PIC18F1320-I/SO - 8KB Flash 8-bit MCU 40MHz 18-SOIC | Microchip
MPN: PIC18F1320-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.71 | $4.71 |
| 10 | $4.2 | $42.00 |
| 100 | $3.65 | $365.00 |
| 500 | $3.21 | $1,605.00 |
| 1,000 | $2.85 | $2,850.00 |
PIC18F1320-I/SO Overview
Key features include Flash program memory of 8 KB (4K x 16), 256 bytes of SRAM, 256 bytes of EEPROM, sixteen general-purpose I/O pins, a 10-bit A/D converter with seven channels, a master synchronous serial port (SSP) supporting SPI and I2C, an enhanced universal synchronous/asynchronous receiver-transmitter (EUSART), and six software-controlled nanoWatt power-managed modes that drop standby current to as low as 0.1 µA. The operating voltage spans 2.0 V to 5.5 V with a typical supply current under 1 mA at 4 MHz, and the part is specified for the industrial temperature range -40°C to +85°C.
The PIC18F1320 reaches 40 MHz maximum clock at 4.0-5.5 V with 10 MIPS throughput, while at lower voltages it operates with reduced clock speed. The 18-SOIC (Small-Outline Integrated Circuit) package offers a low-profile surface-mount footprint suitable for compact consumer and industrial layouts. The device supports in-circuit serial programming (ICSP) and in-circuit debugging via two pins, allowing field upgrades and code development without removing the part from the board.
Typical applications include low-power sensor nodes with A/D conditioning, battery-powered handheld instruments, white-goods and appliance control panels, automotive body and interior subsystems (after AEC-Q100 verification), USB/serial bridge converters, and industrial 24 V control logic (with appropriate front-end protection). The wide voltage range and nanoWatt technology make this part especially useful in energy-constrained designs that still need digital integration and mixed-signal capability.
When designing with this part, ensure all unused I/O pins are configured as outputs and tied to defined logic levels to minimize current draw in sleep modes. The A/D converter achieves its specified accuracy when the input source impedance is below 2.5 kΩ and the conversion clock period is between 0.7 µs and 25 µs; violating either limit degrades INL and DNL. Brown-out reset should be enabled in any application powered from a slowly rising rail to prevent code corruption during power transitions.
This page consolidates distributor pricing tiers, drop-in alternative parts, and practical design guidance that goes beyond the manufacturer datasheet. Engineers comparing PIC18F1320-I/SO against PIC16 family parts will find the PIC18's C-optimized instruction set, hardware multiplier, and 4-level deep interrupt stack materially simplify firmware development and real-time response.
Drop-in alternatives for PIC18F1320-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 PIC18F1320-I/SO (same form factor and footprint) — differing in Package, Core Architecture, Operating Temperature, Power-Saving Modes, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F1220-I/SO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F1320T-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$4.21 / Unit
View Datasheet →PIC18F1220-I/SS
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC18F1220-H/SS
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC18F1220-H/SO
✅ Drop-In✓ In Stock
$2.15 / Unit
View Datasheet →PIC18F1230-I/P
✅ Drop-In✓ In Stock
$3.05 / Unit
View Datasheet →PIC18F1320-I/SO Maximum Ratings & Electrical Characteristics
| Product Family | PIC18F |
| Core Architecture | PIC18 8-bit RISC (Harvard) |
| Core Size | 8-bit |
| Maximum Clock Frequency | 40 MHz |
| Program Memory (Flash) | 8 KB (4K x 16) |
| RAM | 256 bytes |
| EEPROM | 256 bytes |
| I/O Pins | 16 |
| A/D Converter | 10-bit, 7 channels |
| Supply Voltage | 2.0 V to 5.5 V |
| Operating Temperature Range | -40°C to +85°C (Industrial) |
| Package | 18-SOIC (0.295 inch / 7.5 mm width) |
| Mounting Type | Surface Mount |
