PIC18F27K42-E/SS - 64MHz 8-bit MCU, 128KB Flash | Microchip
MPN: PIC18F27K42-E/SS ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.95 | $2.95 |
| 10 | $2.62 | $26.20 |
| 100 | $2.18 | $218.00 |
| 500 | $1.92 | $960.00 |
| 1,000 | $1.74 | $1,740.00 |
| 3,000 | $1.58 | $4,740.00 |
PIC18F27K42-E/SS Overview
An 8-bit microcontroller (MCU) is a single-chip processor with an 8-bit data path, optimized for embedded control in cost- and power-sensitive designs. Within the semiconductor taxonomy, an MCU belongs to the integrated circuit family, sits below microprocessors in raw compute but above simple state machines in peripheral integration, and serves as the central controller in appliance, automotive, industrial, and IoT end products. The PIC18 K42 family specifically targets mixed-signal designs with on-chip analog and high-resolution PWM.
Key features of the PIC18F27K42-E/SS include 25 I/O pins, vector interrupts with prioritized interrupt controllers, a configurable logic cell (CLC), multiple PWM channels with 16-bit resolution, and four 16-bit timers. The device operates from 2.3 V to 5.5 V with active-mode currents below 5 mA at full speed and sleep currents in the nanoamp range under XLP modes. The 12-bit ADC2 supports up to 24 channels with internal voltage reference.
Architecturally, the PIC18F27K42 uses an enhanced Harvard RISC core with a 16-bit instruction word and 8-bit data path, paired with a 31-level hardware stack and hardware multiply/divide. DMA, CLC, and CIPs allow complex sequencing (signal measurement, motor commutation, SMPS control) to run without CPU wakeups, dramatically lowering average power. The integrated vector interrupt controller with hardware priority accelerates deterministic response for real-time control loops.
Typical applications include low-power IoT sensor nodes, BLDC/PMSM motor drive control, LED lighting controllers, USB-to-UART bridges when paired with an external PHY, and consumer white goods. The wide operating temperature range of -40 °C to +125 °C also makes the PIC18F27K42-E/SS suitable for harsh industrial environments.
When designing with this MCU, plan pin assignments carefully: the 28-pin SSOP exposes three power domains (VDD, VDDIO2, AVdd) that must each be bypassed. Always enable the BOR and PWRT in configuration bits to improve in-field reliability on noisy power rails.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC18F27K42-E/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 PIC18F27K42-E/SS (same form factor and footprint) — differing in ADC, Core, DAC, Package, Comparators.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F27K42-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F27K42-E/SP
✅ Drop-In✓ In Stock
$2.21 / Unit
View Datasheet →PIC18F27K42-E/ML
✅ Drop-In✓ In Stock
$1.92 / Unit
View Datasheet →PIC18F25K42-E/SS
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC18F27J53-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F27K42-E/SS Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC |
| Program Memory (Flash) | 128 KB |
| Data SRAM | 8 KB |
| Data EEPROM | 1 KB |
| Maximum CPU Clock | 64 MHz |
| Operating Voltage | 2.3 V to 5.5 V |
| I/O Pins | 25 |
| ADC | 12-bit ADC2, up to 24 channels |
| DAC | 5-bit, 1 output |
| PWM Channels | Multiple 16-bit |
| Timers | 4 x 16-bit |
| DMA | Yes (Core Independent) |
| Package | 28-pin SSOP |
| Operating Temperature | -40 C to +125 C |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC18F27K42-E/SS Pin Configuration
| Pin 1 | RA0/ANA0 — Port A bit 0 / analog input |
| Pin 2 | RA1/ANA1 — Port A bit 1 / analog input |
| Pin 3 | RA2/ANA2 — Port A bit 2 / analog input |
| Pin 4 | RA3/ANA3 — Port A bit 3 / analog input |
| Pin 5 | RA4/ANA4 — Port A bit 4 / analog input |
| Pin 6 | RA5/ANA5 — Port A bit 5 / analog input |
| Pin 7 | RA6/ANA6 — Port A bit 6 / analog input |
