PIC18F45Q43-I/P - 8-Bit 64MHz 32KB Flash MCU 40-PDIP | Microchip
MPN: PIC18F45Q43-I/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.2 | $4.20 |
| 10 | $3.78 | $37.80 |
| 100 | $3.35 | $335.00 |
| 500 | $2.95 | $1,475.00 |
| 1,000 | $2.62 | $2,620.00 |
PIC18F45Q43-I/P Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, non-volatile program memory (Flash), peripherals, and I/O on one die, optimized for embedded control applications where deterministic behavior, low cost, and low power matter more than raw throughput. The PIC18F belongs to Microchip's PIC18 advanced 8-bit architecture family, which targets real-time control and connectivity in a wide range of consumer, industrial, and automotive subsystems. Within that hierarchy, the PIC18-Q43 sub-family (PIC18 → PIC18F → PIC18F-Q43 → PIC18F45Q43) is positioned for advanced hardware-customization designs that need DMA, CLCs, and high-resolution PWM without resorting to a 16-bit or 32-bit MCU.
Key features include 64 MHz operation from up to 64 MHz internal oscillator, six DMA channels, three 16-bit PWMs, five UART modules (one supporting LIN/DMX/DALI), two SPI/I2C peripherals, the ADCC with hardware averaging/oversampling, zero-cross detect (ZCD), a fixed voltage reference (1.024/2.048/4.096 V), Windowed Watchdog Timer (WWDT), Cyclic Redundancy Check (CRC/SCAN) module, and 36-level interrupt vectoring for low-latency response.
Typical applications include capacitive touch user interfaces, lighting controls, motor control (BLDC/PMSM via FOC), USB-to-UART bridges, industrial sensor hubs, and low-power battery-powered IoT endpoints where XLP (eXtreme Low Power) sleep current extends battery life.
Design trade-off: choose the 40-PDIP (PIC18F45Q43-I/P) for through-hole prototyping, educational breadboarding, and socketed designs; choose the 44-TQFP (PIC18F45Q43-I/PT) when moving to surface-mount production with the same die.
This page synthesizes distributor pricing, drop-in alternatives selected from Microchip's same-family portfolio and cross-brand sources, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC18F45Q43-I/P — 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 PIC18F45Q43-I/P (same form factor and footprint) — differing in ADC, Package, Core, Program Memory (Flash), PWM Channels.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F45Q43-I/PT
✅ Drop-In✓ In Stock
$1.58 / Unit
View Datasheet →PIC18F46Q43-I/P
✅ Drop-In✓ In Stock
$1.52 / Unit
View Datasheet →PIC18F45K42-I/P
✅ Drop-In✓ In Stock
$1.68 / Unit
View Datasheet →PIC18F45K22-I/P
✅ Drop-In✓ In Stock
$2.1 / Unit
View Datasheet →PIC18F4580-I/P
✅ Drop-In✓ In Stock
$5.1 / Unit
View Datasheet →PIC18F45Q43-I/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 8-bit RISC |
| Program Memory (Flash) | 32 KB (32K x 8) |
| RAM | 2 KB |
| EEPROM | 1 KB |
| Maximum CPU Frequency | 64 MHz |
| Operating Voltage Range | 1.8 V to 5.5 V |
| ADC | 12-bit ADCC with computation and CVD |
| DAC | 5-bit DAC |
| Comparators | Yes |
| PWM | 3x 16-bit dual PWMs (6 outputs) |
| DMA Controllers | 6 channels |
| UART | 5 (one supports LIN/DMX/DALI) |
| SPI | Yes |
| I2C | Yes |
| CLC (Configurable Logic Cells) | Yes |
| Zero-Cross Detect (ZCD) | Yes |
| Windowed Watchdog Timer | Yes (WWDT) |
| CRC / SCAN | Yes |
| Voltage Reference | 1.024 V / 2.048 V / 4.096 V fixed |
| XLP (eXtreme Low Power) Technology | Yes |
| Pin Count | 40 |
| Package | 40-PDIP (through-hole) |
| Operating Temperature | -40C to +85C (industrial, -I suffix) |
| RoHS Status | Compliant |
PIC18F45Q43-I/P Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) input / programming voltage |
| Pin 2 | RA0/ANO0 — PORTA bit 0 / ADC input |
| Pin 3 | RA1/ANO1 — PORTA bit 1 / ADC input |
| Pin 4 | RA2/ANO2 — PORTA bit 2 / ADC input |
| Pin 5 | RA3/ANO3 — PORTA bit 3 / ADC input |