| Instruction Set Architecture | RISC with C compiler-optimized core |
| Power-Saving Modes | nanoWatt Technology, 6 software-controlled modes, 0.1 µA standby |
| Communication Peripherals | EUSART, SSP (SPI / I2C) |
| Timers | Timer0, Timer1 (16-bit), Timer2, Watchdog Timer |
| In-Circuit Programmability | ICSP / ICD support |
| RoHS Status | Compliant |
PIC18F1320-I/SO Pin Configuration
| Pin 1 | RA7/OSC1/CLKI — Port A bit 7 / external clock input / crystal oscillator input |
| Pin 2 | RA6/OSC2/CLKO — Port A bit 6 / crystal oscillator output / clock output |
| Pin 3 | MCLR/VPP/RE3 — Master clear reset / programming voltage / Port E bit 3 |
| Pin 4 | RA0/AN0 — Port A bit 0 / analog channel 0 |
| Pin 5 | RA1/AN1 — Port A bit 1 / analog channel 1 |
| Pin 6 | RA2/AN2 — Port A bit 2 / analog channel 2 |
| Pin 7 | RA3/AN3/VREF+ — Port A bit 3 / analog channel 3 / ADC positive reference |
| Pin 8 | RA4/AN4/T0CKI — Port A bit 4 / analog channel 4 / Timer0 clock input |
| Pin 9 | RA5/AN5/SS/LVDIN — Port A bit 5 / analog channel 5 / SPI slave select / LVD input |
| Pin 10 | VSS — Ground reference |
| Pin 11 | VDD — Positive supply voltage (2.0 V - 5.5 V) |
| Pin 12 | RB7/KBI3/PGD — Port B bit 7 / interrupt-on-change / ICSP data |
| Pin 13 | RB6/KBI2/PGC — Port B bit 6 / interrupt-on-change / ICSP clock |
| Pin 14 | RB5/KBI1 — Port B bit 5 / interrupt-on-change |
| Pin 15 | RB4/KBI0 — Port B bit 4 / interrupt-on-change |
| Pin 16 | RB3/CCP1/AN7 — Port B bit 3 / CCP1 PWM output / analog channel 7 |
| Pin 17 | RB2/INT2 — Port B bit 2 / external interrupt 2 |
| Pin 18 | RB1/INT1/AN6 — Port B bit 1 / external interrupt 1 / analog channel 6 |
Typical Applications
PIC18F1320-I/SO is suitable for 6 applications: Battery-Powered Sensor Node, Consumer Appliance Control Panel, Industrial 24 V Control Logic, USB-to-Serial Bridge Appliance, Hobby Electronics and Robotics Hubs, Smart Lighting Control Module.
Battery-Powered Sensor Node
The PIC18F1320-I/SO suits battery-powered sensor nodes because its nanoWatt Technology drops standby current to 0.1 µA while keeping the part responsive in the 2.0-5.5 V single-cell range. The 10-bit 7-channel A/D pairs with internal sleep/wake logic so designers can duty-cycle between deep sleep and burst sampling to extend coin-cell life across years of unattended operation. A typical implementation pulls 2-4 µA averaged current when sampling temperature every 30 seconds, far lower than continuously-running MCUs.
Recommended
Consumer Appliance Control Panel
The PIC18F1320-I/SO is well-matched to white-goods and small appliance control panels that demand a small MCU with EUSART for communication, PWM timers for motor drivers, and a robust 10-bit A/D for analog keypad or thermistor inputs. The 8 KB Flash comfortably fits state-machine FSMs, fault handlers, and indicator LED patterns. Industrial -40 to +85°C rating supports harsh environments such as dishwasher motor compartments or range hoods.
Recommended
Industrial 24 V Control Logic
When treated with a regulator front-end, PIC18F1320-I/SO performs as a compact 8-bit controller for 24 V industrial logic nodes, accepting 24 V sensor inputs through opto-isolated edge conditioning and translating them to logic-level outputs. Its 40 MHz throughput handles simple protocol stack tasks and filter arithmetic, and the 18-SOIC package keeps the MCU footprint small enough for DIN-rail terminal blocks. Brown-out reset firmware idioms protect against voltage transients on long cables.
Recommended
USB-to-Serial Bridge Appliance
The PIC18F1320-I/SO can host a CDC ACM USB-to-serial bridge firmware when paired with an external USB-UART bridge such as MCP2200, exposing the EUSART pins of the MCU as a virtual COM port on the host. The 8 KB Flash accommodates USB descriptor tables plus a small command-and-control interpreter, while the 256 B of EEPROM retains user-configurable settings such as baud rate and VID/PID overrides across power cycles.
