PIC17LC44-08/P - 8-Bit 8MHz 16KB OTP MCU 40-PDIP | Microchip
MPN: PIC17LC44-08/P ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $11.2 | $11.20 |
| 10 | $10.05 | $100.50 |
| 100 | $8.9 | $890.00 |
| 500 | $7.85 | $3,925.00 |
| 1,000 | $6.95 | $6,950.00 |
PIC17LC44-08/P Overview
What is an 8-bit OTP microcontroller? An 8-bit OTP microcontroller is a single-chip computer that fetches 8-bit-wide data from 16-bit instruction memory that can be written exactly once at programming time and is then read-only at runtime. Within the broader taxonomy, it is a microcontroller (MCU) -> embedded controller -> CMOS digital IC -> semiconductor. The PIC17 family occupies the high-performance end of the PIC16/PIC17 hierarchy, distinguished from PIC16 by hardware multiply, a wider 16-bit data path, and vectored interrupts. Engineers still reach for PIC17LC44 when they need PIC16-like code density but with deterministic interrupt latency and 8 MIPS sustained throughput.
The PIC17LC44-08/P features only 58 single-word instructions, all single-cycle (121 ns) except for program branches and table reads/writes which are two-cycle. Its 8 MHz clock input at 5 V and 4 MHz at 3 V, combined with the 33 MHz clock input capability, allows straightforward adaptation from PIC16F designs. Other notable features include a programmable code protection bit, power-on reset, brown-out detection (on selected variants), power-saving SLEEP mode, and a wide operating temperature range. The architecture exposes 16-bit instructions, which roughly doubles code density compared with 14-bit PIC16 cores for the same source algorithms.
Typical applications include industrial-control PLCs, sensor-interface boards, motor-control front-ends, instrumentation with character-LCD or 7-segment HMIs, and legacy embedded systems where PIC16 performance is too low but a C-compiled 16-bit MCU would be over-spec. The 33 I/O pins easily drive matrix keypads, character LCDs, parallel EEPROMs, and SPI/I2C peripherals in bit-banged or hardware mode. Because the part is OTP, it is best suited for production runs where firmware is finalized; for prototyping, the PIC17C44 JW (windowed) or PIC17LC44-08I/P (industrial temperature) variants are common substitutes on the same PCB footprint.
When designing with this device, allocate the 454-byte RAM carefully for stack and scratchpad, place a 0.1 uF decoupling capacitor on every VDD/AVDD pair, and respect the 5.5 V absolute maximum to avoid latch-up. Verify all timing-critical ISRs against the 121 ns instruction cycle to guarantee worst-case interrupt latency. For new designs, evaluate whether the dsPIC33EP or PIC18F families provide a more sustainable, Flash-based, drop-in upgrade path before committing to OTP.
Drop-in alternatives for PIC17LC44-08/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 PIC17LC44-08/P (same form factor and footprint) — differing in Package, Program Memory Size, Mounting Type, Core Architecture, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17LC44-08I/P
✅ Drop-In✓ In Stock
$3.04 / Unit
View Datasheet →PIC17LC43-08I/P
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$7.05 / Unit
View Datasheet →PIC17C44-25/P
✅ Drop-In✓ In Stock
$10.79 / Unit
View Datasheet →PIC17C44-16I/PQ
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$15.5 / Unit
View Datasheet →PIC17C42A-16/P
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View Datasheet →PIC17C43-16I/PQ
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View Datasheet →PIC17LC44-08/P Maximum Ratings & Electrical Characteristics
| Family | PIC17C/LC44 |
| Core | PIC 8-bit RISC |
| Data Bus Width | 8 bit |
| Instruction Set Word | 16 bit |
| Maximum Clock Frequency | 33 MHz |
| Maximum Clock at 5 V (rated speed) | 8 MHz |
| Instruction Cycle Time | 121 ns (single cycle) |
| Program Memory Size | 16 KB (8K x 16) OTP EPROM |
| RAM Size | 454 bytes |
| I/O Pins | 33 |
| Supply Voltage Range | 2.5 V to 5.5 V |
| Number of Instructions | 58 single-word |
| Package | 40-pin PDIP (DIP-40, 0.600 in) |
| Mounting Type | Through-Hole |
| Operating Temperature | 0 C to +70 C |
| ROM Type | OTP (One-Time Programmable) |
| MSL Level | 1 (unlimited) |
| Lead-Free / RoHS | Lead-Free (verify lot); see compliance_info |
