PIC18F24K40T-I/SS - 8-bit MCU, 16KB Flash, 64MHz, 28-SSOP | Microchip
MPN: PIC18F24K40T-I/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.2 | $2.20 |
| 10 | $1.98 | $19.80 |
| 100 | $1.76 | $176.00 |
| 500 | $1.54 | $770.00 |
| 1,000 | $1.32 | $1,320.00 |
| 3,000 | $1.1 | $3,300.00 |
PIC18F24K40T-I/SS Overview
The PIC18F family of microcontrollers is an 8-bit Harvard-architecture MCU line from Microchip Technology, widely used in embedded systems that require deterministic real-time control, ease of programming, and a rich peripheral set. Within the broader taxonomy, PIC18F devices are members of the 8-bit microcontroller class, which also encompasses the PIC16F and PIC12F lines, and they sit alongside 16-bit dsPIC and 32-bit PIC32 families in Microchip's MCU portfolio. The K40 sub-series specifically targets low-power (XLP) and mixed-signal applications, positioning the PIC18F24K40 between general-purpose PIC18F-K20/K22 parts and higher-pin-count PIC18F-K42/K83 devices.
Key features that distinguish the PIC18F24K40T-I/SS include its 16KB self-programmable Flash program memory with EEPROM emulation, hardware CRC and Memory Scan accelerators for functional safety, a 10-bit ADC with computation (ADC2), a 5-bit DAC for bias generation, and Core Independent Peripherals such as the Complementary Waveform Generator (CWG) and Zero-Cross Detect (ZCD). The XLP technology delivers sleep currents under 50 nA typical, while the Peripheral Pin Select (PPS) feature allows flexible signal routing on most digital I/O pins.
Typical applications include low-power sensor nodes, consumer appliance controllers, automotive body and lighting subsystems, industrial control panels, and USB-to-UART bridges where the integrated EUSART and PPS simplify BOM. The industrial temperature grade of -40C to +85C (denoted by the -I suffix) makes it suitable for outdoor enclosures and factory-floor equipment.
When designing with this part, prioritize the PPS configuration early in firmware development to lock down peripheral pin assignments before PCB layout finalization, and budget for the 5V-tolerant I/O when interfacing with legacy 5V peripherals. The device's 28-SSOP footprint is a drop-in option for the broader PIC18F24K40 and PIC18F24K22 families, simplifying PCB reuse.
Drop-in alternatives for PIC18F24K40T-I/SS — 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 PIC18F24K40T-I/SS (same form factor and footprint) — differing in ADC, Operating Temperature, Package, Core, MSL Level.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F24K40-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F24K40-E/SS
✅ Drop-In✓ In Stock
$1.45 / Unit
View Datasheet →PIC18F24K22-I/SS
✅ Drop-In✓ In Stock
$1.32 / Unit
View Datasheet →PIC18F24K20-I/SS
✅ Drop-In✓ In Stock
$1.92 / Unit
View Datasheet →PIC18F24K40T-I/SS Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit |
| Program Memory (Flash) | 16 KB (8K x 14 words) |
| RAM | 1 KB |
| EEPROM | 256 B |
| Maximum CPU Speed | 64 MHz |
| Operating Voltage Range | 2.3 V to 5.5 V |
| ADC | 10-bit ADC2 (with computation) |
| DAC | 5-bit DAC |
| Comparators | Yes (on-chip analog comparators) |
| PWM Channels | Multiple CCP/PWM outputs |
| Peripherals | CWG, HLT, WWDT, SCAN/CRC, ZCD, PPS, EUSART, SPI, I2C |
| I/O Pins | Up to 25 (on 28-pin package) |
| Package | 28-pin SSOP (5.30 mm body width) |
| Operating Temperature | -40C to +85C (industrial) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC18F24K40T-I/SS Pin Configuration
