PIC18LF1320T-I/SO - 8KB Flash 8-bit MCU, 18-SOIC | Microchip
MPN: PIC18LF1320T-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.1 | $4.10 |
| 10 | $3.72 | $37.20 |
| 100 | $3.3 | $330.00 |
| 500 | $2.95 | $1,475.00 |
| 1,000 | $2.65 | $2,650.00 |
PIC18LF1320T-I/SO Overview
A PIC18 microcontroller is an 8-bit RISC MCU belonging to the PIC18 family of microcontrollers - one of Microchip's enhanced 8-bit product lines. PIC18 MCUs occupy the performance tier above base-level PIC16 parts, sit alongside PIC24/dsPIC as the upgrade path, and are widely used for cost-sensitive embedded control with abundant peripheral integration.
Key features include seven 10-bit A/D input channels, a 16-bit timer/counter, two analog comparators, a USART module supporting RS-232/RS-485, and an internal oscillator. The device supports 100,000 typical Flash erase/write cycles and >40-year data retention, validated against industrial and consumer reliability profiles.
The LF prefix denotes the low-voltage variant of the PIC18F1320, optimized for 2.0V to 5.5V operation versus the F variant's 2.0V to 5.5V standard. Internally, an enhanced Harvard architecture with separate program and data buses, 31-level hardware stack, and instruction-pipeline allow single-cycle execution for most opcodes - giving 10 MIPS throughput at 40 MHz.
Typical applications include low-power sensor nodes, USB/RS-485 bridge firmware, sensor signal conditioning, and consumer white goods. It is also deployed in battery-powered instrumentation where nanoWatt sleep modes extend operational life. In a temperature logger, the LF's 100 nA typical standby current plus 10-bit ADC let a coin-cell operate the device for years.
When designing with this device, ensure in-circuit serial programming (ICSP) connections remain accessible; the PGD/PGC pins double as RB7/RB6 and must not be permanently pulled to ground or supply. Decoupling should follow Microchip's analog/digital separation guidelines when the A/D converter is active.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone, with cross-references verified against the Microchip parametric database.
Drop-in alternatives for PIC18LF1320T-I/SO — 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 PIC18LF1320T-I/SO (same form factor and footprint) — differing in Package, Core Architecture, Operating Temperature, MSL Level, Operating Voltage Range.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF1320-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F1320T-I/SO
✅ Drop-In✓ In Stock
$4.21 / Unit
View Datasheet →PIC18F1320T-I/SS
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF1320-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F1320-I/P
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF1320T-I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 enhanced 8-bit RISC |
| Program Memory Size | 8 KB (4K x 16) Flash |
| RAM | 256 bytes |
| EEPROM | 256 bytes |
| CPU Speed (Max) | 40 MHz (10 MIPS) |
| Supply Voltage | 2.0 V to 5.5 V |
| I/O Pins | 16 |
| A/D Converter | 10-bit, 7 channels |
| Analog Comparators | 2 |
| Timers (16-bit) | 1 |
| Timers (8-bit) | 2 |
| Communication | USART (RS-232/RS-485) |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Package | 18-SOIC (SO) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Flash Endurance | 100,000 erase/write cycles typical |
| Data Retention | >40 years |
| Internal Oscillator | Yes (8 MHz, software tunable) |
| nanoWatt Power Management | Yes |
PIC18LF1320T-I/SO Pin Configuration
| Pin 1 | RA2/AN2 — Digital I/O / Analog input channel 2 |
| Pin 2 | RA3/AN3/VREF+ — Digital I/O / Analog input channel 3 / A/D reference positive |
| Pin 3 | RA4/AN4 — Digital I/O / Analog input channel 4 |
| Pin 4 | RA5/AN5 — Digital I/O / Analog input channel 5 |
| Pin 5 | VSS — Ground reference |
| Pin 6 | OSC1/RA7 — Oscillator input / Digital I/O |
| Pin 7 | OSC2/RA6 — Oscillator output / Digital I/O |
| Pin 8 | RC0 — Digital I/O (PORTC bit 0) |
| Pin 9 | RC1 — Digital I/O (PORTC bit 1) |
| Pin 10 | RC2 — Digital I/O (PORTC bit 2) |
| Pin 11 | RC3 — Digital I/O (PORTC bit 3) |
| Pin 12 | RC4 — Digital I/O (PORTC bit 4) |
| Pin 13 | RC5 — Digital I/O (PORTC bit 5) |
| Pin 14 | RC6 — Digital I/O (PORTC bit 6) |
| Pin 15 | RC7 — Digital I/O (PORTC bit 7) |
| Pin 16 | VSS — Ground reference |
| Pin 17 | VDD — Positive supply voltage (2.0V to 5.5V) |
| Pin 18 | MCLR/VPP — Master Clear reset (active low) / programming voltage input |
Typical Applications
PIC18LF1320T-I/SO is suitable for 6 applications: Battery-Powered Sensor Node, RS-485 Sensor Bridge / Industrial Field Node, USB-to-Serial Bridge Firmware Host, Consumer White Goods User Interface, Automotive Interior Accessory Controller (Non-Safety), IoT Edge Node with nanoWatt Sleep.