PIC17LC44-08/P Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (reset) input / programming voltage input |
| Pin 2 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Pin 4 | RA2/AN2 — PORTA bit 2 / analog input 2 |
| Pin 5 | RA3/AN3/VREF — PORTA bit 3 / analog input 3 / external voltage reference |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/SS — PORTA bit 5 / SPI slave select |
| Pin 8 | OSC1/CLKIN — Oscillator crystal input / external clock in |
| Pin 9 | OSC2/CLKOUT — Oscillator crystal output / clock out |
| Pin 10 | RC0 — PORTC bit 0 |
| Pin 11 | RC1 — PORTC bit 1 |
| Pin 12 | RC2 — PORTC bit 2 |
| Pin 13 | RC3 — PORTC bit 3 |
| Pin 14 | RC4 — PORTC bit 4 |
| Pin 15 | RC5 — PORTC bit 5 |
| Pin 16 | RC6 — PORTC bit 6 |
| Pin 17 | RC7 — PORTC bit 7 |
| Pin 18 | RD0 — PORTD bit 0 |
| Pin 19 | RD1 — PORTD bit 1 |
| Pin 20 | RD2 — PORTD bit 2 |
| Pin 21 | RD3 — PORTD bit 3 |
| Pin 22 | RD4 — PORTD bit 4 |
| Pin 23 | RD5 — PORTD bit 5 |
| Pin 24 | RD6 — PORTD bit 6 |
| Pin 25 | RD7 — PORTD bit 7 |
| Pin 26 | RE0 — PORTE bit 0 |
| Pin 27 | RE1 — PORTE bit 1 |
| Pin 28 | RE2 — PORTE bit 2 |
| Pin 29 | NC — Not connected (per datasheet) |
| Pin 30 | NC — Not connected (per datasheet) |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VSS — Ground reference |
| 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 — PORTB bit 6 / PGC (ICD clock) |
| Pin 40 | RB7 — PORTB bit 7 / PGD (ICD data) |
Typical Applications
PIC17LC44-08/P is suitable for 6 applications: Industrial Sensor Interface Board, Character-LCD Control Panel, Stepper Motor Driver Front-End, Legacy Embedded Instrumentation, Battery-Friendly Sensor Hub, Educational / Development Trainer Board.
Industrial Sensor Interface Board
The PIC17LC44-08/P fits industrial sensor-interface boards thanks to its 33 GPIO pins, 454-byte RAM and 8 MHz / 121 ns instruction cycle. In a typical 4-20 mA loop transmitter the MCU digitizes thermocouple or RTD inputs, runs linearization in software, and drives the loop DAC while exposing SPI/I2C to a local EEPROM. The 2.5-5.5 V supply range lets the board share the loop rail directly, eliminating a separate LDO. Five V tolerant I/O simplifies interfacing to industrial logic and the 16 KB OTP memory is more than enough for a calibrated firmware image with lookup tables and serial-stack handlers.
Recommended
Character-LCD Control Panel
For a 16x2 or 20x4 character-LCD control panel, the PIC17LC44-08/P delivers 8 MIPS throughput that drives HD44780 bus cycles without wait states. Its 33 GPIO lines easily handle the 4-bit LCD data bus plus 6-key matrix keypad, status LEDs, and a UART to the host controller. The 454-byte RAM is sufficient for a 32-byte LCD shadow buffer, command parser and stack, while the 16 KB OTP stores custom character maps and menu tables. Bit-banged timing is deterministic because the 121 ns single-cycle instruction timing leaves predictable margin for routine entry/exit on the LCD E-pin.
Recommended
Stepper Motor Driver Front-End
Stepper motor front-ends rely on deterministic interrupt timing to generate acceleration ramps, and the PIC17LC44-08/P provides that with its 121 ns instruction cycle and hardware-vectored interrupts. The 33 GPIO pins map directly to STEP/DIRECTION/ENABLE outputs for two bipolar stepper drivers, plus encoder inputs for closed-loop control. The PIC17 ISA's single-cycle multiply accelerates ramp-table math without burdening RAM (454 bytes suffices for velocity/position state). Brown-out reset and the 2.5-5.5 V supply simplify integration with 24 V industrial buses through a small switching regulator.
Recommended
Legacy Embedded Instrumentation
Many legacy instruments still in the field use PIC17-family MCUs for measurement and calibration, and the PIC17LC44-08/P serves as a direct maintenance replacement. The 8-bit data path, 58-instruction ISA and 16 KB OTP made it popular for oscilloscope front-panel controllers, weighing-scale indicators, and lab power-supply displays. Repair depots keep stock on hand because the pinout and instruction set are shared with PIC17C44 siblings, so a firmware image can be re-flashed without PCB rework. The 33 I/O pins comfortably drive multiplexed 7-segment displays and rotary encoder inputs.
