — differing in I/O Pins, Operating Temperature, Package, Program Memory (Flash), Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F24K50-I/ML
✅ Drop-In✓ In Stock
$1.95 / Unit
View Datasheet →PIC18F24K50T-I/SS
✅ Drop-In✓ In Stock
$2.95 / Unit
View Datasheet →PIC18F24K50-E/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F24J50T-I/ML
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.88 / Unit
View Datasheet →PIC18F24K40T-I/ML
✅ Drop-In✓ In Stock
$1.22 / Unit
View Datasheet →PIC18F24K50T-I/ML Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 (8-bit RISC) |
| Program Memory (Flash) | 16 KB |
| Data RAM | 2 KB |
| EEPROM | 256 B |
| Maximum CPU Frequency | 48 MHz (16 MIPS) |
| Supply Voltage Range | 2.5 V to 5.5 V |
| Operating Temperature Range | -40 C to +85 C (Industrial) |
| Package | 28-pin QFN (ML) 6x6 mm |
| Mounting Type | Surface Mount |
| USB Module | USB 2.0 Full-Speed Device, internal transceiver |
| ADC | 10-bit, up to 14 channels |
| Timers | 2 x 8-bit, 2 x 16-bit |
| Communication Interfaces | USB, UART, SPI, I2C (MSSP), I2S |
| Comparators | 2 |
| CCP/ECCP Modules | 1 CCP + 1 ECCP |
| I/O Pins | Up to 25 |
| MSL Level | 3 (168 hours) |
| RoHS Status | Compliant |
| Programming Interface | ICSP (In-Circuit Serial Programming) |
PIC18F24K50T-I/ML Pin Configuration
| Pin 1 | RA2 — Digital I/O / analog input AN2 / CVREF |
| Pin 2 | RA3 — Digital I/O / analog input AN3 / VREF+ |
| Pin 3 | RA4 — Digital I/O / analog input AN4 / T0CKI |
| Pin 4 | RA5 — Digital I/O / analog input AN5 / HLVDIN |
| Pin 5 | VSS — Ground |
| Pin 6 | RA7 — Digital I/O / oscillator output |
| Pin 7 | RA6 — Digital I/O / oscillator input |
| Pin 8 | RC0 — Digital I/O / SOSCO |
| Pin 9 | RC1 — Digital I/O / SOSCI |
| Pin 10 | RC2 — Digital I/O / CCP1 |
| Pin 11 | VUSB — USB internal 3.3V regulator output |
| Pin 12 | D- — USB D- line |
| Pin 13 | D+ — USB D+ line |
| Pin 14 | RC4 — Digital I/O / D-/D+ shared pins when USB disabled |
| Pin 15 | RC5 — Digital I/O / D-/D+ shared pins when USB disabled |
| Pin 16 | RC6 — Digital I/O / TX/CK |
| Pin 17 | RC7 — Digital I/O / RX/DT |
| Pin 18 | VSS — Ground (second pad) |
| Pin 19 | VDD — Positive supply |
| Pin 20 | RB0 — Digital I/O / interrupt-on-change / ECCP2 |
| Pin 21 | RB1 — Digital I/O / interrupt-on-change / ECCP2 |
| Pin 22 | RB2 — Digital I/O / interrupt-on-change |
| Pin 23 | RB3 — Digital I/O / interrupt-on-change / CCP2 |
| Pin 24 | RB4 — Digital I/O / interrupt-on-change |
| Pin 25 | RB5 — Digital I/O / interrupt-on-change / PGM |
| Pin 26 | RB6 — Digital I/O / interrupt-on-change / PGC (ICSP clock) |
| Pin 27 | RB7 — Digital I/O / interrupt-on-change / PGD (ICSP data) |
| Pin 28 | VDD — Positive supply (second pad) |
Typical Applications
PIC18F24K50T-I/ML is suitable for 6 applications: USB HID Input Devices, USB-to-UART Bridge, USB Sensor Hub / Data Logger, USB Mass Storage / MIDI Device, Consumer USB Charging Controller, Industrial USB Sensor Module.
USB HID Input Devices
The PIC18F24K50T-I/ML is purpose-built for USB HID input devices - keyboards, mice, game controllers, and custom HID peripherals - because its integrated USB 2.0 full-speed transceiver eliminates the external PHY and pull-up resistors normally required for low-speed USB. The on-chip 48 MHz oscillator is accurate enough for USB signaling without an external 12 MHz crystal, reducing BOM by 3 components. With 16 KB Flash, the Microchip USB stack consumes about 6 KB, leaving 10 KB for HID report descriptors and application logic. Typical firmware occupies under 4 KB of C code, leaving room for bootloaders or vendor-specific report formats.
Recommended
USB-to-UART Bridge
For USB-to-UART bridges (CDC class), the PIC18F24K50T-I/ML provides a single-chip solution integrating USB transceiver, UART, and 48 MHz oscillator in a 28-pin QFN that fits into USB connector dongles. The CDC firmware stack uses about 4 KB of Flash, leaving ample room for buffer management, and the 2 KB RAM is sufficient for 64-byte USB packet buffering at full-speed. Operating from 5V USB bus power directly (no regulator needed), the K50 simplifies the dongle to a single IC plus connectors, ideal for debug serial bridges and IoT provisioning tools.
Recommended
USB Sensor Hub / Data Logger
The PIC18F24K50T-I/ML serves as a USB sensor hub where it aggregates SPI or I2C sensor readings and streams them to a host PC at USB full-speed (1 MB/s effective throughput). Its 10-bit ADC with 14 channels handles analog sensors while the MSSP module interfaces digital sensors, and the 256-byte EEPROM stores calibration constants. The 2 KB RAM buffers sensor frames between USB transactions, and the nanoWatt XLP deep-sleep mode drops quiescent current below 50 nA for battery-powered field loggers that wake on timer interrupt.