| Pin 1 | MCLR/RE3 — Master Clear (reset) input / PORTE bit 3 |
| Pin 2 | RA0 — PORTA bit 0 / analog input |
| Pin 3 | RA1 — PORTA bit 1 / analog input |
| Pin 4 | RA2 — PORTA bit 2 / analog input |
| Pin 5 | RA3 — PORTA bit 3 / analog input |
| Pin 6 | RA4 — PORTA bit 4 / analog input |
| Pin 7 | RA5 — PORTA bit 5 / analog input |
| Pin 8 | VSS — Ground reference |
| Pin 9 | RA7/OSC1 — PORTA bit 7 / oscillator input |
| Pin 10 | RA6/OSC2 — PORTA bit 6 / oscillator output |
| Pin 11 | RC0 — PORTC bit 0 |
| Pin 12 | RC1 — PORTC bit 1 |
| Pin 13 | RC2 — PORTC bit 2 |
| Pin 14 | RC3 — PORTC bit 3 / SCL |
| Pin 15 | RC4 — PORTC bit 4 / SDA |
| Pin 16 | RC5 — PORTC bit 5 |
| Pin 17 | RC6 — PORTC bit 6 / TX |
| Pin 18 | RC7 — PORTC bit 7 / RX |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply (2.3V to 5.5V) |
| Pin 21 | RB0 — PORTB bit 0 / interrupt-on-change |
| Pin 22 | RB1 — PORTB bit 1 / interrupt-on-change |
| Pin 23 | RB2 — PORTB bit 2 / interrupt-on-change |
| Pin 24 | RB3 — PORTB bit 3 / interrupt-on-change |
| Pin 25 | RB4 — PORTB bit 4 / interrupt-on-change |
| Pin 26 | RB5 — PORTB bit 5 / interrupt-on-change |
| Pin 27 | RB6 — PORTB bit 6 / ICSPCLK |
| Pin 28 | RB7 — PORTB bit 7 / ICSPDAT |
Typical Applications
PIC18F24K40T-I/SS is suitable for 6 applications: Low-Power Sensor Node, Consumer Appliance Control Panel, Automotive Body and Lighting Module, Industrial Control Panel, USB-to-UART Bridge Adapter, Smart Metering and Energy Monitor.
Low-Power Sensor Node
The PIC18F24K40T-I/SS fits low-power sensor nodes thanks to its XLP nanoWatt sleep mode, which drops quiescent current under 50 nA typical at 3V per Microchip's datasheet. The 10-bit ADC2 with computation wakes the CPU only on threshold crossings, while the CWG peripheral can drive a sensor excitation pulse without core intervention. Engineers place this part in battery-powered thermostats, environmental monitors, and remote IoT endpoints where a 3.6V lithium primary cell must last 10+ years. The 1KB RAM handles modest sensor stacks, and the 16KB Flash accommodates BLE/Sigfox protocol libraries plus over-the-air update bootloaders.
Recommended
Consumer Appliance Control Panel
In consumer appliances such as washing machines, induction cooktops, and microwave ovens, the PIC18F24K40T-I/SS drives HMI elements with its CCP/PWM outputs for LED dimming and buzzer control, while the integrated CWG generates anti-noise complementary gate-drive signals for power stages. The 5-bit DAC biases analog front-end circuits for load sensing, and the 10-bit ADC2 measures temperature, current, and line voltage at 100K samples/s aggregate throughput. Operating from 2.3V to 5.5V allows the part to share a 5V rail with triac-driver optos, simplifying isolation design.
Recommended
Automotive Body and Lighting Module
Automotive body controllers (BCM) and lighting ECUs use the PIC18F24K40T-I/SS as a local sub-controller for LED matrix drivers, door modules, and ambient lighting. The CWG peripheral can synthesize PWM at frequencies suitable for tail-light fade patterns without CPU loading, and the ZCD detects AC line zero crossings for SCR-driven incandescent backups. The industrial -40C to +85C rating covers cabin environments; engineers needing under-hood AEC-Q100 grade migrate to the Q1 variant. EUSART and SPI/I2C peripherals connect to LIN bus bridges and LED-driver ASICs.