| Pin 6 | RA4/ANO4 — PORTA bit 4 / ADC input |
| Pin 7 | RA5/ANO5 — PORTA bit 5 / ADC input |
| Pin 8 | RE0 — PORTE bit 0 |
| Pin 9 | RE1 — PORTE bit 1 |
| Pin 10 | RE2 — PORTE bit 2 |
| Pin 11 | VDD — Positive power supply |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKI — Oscillator input / external clock |
| Pin 14 | OSC2/CLKO — Oscillator output |
| Pin 15 | RC0 — PORTC bit 0 |
| Pin 16 | RC1 — PORTC bit 1 |
| Pin 17 | RC2 — PORTC bit 2 |
| Pin 18 | RC3 — PORTC bit 3 |
| Pin 19 | RD0 — PORTD bit 0 |
| Pin 20 | RD1 — PORTD bit 1 |
| Pin 21 | RD2 — PORTD bit 2 |
| Pin 22 | RD3 — PORTD bit 3 |
| Pin 23 | RC4 — PORTC bit 4 |
| Pin 24 | RC5 — PORTC bit 5 |
| Pin 25 | RC6 — PORTC bit 6 |
| Pin 26 | RC7 — PORTC bit 7 |
| Pin 27 | RD4 — PORTD bit 4 |
| Pin 28 | RD5 — PORTD bit 5 |
| Pin 29 | RD6 — PORTD bit 6 |
| Pin 30 | RD7 — PORTD bit 7 |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive power supply |
| Pin 33 | RB0/INT — PORTB bit 0 / external interrupt |
| Pin 34 | RB1 — PORTB bit 1 |
| Pin 35 | RB2 — PORTB bit 2 |
| Pin 36 | RB3 — PORTB bit 3 |
| Pin 37 | RB4 — PORTB bit 4 |
| Pin 38 | RB5 — PORTB bit 5 |
| Pin 39 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 40 | RB7/PGD — PORTB bit 7 / ICSP data |
Typical Applications
PIC18F45Q43-I/P is suitable for 6 applications: Capacitive Touch User Interface, BLDC / PMSM Motor Control, Industrial Sensor Hub & 4-20 mA Conditioning, LED Lighting & Dimming Controllers, USB-to-UART / Sensor Bridge, Low-Power Battery IoT Endpoint.
Capacitive Touch User Interface
The PIC18F45Q43-I/P's 12-bit ADCC with Computation supports Capacitive Voltage Divider (CVD) hardware techniques that automate charge/discharge cycling, averaging, and oversampling for robust proximity and touch detection across multiple keys. With up to 36 I/O pins on the 40-PDIP, designers can scan 16-24 touch electrodes without an external touch IC, reducing BOM cost. The ADCC's hardware threshold comparison delivers button-press events directly to the CPU interrupt, keeping firmware lean. Typical touch-key latency is sub-10 ms with proper guarding and shielding.
Recommended
BLDC / PMSM Motor Control
Three 16-bit dual PWM channels provide six PWM outputs with programmable dead-band and complementary pairs ideal for three-phase motor inverters at switching frequencies up to several hundred kHz. DMA channels move ADC current-sense samples into memory without CPU intervention, freeing cycles for field-oriented-control loops. The ZCD and comparators handle back-EMF zero-crossing in sensorless trapezoidal schemes, while CLCs combine peripheral events for hardware-level fault gating. Designers can implement sensored or sensorless FOC for fans, pumps, and small appliances.
Recommended
Industrial Sensor Hub & 4-20 mA Conditioning
The 12-bit ADCC handles ratiometric bridge sensors, thermocouples, and RTDs with hardware averaging for low-noise conversion in noisy industrial environments. The 5-bit DAC and 1.024/2.048/4.096 V fixed voltage reference provide excitation sources or setpoints for 4-20 mA current loops. Five UARTs enable simultaneous LIN, RS-485, and DMX/DALI connectivity for lighting and sensor-network master nodes. Industrial temperature grade (-40 C to +85 C) and the 40-PDIP package suit panel-mount and DIN-rail designs.
Recommended
LED Lighting & Dimming Controllers
The PIC18F45Q43-I/P's 16-bit PWMs deliver flicker-free dimming down to 0.1 % duty resolution, suitable for architectural and theatrical lighting. DMX512A and DALI receive from the dedicated UART simplify networked dimming drivers without extra transceivers. The ZCD module synchronizes TRIAC phase-angle dimming to mains zero-cross, while the ADCC reads analog 0-10 V dimming inputs. CLCs can mix PWM and digital gates to drive constant-current buck or boost LED driver stages.