Recommended
Hobby Electronics and Robotics Hubs
Maker projects benefit from PIC18F1320-I/SO's 16 general-purpose I/O, ICSP debugging support, and exposed timer/PWM peripherals. The 18-SOIC is breadboard-friendly with an SO-to-DIP breakout board, allowing hobbyists to drive servos, read R/C inputs, and interface with sensors without external glue logic. The straightforward PIC18 architecture is widely documented in Microchip academic resources and the open-source XC8 toolchain.
Recommended
Smart Lighting Control Module
PIC18F1320-I/SO drives low-side MOSFET-based lighting controllers and PWM dimming stages using its Timer2 and capture-compare peripheral, with the 7-channel A/D reading photocells and current-sense amplifiers to implement daylight harvesting. The wide 2.0-5.5 V supply window supports single-cell battery backup as well as regulated 5 V or 3.3 V rails. Sleep modes between dim commands keep quiescent dissipation low enough for always-on applications.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F1320-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F1220-I/SO | PIC18F1320T-I/SO | PIC18F1220-I/SS | PIC18F1220-H/SS | PIC18F1220-H/SO | PIC18F1230-I/P |
|---|---|---|---|---|---|---|---|
| Package | 18-SOIC | 18-SOIC - same | 18-SOIC - same (T&R) | 20-SSOP | 20-SSOP | 18-SOIC - same | 18-PDIP (through-hole) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 8 KB | 4 KB | 8 KB | 4 KB | 4 KB | 4 KB | 4 KB |
| RAM | 256 B | 256 B | 256 B | 256 B | 256 B | 256 B | 256 B |
| Maximum Frequency | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| ADC Resolution / Channels | 10-bit / 7 ch | 10-bit / 7 ch | 10-bit / 7 ch | 10-bit / 7 ch | 10-bit / 7 ch | 10-bit / 7 ch | 10-bit / 7 ch |
| Operating 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 | 2.0 V to 5.5 V |
| Operating Temperature | -40°C to +85°C (Industrial) | -40°C to +85°C | -40°C to +85°C | -40°C to +85°C | Extended grade | Extended grade | -40°C to +85°C |
Key Differentiators
- True 18-SOIC drop-in across the PIC18F1220 family (vs PIC18F1220-I/SO)
- Identical die in tape-and-reel packaging (vs PIC18F1320T-I/SO)
- PIC18 nanoWatt Technology for sub-microwatt standby (vs PIC18F1230-I/P)
Design Notes
Estimated: at 5 V VDD, 4 MHz clock and full peripheral activity, PIC18F1320 typically draws under 2 mA total supply current. For battery-powered designs, sleep the MCU using SLPEN and idle the oscillator, then wake on INT0 / KBI / WDT interrupts. nanoWatt Technology supports 0.1 µA standby current provided all I/O pins are defined as outputs and configured to known logic states (either driven or pulled) before sleeping.
Route the ICSP PGC and PGD lines (RB6/RB7) as short, parallel traces with a ground keeper, and keep them at least 1-2 mm away from other switching edges to preserve in-circuit debug integrity. Decouple VDD with a 0.1 µF ceramic capacitor within 5 mm of the supply pin, plus a bulk 1-10 µF tantalum or electrolytic capacitor if the source impedance is high. Place MCLR/VPP decoupling (typically 10 kΩ pull-up and 0.1 µF cap to ground) adjacent to the MCLR pin to ensure clean reset behavior.
Do not enable the A/D converter with an undefined reference in ADCON1 - this can cause unpredictable channel readings; configure all analog/digital pins in PCFG<3:0> at reset. Estimate the A/D acquisition time as (Tacq = 2 µs typical + (0.05 × (Rsource + Ric) × Cx) and verify with a real bench measurement before committing to a fixed sampling sequence. Brown-out reset must be enabled for applications with slow power ramps to prevent undefined execution while VDD is below the minimum operating threshold.
The 18-SOIC package has exposed ground pin 10 and supply pin 11 only - in multiple-layer boards, place a 5 mm flooded ground plane beneath the SOIC to provide a low-impedance return path for switching I/O. For EUSART at high baud rates (above 115200), keep the RB1/RB4 traces short and use 22-33 Ω series resistors if reflections show in the eye diagram. The 10-bit ADC achieves spec accuracy only when input source impedance is below 2.5 kΩ; otherwise use an op-amp buffer to condition high-impedance sensor sources.
Compliance Information
RoHS compliant per Microchip product page; not AEC-Q100 qualified - for automotive designs use a separately AEC-Q100-validated PIC18 family member.