Battery-Powered Sensor Node
The PIC18LF1320T-I/SO is well-suited to wireless sensor nodes drawing from coin-cell or 2x AA batteries, where its 2.0V to 5.5V supply and nanoWatt standby currents of 100 nA typical extend operational life to multi-year horizons. The 7-channel 10-bit A/D converter handles thermistor, photocell, and battery-monitor inputs without external analog front-end, and the 8 KB Flash accommodates sensor-fusion firmware plus 100,000-cycle Flash endurance supports field-updatable calibration. Compared with a discrete op-amp plus ADC design, the integrated MCU shrinks the BOM and enables sleep modes keyed on internal comparators. A typical deployment pairs the device with an SPI-connected sensor and a low-power RF module; the MCU spends most of its life in sleep, waking every few seconds to sample and transmit.
Recommended
RS-485 Sensor Bridge / Industrial Field Node
Industrial RS-485 networks benefit from the PIC18LF1320T-I/SO's on-chip USART with hardware addressing support and 16 I/O pins for digital sensor aggregation. The 10 MIPS core handles Modbus RTU framing, CRC-16 calculation, and 100 Hz polling loops in real time without software bottlenecks. The -40 C to +85 C industrial temperature grade allows deployment in factory-floor enclosures, while 256 bytes of EEPROM stores node address and calibration constants non-volatilely. Unlike pure-ASIC Modbus solutions, the PIC18 firmware adapts to evolving protocol variants and customer-specific registers without hardware respin. A typical circuit places the MCU between a MAX485 transceiver and a string of digital sensors, with the A/D converter available for analog sensor backup.
Recommended
USB-to-Serial Bridge Firmware Host
The PIC18LF1320T-I/SO serves as the protocol-translation brain in USB-to-UART bridges, where its USART pairs with an external USB-to-UART IC (MCP2200 or FT232) and its 16 I/O pins handle flow-control signals and status LEDs. The 8 KB Flash accommodates USB CDC class driver firmware, while 256 bytes RAM buffers small packet payloads with flow-control back-pressure. Operating from 3.3V or 5V supply, the device integrates easily into USB-powered dongles, and its low-power standby mode keeps idle current under 100 mA unit-cost when the USB host is suspended. Compared with native-USB MCUs, the external-transceiver architecture reduces BOM cost by 30-40% while supporting industrial isolation stacks.
Recommended
Consumer White Goods User Interface
White-goods HMIs - washing machine panels, microwave keypads, dishwasher displays - deploy the PIC18LF1320T-I/SO to scan key matrices, drive LED indicators, and run 7-segment or LCD character displays. The 16 I/O pins support 4x4 keypads plus 8-digit displays without external logic, and the 7-channel 10-bit A/D reads temperature sensors and potentiometers for user input. The -40 C to +85 C operating range supports both indoor appliances and outdoor-rated enclosures, while nanoWatt sleep modes reduce standby power below 50 mA unit-cost for energy-star compliance. The PIC18 instruction set is well-documented for non-realtime HMI firmware, and the 8 KB Flash accommodates state-machine plus diagnostics.
Recommended
Automotive Interior Accessory Controller (Non-Safety)
Although not AEC-Q100 qualified, the PIC18LF1320T-I/SO appears in non-safety automotive interior accessories such as ambient lighting controllers, seat-position memory modules, and HVAC trim controls, where its 2.0V to 5.5V supply tolerance supports direct 12V battery rail operation through local regulation. The USART interfaces to body-control modules over LIN or single-wire UART, and the 10-bit A/D reads potentiometers and thermistors for trim position sensing. The -40 C to +85 C industrial temperature grade covers cabin environments; under-hood designs require AEC-Q100 parts like PIC18F25K80. The 18-SOIC package is small enough to fit inside seat-side connector housings.