Recommended
USB-to-UART / Sensor Bridge
Five UARTs (one LIN/DMX/DALI capable) and DMA channels let the PIC18F45Q43-I/P serve as a multi-channel sensor-to-host bridge, aggregating field-bus data without CPU bottlenecks. The 32 KB Flash holds lightweight protocol stacks (Modbus, LIN, DMX), while hardware CRC/SCAN validates payload integrity. The 40-PDIP package is ideal for breadboard prototypes and OEM evaluation kits where socketed designs ease firmware iteration.
Recommended
Low-Power Battery IoT Endpoint
XLP (eXtreme Low Power) technology on the PIC18F45Q43-I/P delivers sub-microamp sleep currents with RTC and interrupt wake from WDT, ADC, comparators, or CLC. The 1.8 V minimum supply allows single-cell alkaline or Li-coin operation spanning years of battery life. CLCs combine peripheral events to wake the CPU only on qualified sensor changes, minimizing average current. The 32 KB Flash stores MQTT-SN or BLE-beacon payloads for remote sensor nodes.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F45Q43-I/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F45Q43-I/PT | PIC18F46Q43-I/P | PIC18F45K42-I/P | PIC18F45K22-I/P | PIC18F4580-I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 40-PDIP (through-hole) | 44-TQFP (SMD, same die) | 40-PDIP - same | 40-PDIP - same | 40-PDIP - same | 40-PDIP - same |
| CPU | PIC18 8-bit, 64 MHz | PIC18 8-bit, 64 MHz | PIC18 8-bit, 64 MHz | PIC18 8-bit, 64 MHz | PIC18 8-bit, 64 MHz | PIC18 8-bit, 48 MHz |
| Flash | 32 KB | 32 KB | 64 KB | 32 KB | 32 KB | 32 KB |
| RAM | 2 KB | 2 KB | 4 KB | 2 KB | 1.5 KB | 1.5 KB |
| EEPROM | 1 KB | 1 KB | 1 KB | 1 KB | 256 B | 256 B |
| DMA Channels | 6 | 6 | 6 | 0 | 0 | 0 |
| PWM | 3x 16-bit dual (6 outputs) | 3x 16-bit dual (6 outputs) | 3x 16-bit dual (6 outputs) | 4x 10-bit PWM (8 outputs) | 2x CCP + 2x ECCP | 1x CCP + 1x ECCP |
| ADC | 12-bit ADCC w/ CVD | 12-bit ADCC w/ CVD | 12-bit ADCC w/ CVD | 12-bit ADCC w/ CVD | 10-bit ADC | 10-bit ADC |
| UART Count | 5 (1 LIN/DMX/DALI) | 5 (1 LIN/DMX/DALI) | 5 (1 LIN/DMX/DALI) | 2 | 2 | 1 + USB |
Key Differentiators
- Six DMA channels (vs PIC18F45K42-I/P)
- 16-bit PWM resolution (vs PIC18F45K22-I/P)
- Hardware ADCC with CVD (vs PIC18F4580-I/P)
- Five UARTs for multi-protocol support (vs PIC18F45K42-I/P)
Design Notes
Place a 100 nF decoupling capacitor as close as possible to each VDD/VSS pair (pins 11/12 and 31/32 on the 40-PDIP). Add a bulk 10 uF tantalum or ceramic at the board entry to suppress MCLR glitches during in-circuit serial programming. The Q43 family supports VDD from 1.8 V to 5.5 V; choose a low-Iq LDO such as MCP1700 for battery applications.
Do not leave MCLR floating; tie it to VDD through a 10 kohm resistor with a 100 nF cap to ground for noise immunity. Without proper MCLR biasing, the device may randomly enter reset during EMI events. ICSP requires RB6 (PGC) and RB7 (PGD) to remain accessible; do not populate these as outputs without isolation resistors.
Route the 64 MHz oscillator traces as short as possible and keep the crystal within 10 mm of OSC1/OSC2 to minimize EMI. For capacitive-touch CVD layouts, guard-ring the touch electrodes and add ground-fill stitching vias around the sensor pads to prevent false triggers from adjacent signal traces. The 40-PDIP package is socket-friendly for prototype flashing; reserve a 6-pin ICSP header footprint even on production boards for field updates.
Estimated: at full 64 MHz CPU activity with all peripherals active, the 40-PDIP (theta_JA around 50 C/W in still air) dissipates under 100 mW, yielding a junction temperature rise well below 5 C. No thermal management is required for typical embedded applications; however, in sealed enclosures above 60 C ambient, verify with an IR probe during worst-case firmware burn-in.
Compliance Information
RoHS and REACH compliant per Microchip product environmental compliance documentation. Industrial -40 C to +85 C temperature grade (-I suffix); not AEC-Q100 qualified for automotive - use automotive-grade PIC18F-Q43 variants for that.