Recommended
Industrial Control Panel
Industrial control panels for PLCs, motor drives, and process-control instrumentation use the PIC18F24K40T-I/SS for discrete I/O aggregation, pushbutton/keypad scanning, and operator-display multiplexing. The 24 I/O lines on the 28-SSOP accommodate 4x4 matrix keypads plus indicator LEDs without external I/O expanders. Hardware CRC/Scan accelerates safety checks on incoming commands, while the WWDT (Windowed Watchdog Timer) helps meet IEC 61508 SIL requirements. The -40C to +85C industrial temperature grade handles factory-floor thermal extremes, and 5V tolerance interfaces directly with legacy 5V logic in retrofit installations.
Recommended
USB-to-UART Bridge Adapter
In compact USB-to-UART debug bridges, the PIC18F24K40T-I/SS uses its on-chip EUSART to translate between a USB CDC host and a legacy RS-232/RS-485 device at rates up to several hundred kbps. The 16KB Flash accommodates small firmware stacks, while PPS routes the UART TX/RX to convenient pins for the USB connector. With an external USB-UART IC (e.g. MCP2221 or FT231X), this PIC serves as a low-cost adapter. The wide 2.3V to 5.5V supply range supports both 3.3V and 5V target devices on the UART side.
Recommended
Smart Metering and Energy Monitor
Smart electricity, water, and gas meters use the PIC18F24K40T-I/SS to sample voltage and current sensors at the 10-bit ADC2 throughput and store historical data in 1KB RAM or external EEPROM. The 5-bit DAC generates a calibration reference for analog front ends, while CWG and PWM drive low-side MOSFET switches for relay control. XLP technology keeps average current below 10uA so the meter meets 10-year battery-life targets. The on-chip EEPROM stores calibration constants, and the hardware CRC protects log integrity against tampering.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F24K40T-I/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F24K40-I/SS | PIC18F24K40-E/SS | PIC18F24K22-I/SS | PIC18F24K20-I/SS |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SSOP | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same |
| Program Memory (Flash) | 16 KB | 16 KB | 16 KB | 16 KB | 16 KB |
| RAM | 1 KB | 1 KB | 1 KB | 768 B | 768 B |
| Maximum CPU Speed | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Operating Temperature | -40C to +85C (industrial) | -40C to +85C | -40C to +125C (extended) | -40C to +85C | -40C to +85C |
| PPS (Peripheral Pin Select) | Yes | Yes | Yes | No | No |
| CWG (Complementary Waveform Generator) | Yes | Yes | Yes | No | No |
| Packaging Format | Tape & Reel | Tube | Tube | Tube | Tube |
Key Differentiators
- Core Independent Peripherals (CWG + ZCD + PPS) (vs PIC18F24K22-I/SS)
- Larger RAM (1KB vs 768B) (vs PIC18F24K22-I/SS / PIC18F24K20-I/SS)
- Extended temperature variant available in same package (vs PIC18F24K40-I/SS)
Design Notes
Estimated: at 64MHz CPU, 3.3V VDD, all peripherals active, the PIC18F24K40T-I/SS draws approximately 8-12 mA typical. For battery-powered designs, switch to HFINTOSC at 1MHz or LFINTOSC at 31kHz to reduce active current to 100-200uA, and enter Sleep mode with WDT disabled for sub-50nA standby. The PPS configuration must be saved before Sleep and re-applied on wake to maintain pin-mapped functions.
Decouple VDD (pin 20) with a 100nF ceramic capacitor placed within 3mm of the package, plus a 10uF bulk capacitor on the same rail. The SSOP package benefits from a small copper pour under the exposed body to act as a thermal relief; though the SSOP lacks an exposed pad, GND traces on the top layer help dissipate modest switching losses.
A common mistake is forgetting that PPS registers must be unlocked (PPSLOCKED bit) and re-locked after configuration; otherwise pin assignments revert at reset. Also, the MCLR pin (pin 1) requires a 10k pull-up to VDD for normal operation; leaving it floating prevents the device from starting. The ICD pins RB6/RB7 should be accessible in the PCB layout for in-circuit debugging with MPLAB Snap or PICkit.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified - the -E temperature variant does not include automotive qualification; for AEC-Q100 use Microchip's Q1 automotive part numbering scheme. Conflict minerals CMRT filed per Microchip compliance portal.