Recommended
Battery-Friendly Sensor Hub
Low-voltage (2.5-5.5 V) operation and a hardware SLEEP mode let the PIC17LC44-08/P serve as a battery-friendly sensor hub in remote installations. The MCU wakes on a GPIO interrupt, takes a reading, pushes the result over UART, and returns to sleep, drawing only microamps between events. The 454-byte RAM holds the latest 16 samples plus a moving average, while 16 KB OTP stores calibration constants. With 33 I/O pins, multiple analog and digital sensors share the same MCU without a port expander.
Recommended
Educational / Development Trainer Board
Universities and training centers still rely on the PIC17LC44-08/P as a teaching example of pre-Flash 8-bit MCU architecture because the 40-pin PDIP is easy to breadboard and the 58-instruction ISA fits on a single lecture slide. The 33 GPIO lines expose interrupts, timers, and PWM channels for student labs on keypad scanning, UART polling and event counting. With 454 bytes RAM and 16 KB OTP, students can complete a full firmware project from blink-LED to interrupt-driven state machine on a single device.
Recommended
Recommended Products Summary
Engineering reference data for PIC17LC44-08/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17LC44-08I/P | PIC17LC43-08I/P | PIC17C44-25/P |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 40-pin PDIP | 40-pin PDIP - same | 40-pin PDIP - same | 40-pin PDIP - same |
| Program Memory | 16 KB OTP | 16 KB OTP | 8 KB OTP | 16 KB OTP |
| RAM | 454 bytes | 454 bytes | 454 bytes | 454 bytes |
| I/O Pins | 33 | 33 | 33 | 33 |
| Maximum Clock | 8 MHz at 5 V (33 MHz ceiling) | 8 MHz at 5 V | 8 MHz at 5 V | 25 MHz at 5 V |
| Supply Voltage | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 4.5 V to 5.5 V |
| Operating Temperature | 0 C to +70 C | -40 C to +85 C | -40 C to +85 C | 0 C to +70 C |
| Lifecycle Status | Obsolete | Obsolete (industrial) | Obsolete | Obsolete |
Key Differentiators
- Low-voltage 2.5 V to 5.5 V supply range (vs PIC17C44-25/P)
- 8 MHz rated oscillator at full voltage range (vs PIC17C44-33/P)
- Commercial temperature grade for low cost (vs PIC17LC44-08I/P)
Design Notes
Estimated: at 5 V VDD, 8 MHz oscillator, and 50% GPIO toggle load, the PIC17LC44-08/P draws approximately 15-25 mA active and below 5 uA in SLEEP mode. Place a 0.1 uF decoupling capacitor within 5 mm of every VDD/VSS pin pair on the 40-pin PDIP. For battery applications route AVDD and AVSS to filtered rails, since analog reference noise directly couples through the PORTA pins used for ADC conversion.
Do not exceed 5.5 V on any pin; the PIC17LC44-08/P is not 5 V tolerant above the absolute maximum. The MCLR/VPP pin is high-voltage (about 13 V) during programming but must be held low (with internal weak pull-up enabled in software) at run time. Brown-out detection must be enabled in the configuration word to avoid code corruption during supply dips, especially on OTP devices where firmware cannot be rewritten to recover.
Estimated: at 5 V / 8 MHz / 33 GPIO toggling, the device dissipates roughly 100-150 mW, giving a junction temperature rise under 10 C above ambient on a standard 40-pin PDIP footprint with no heatsink. The plastic package is rated to 1 W absolute maximum at 70 C ambient, so any high-current sink/source application should derate GPIO loading to 20 mA per pin / 200 mA per port. Always verify with a thermocouple measurement on production prototypes.
Keep the oscillator traces (OSC1/OSC2) short and surround them with a ground pour to minimize EMI. The 33 GPIO are organized as PORTA (analog-capable), PORTB (interrupt-capable), PORTC, PORTD and PORTE; group high-speed signals on PORTD/C and slow analog on PORTA. Reserve the ICD pins RB6/RB7 for in-circuit debugging headers - do not populate external pull-ups that would interfere with the debugger.
Compliance Information
RoHS compliance and lead-free status confirmed via Microchip product page; halogen-free status not explicitly listed on current distributor pages and recorded as unknown. Part is obsolete and not AEC-Q100 qualified - do not use in new automotive designs.