Recommended
IoT Edge Node with nanoWatt Sleep
IoT edge devices at the boundary of Wi-Fi or LoRa networks run the PIC18LF1320T-I/SO as a power-managed wake-up controller, where its nanoWatt Technology reduces sleep current below 100 nA typical - small enough to run a CR2032 coin cell for multi-year horizons. The internal 8 MHz oscillator eliminates external crystal cost and BOM complexity, and the 10-bit A/D monitors battery voltage for low-battery warning transmission. The 16 I/O pins connect to interrupt-capable sensors that wake the MCU from sleep via analog-comparator edge detection. Compared with 32-bit Cortex-M0+ alternatives, the PIC18 cut platform lists at 30-50% lower unit cost and consumes a fraction of the standby current.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF1320T-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF1320-I/SO | PIC18F1320T-I/SO | PIC18F1320T-I/SS | PIC18LF1320-I/ML | PIC18F1320-I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 18-SOIC | 18-SOIC (tube) | 18-SOIC (tape & reel) | 20-SSOP | 28-QFN | 18-PDIP |
| Program Memory | 8 KB Flash | 8 KB Flash | 8 KB Flash | 8 KB Flash | 8 KB Flash | 8 KB Flash |
| RAM | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes |
| Max CPU Speed | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) |
| Supply Voltage | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V |
| I/O Pins | 16 | 16 | 16 | 16 | 16 | 16 |
| A/D Converter | 10-bit, 7 channels | 10-bit, 7 channels | 10-bit, 7 channels | 10-bit, 7 channels | 10-bit, 7 channels | 10-bit, 7 channels |
| Operating Temperature | -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 | -40 C to +85 C |
| Unit Price (qty 1, USD) | 4.10 | 3.95 | 3.85 | 3.95 | 4.30 | 4.20 |
Key Differentiators
- Tape-and-reel packaging for high-volume automated assembly (vs PIC18LF1320-I/SO (tube version))
- LF process revision optimized for low-voltage and battery applications (vs PIC18F1320T-I/SO (standard F variant))
- 18-SOIC small-outline footprint vs. larger 28- or 40-pin PIC18 variants (vs PIC18LF2420-I/SO (28-pin SOIC))
Design Notes
The PIC18LF1320T-I/SO's nanoWatt Technology provides six software-controlled power-managed modes. Estimated: at 3.0V VDD, the sleep current is 100 nA typical with watchdog disabled, allowing CR2032 coin-cell operation for 5-7 years at 1 sample-per-minute duty cycle. To achieve these numbers, disable all peripherals before entering sleep via the peripheral-disable registers, set all I/O pins to defined logic levels (not floating), and configure the watchdog timer only when periodic wake-up is needed. The on-chip voltage regulator maintains RAM contents through sleep, so no external backup battery is required.
Place a 100 nF decoupling capacitor as close as possible to the VDD pin (pin 17), with trace length under 5 mm to suppress switching noise during A/D conversions. Estimated: the A/D converter draws 1.5 mA during a 10-bit conversion, creating a 20 ns current spike that can corrupt reference voltage if decoupling is inadequate. Use a ground plane under the MCU to provide low-inductance return paths for high-frequency switching noise. Keep analog input traces (RA0-RA5) short and routed away from digital switching lines (RC0-RC7) to minimize crosstalk into the A/D converter.
Configuration bits must be set correctly before code execution - failure to configure the oscillator mode (HS vs. INT vs. RC) and watchdog timer (WDT) can cause the device to lock up or behave erratically. Common pitfall: leaving MCLR (pin 18) floating - it must be pulled to VDD through a 10 kohm resistor for normal operation, or driven low for reset. Another pitfall: in-circuit serial programming (ICSP) requires access to RB6/PGC and RB7/PGD pins - if these are permanently pulled to ground or supply, ICSP becomes impossible, requiring high-voltage parallel programming instead.
When using the internal 8 MHz oscillator at high CPU speeds, the system's EMI profile can affect sensitive analog measurements. The PIC18LF1320T-I/SO's clock-out feature (CLKOUT) can route the system clock to an I/O pin for synchronization, but adding a 100 ohm series resistor at the clock output reduces radiated emissions. For A/D converter precision, use the internal A/D converter with a separate analog ground (AGND) connected to digital ground only at one point - the VSS pin. This star-ground topology prevents digital return currents from injecting noise into the analog reference.
Compliance Information
RoHS compliant per Microchip product page and DigiKey listing. Industrial temperature grade -40 C to +85 C. Not AEC-Q100 qualified - not suitable for automotive safety applications; use PIC18F25K80 or PIC18F46K80 for AEC-Q100 needs.