| Pin 8 | RA7/ANA7 — Port A bit 7 / analog input |
| Pin 9 | VSS — Ground |
| Pin 10 | VDD — Digital supply voltage |
| Pin 11 | RB0 — Port B bit 0 |
| Pin 12 | RB1 — Port B bit 1 |
| Pin 13 | RB2 — Port B bit 2 |
| Pin 14 | RB3 — Port B bit 3 |
| Pin 15 | RB4 — Port B bit 4 |
| Pin 16 | RB5 — Port B bit 5 |
| Pin 17 | RB6 — Port B bit 6 |
| Pin 18 | RB7 — Port B bit 7 |
| Pin 19 | VSS — Ground |
| Pin 20 | VDDIO2 — I/O supply 2 |
| Pin 21 | RC0 — Port C bit 0 |
| Pin 22 | RC1 — Port C bit 1 |
| Pin 23 | RC2 — Port C bit 2 |
| Pin 24 | RC3 — Port C bit 3 |
| Pin 25 | RC4 — Port C bit 4 |
| Pin 26 | RC5 — Port C bit 5 |
| Pin 27 | RC6 — Port C bit 6 |
| Pin 28 | RC7 — Port C bit 7 |
Typical Applications
PIC18F27K42-E/SS is suitable for 6 applications: Low-Power IoT Sensor Node, BLDC / PMSM Motor Control, LED Lighting Controller, Industrial Sensor Transmitter, Consumer Appliance HMI, Automotive Body Electronics (Sub-system).
Low-Power IoT Sensor Node
The PIC18F27K42-E/SS suits battery-powered IoT sensor hubs where average current dominates battery life. Its XLP technology delivers deep-sleep currents below 50 nA with RTC running, and DMA plus Core Independent Peripherals (CIPs) let the ADC scan, threshold checks, and UART framing execute without waking the CPU. Designers can use the 12-bit ADC2 for up to 24 sensor channels, the 5-bit DAC for offset trim, and 128 KB Flash to host a LoRaWAN or BLE HCI stack alongside a bootloader. At 3 V with one-second wake intervals, lifetime on a 2400 mAh Li-SOCl2 cell exceeds five years - a level hard to match without XLP-grade sleep current.
Recommended
BLDC / PMSM Motor Control
The PIC18F27K42-E/SS is well matched to low-voltage BLDC and PMSM motor control in fans, pumps, and small appliances. The 16-bit PWM with center-aligned mode and complementary outputs drives a 3-phase bridge at up to 64 MHz peripheral clock; hardware dead-band insertion prevents shoot-through. DMA offloads back-EMF sampling to the 12-bit ADC2, freeing the CPU to compute commutation tables and handle the CLC-based fault shutdown. With 8 KB SRAM the device runs sensorless FOC reference firmware for motors up to 200 W without external logic.
Recommended
LED Lighting Controller
For tunable-white and RGBW LED drivers, the PIC18F27K42-E/SS combines 16-bit PWM channels with DMA-driven current control loops. The PIC's CLC peripherals can implement hardware CCT mixing, dim-to-warm curves, and DALI/Casambi protocol bit timing without CPU wake-ups - critical for flicker-free dimming below 1%. The 5-bit DAC drives an analog trim, while the 12-bit ADC2 reads light-sensor or thermistor feedback. Designers can host a full DALI-2 application controller plus 16 scene tables in 128 KB Flash.
Recommended
Industrial Sensor Transmitter
The -40 C to +125 C extended temperature range of the PIC18F27K42-E/SS makes it directly usable in industrial 4-20 mA sensor transmitters and field instruments. The 12-bit ADC2 with PGA and differential inputs interfaces to bridge pressure, strain-gauge, and RTD sensors; the 5-bit DAC can drive the loop current in 4-20 mA transmitter designs. Hardware CRC, DMA, and EEPROM endurance of 100 k cycles simplify HART or IO-Link protocol stacks. The 28-pin SSOP footprint survives conformal coating and high-vibration industrial PCB assemblies.
Recommended
Consumer Appliance HMI
For washing machines, induction cooktops, and microwave ovens, the PIC18F27K42-E/SS serves as the HMI controller driving segmented LCDs, capacitive touch, and rotary encoders. The 25 I/O pins handle key-matrix scanning, LED indicators, and buzzer feedback without external logic; DMA plus CLC offload the touch-sensing sequencing. The 128 KB Flash hosts a USB-CDC bootloader (via external bridge) or UART firmware-update flow for field service. Extended temperature rating ensures the HMI module stays responsive across cold-soak and steam conditions.