Recommended
USB Mass Storage / MIDI Device
For USB mass storage devices (thumb drives with custom protocols), USB MIDI controllers, or USB audio class 1.0 peripherals, the PIC18F24K50T-I/ML provides the necessary endpoint configuration in a single IC. The 16 KB Flash holds the USB class stack plus 1-2 KB of class-specific descriptors, and the 28-pin QFN exposed pad provides adequate thermal dissipation for the 25 mA typical operating current. Designers route USB DP/DN directly to the IC pins, with a 100 nF decoupling cap on VUSB.
Recommended
Consumer USB Charging Controller
USB charging controllers that negotiate with downstream ports benefit from the PIC18F24K50T-I/ML's integrated USB transceiver. The K50 monitors D+/D- lines and toggles them to advertise BC 1.2 charging modes (SDP/CDP/DCP) under firmware control. Operating from 5V USB input, its 2.5V-5.5V range accommodates direct VBUS connection, while its compact 28-pin QFN fits into wall-wart form factors. Firmware can implement proprietary or QuickCharge handshakes via GPIO-driven protocols.
Recommended
Industrial USB Sensor Module
In industrial sensor modules with USB diagnostics, the PIC18F24K50T-I/ML's -40C to +85C industrial temperature range handles factory-floor environments, and its integrated USB eliminates external components that would otherwise compromise ingress protection. The 16 KB Flash stores USB stack plus Modbus RTU or proprietary protocol firmware, while the 2 KB RAM buffers fieldbus frames. Engineers use the MSSP for SPI sensors, the 10-bit ADC for analog inputs, and the ECCP for PWM actuator control.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F24K50T-I/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F24K50-I/ML | PIC18F24K50T-I/SS | PIC18F24K50-E/ML | PIC18F24J50T-I/ML | PIC18F24K40T-I/ML |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin QFN (ML) 6x6 mm | 28-pin QFN (ML) 6x6 mm - same | 28-pin SSOP (SS) - different footprint | 28-pin QFN (ML) 6x6 mm - same | 28-pin QFN (ML) 6x6 mm - same | 28-pin QFN (ML) 6x6 mm - same |
| Flash Program Memory | 16 KB | 16 KB | 16 KB | 16 KB | 16 KB | 16 KB |
| Data RAM | 2 KB | 2 KB | 2 KB | 2 KB | 3.7 KB | 2 KB |
| USB Module | USB 2.0 FS Device, integrated | USB 2.0 FS Device, integrated | USB 2.0 FS Device, integrated | USB 2.0 FS Device, integrated | USB 2.0 FS Device, integrated | No USB peripheral |
| Supply Voltage Range | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.0 V to 3.6 V | 2.5 V to 5.5 V |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +125C | -40C to +85C | -40C to +85C |
| Maximum CPU Frequency | 48 MHz (16 MIPS) | 48 MHz (16 MIPS) | 48 MHz (16 MIPS) | 48 MHz (16 MIPS) | 48 MHz (16 MIPS) | 64 MHz (16 MIPS) |
| Internal Oscillator | Yes, 48 MHz USB-accurate | Yes, 48 MHz USB-accurate | Yes, 48 MHz USB-accurate | Yes, 48 MHz USB-accurate | Yes, 48 MHz | Yes, 64 MHz |
| Packaging Format | Tape and Reel | Tray | Tape and Reel | Tube / Tray | Tape and Reel | Tape and Reel |
Key Differentiators
- Integrated USB 2.0 full-speed transceiver eliminates external PHY and 12 MHz crystal (vs PIC18F4550)
- 48 MHz internal oscillator is USB-spec accurate without external components (vs PIC18F24K40)
- nanoWatt XLP deep-sleep below 50 nA enables battery-powered USB designs (vs PIC18F24J50)
- Industrial -40C to +85C temperature range plus extended -40C to +125C variant (vs PIC18F24K50T-I/SS)
Design Notes
The PIC18F24K50T-I/ML's 28-pin QFN (ML 6x6 mm) package has a center exposed thermal pad that MUST be soldered to a 4 mm x 4 mm copper pad on the PCB with at least 9 thermal vias (0.3 mm drill, 0.5 mm pitch) for adequate heat dissipation. Skipping the exposed pad connection reduces thermal performance by approximately 50% and may cause I/O current-limit issues under sustained load. Additionally, place a 100 nF decoupling capacitor within 3 mm of each VDD pin and a 4.7 uF bulk capacitor on VUSB for USB transceiver stability.
Allocate at least 4 KB of the 16 KB Flash for the Microchip MLA USB stack (HID/CDC/MIDI class plus USB driver). Failing to budget USB stack overhead is the #1 reason firmware overflows the K50's Flash. Also enable the 48 MHz PLL only when USB is active; running the PLL without USB attached wastes power. Use the ICSP pins (RB6/RB7) for in-circuit programming but ensure no strong pull-ups on those lines during reset, or programming will fail.
The PIC18F24K50T-I/ML features nanoWatt XLP deep-sleep mode with currents below 50 nA typical, but peripheral leakage from floating I/O pins can dominate quiescent current in low-power designs. Tie all unused I/O pins to either VDD or VSS via firmware configuration registers (not just external pull-ups) to prevent CMOS input oscillations from drawing microamps per pin. The VUSB pin requires a 100 nF + 4.7 uF capacitor pair for the internal 3.3V LDO regulator that powers the USB transceiver.
Compliance Information
RoHS and REACH compliant per Microchip product page. Industrial -40C to +85C temperature range (not AEC-Q100 automotive qualified). Lead-free QFN package per JEDEC J-STD-020 MSL-3.