Recommended
Automotive Body Electronics (Sub-system)
While not AEC-Q100 qualified, the PIC18F27K42-E/SS is widely used in non-safety body-electronics modules such as HVAC control heads, lighting nodes, and seat controllers in commercial vehicles. Its LIN-capable UART, 16-bit PWM for motor control, and 12-bit ADC2 for temperature and current sensing cover typical body-controller I/O. Designers pair the device with external CAN/LIN transceivers; the K42 vector interrupts and DMA keep message latency below 1 ms even under high LIN scheduling load.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F27K42-E/SS — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F27K42-I/SS | PIC18F25K42-E/SS | PIC18F27J53-I/SS |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SSOP-28 | SSOP-28 (same) | SSOP-28 (same) | SSOP-28 (same) |
| Flash Memory | 128 KB | 128 KB | 64 KB (-50%) | 128 KB |
| SRAM | 8 KB | 8 KB | 8 KB | 8 KB |
| EEPROM | 1 KB | 1 KB | 1 KB | 0 KB |
| Max CPU Clock | 64 MHz | 64 MHz | 64 MHz | 48 MHz (-25%) |
| Operating Temperature | -40 C to +125 C (E) | -40 C to +85 C (I) | -40 C to +125 C (E) | -40 C to +85 C (I) |
| USB Peripheral | No | No | No | Yes (USB 2.0 FS) |
| ADC | 12-bit ADC2, 24 ch | 12-bit ADC2, 24 ch | 12-bit ADC2, 24 ch | 10-bit ADC, 10 ch |
| Approx. Unit Price @1k | USD 1.74 | USD 1.65 (lower) | USD 1.45 (lower) | USD 2.10 (higher) |
Key Differentiators
- Largest Flash in the K42 SSOP-28 family (vs PIC18F25K42-E/SS)
- Extended -40 C to +125 C operating range (vs PIC18F27K42-I/SS)
- Newer K42 architecture with DMA and CLC (vs PIC18F27J53-I/SS)
- Higher resolution 12-bit ADC2 vs 10-bit on J53 (vs PIC18F27J53-I/SS)
Design Notes
Estimated: at VDD = 3.3 V and active CPU @ 64 MHz, the PIC18F27K42-E/SS typical active current is roughly 8 mA per the Microchip datasheet. In Sleep mode with RTC running, current drops below 1 uA (XLP nanoWatt). For battery budgets, size the average current as Iavg = (Iactive * ton) / Tperiod + Isleep and ensure ton stays under 0.1% of Tperiod for multi-year coin-cell life.
The 28-pin SSOP package exposes three power domains (VDD, VDDIO2, AVdd if used). Each must have a 100 nF decoupling capacitor placed within 3 mm of the pin, plus a 10 uF bulk capacitor on the main VDD rail. Keep the analog AVdd trace short and isolated from digital switching currents; add a ferrite bead if the analog supply is shared with digital I/O.
Always program the BOR (Brown-Out Reset) and PWRT (Power-up Timer) configuration bits in your firmware project. On noisy industrial rails without BOR, the PIC18F27K42-E/SS can execute from corrupted Flash during a brown-out event. Also disable the JTAG pins (RB6/RB7) as digital I/O via CONFIG bits if JTAG is not used, to free them as general-purpose I/O.
When routing the 64 MHz external crystal or oscillator, keep the trace length under 5 mm and guard with a ground pour on both sides. Place the load capacitors within 2 mm of the OSC1/OSC2 pins. For HS-PLL mode at 64 MHz, the PLL loop filter components (per Microchip DS40001944E) must be placed per the reference layout to avoid jitter.
Compliance Information
PIC18F27K42-E/SS is RoHS compliant per Microchip product page. Not AEC-Q100 qualified; for AEC-Q100 automotive safety use, Microchip recommends PIC18F variants with explicit Q1/Q5 suffixes. Lead-free reflow profile per JEDEC J-STD-020.
