PIC17LC43T-08/L - 8KB OTP 8-bit MCU, 33 I/O, 44-PLCC | Microchip
MPN: PIC17LC43T-08/L ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.85 | $9.85 |
| 10 | $8.92 | $89.20 |
| 100 | $7.45 | $745.00 |
| 500 | $6.3 | $3,150.00 |
| 1,000 | $5.2 | $5,200.00 |
PIC17LC43T-08/L Overview
What is an 8-bit OTP microcontroller? An 8-bit OTP microcontroller is a single-chip computer built around an 8-bit data path with non-volatile program memory that can be written exactly once after manufacture. OTP sits in the hierarchy: microcontroller -> embedded processor -> semiconductor IC. Compared with flash-based MCUs, OTP variants offer lower per-unit cost for high-volume, fixed-program applications because they omit the erase circuitry and complex charge-pump circuitry required for in-application reprogramming. The PIC17C/LC family is one of the original high-performance 8-bit PICmicro lines, predating the now-ubiquitous PIC18 and dsPIC families.
Key features include a 16-bit internal data bus for high throughput, a Harvard architecture with separate program and data paths, multiple power-saving modes, and a peripheral set including timers, a USART, and analog comparators. The wide 2.5V-5.5V operating range supports both 3.3V and 5V system designs, simplifying integration into legacy industrial and commercial boards. The 33 I/O pins are organized into multiple ports with individually programmable direction.
The PIC17LC43T-08/L executes most instructions in a single 121 ns cycle (program branches and table reads/writes take 2 cycles), giving roughly 8 MIPS throughput at 8 MHz. The 16-bit instruction width carries more information than 14-bit PIC16 opcodes, allowing richer addressing modes and a larger linear program space, which is one reason this part was historically positioned for higher-end 8-bit designs than the PIC16 mid-range family.
Typical applications include industrial control boards, appliance controllers, motor-control signal processors, security and access-control panels, and embedded sensor hubs. Its OTP memory makes it a fit for cost-sensitive, fixed-firmware products shipped in high volume, where end-user firmware updates are not required and BOM cost dominates.
When designing with this device, note that OTP memory cannot be re-programmed in-circuit after the first write; production programming fixtures or factory pre-programming is required. Also verify that any existing firmware assets are available, because many legacy PIC17C/LC code bases have been migrated to PIC18 or dsPIC33 and are no longer maintained.
This page synthesizes distributor pricing, lifecycle status, drop-in alternatives drawn from Microchip's own PIC17 family, and practical design notes not collated on any single manufacturer or distributor page.
Drop-in alternatives for PIC17LC43T-08/L — 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 PIC17LC43T-08/L (same form factor and footprint) — differing in Program Memory Size, Package, Data Bus Width, Instruction Cycle Time, Instruction Cycle.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17C43-08I/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C43T-25I/PQ
✅ Drop-In✓ In Stock
$13.5 / Unit
View Datasheet →PIC17C43T-25/PQ
✅ Drop-In✓ In Stock
$8.1 / Unit
View Datasheet →PIC17C44T-25I/PQ
✅ Drop-In✓ In Stock
$8.45 / Unit
View Datasheet →PIC17LC42AT-08/L
✅ Drop-In✓ In Stock
$5.4 / Unit
View Datasheet →PIC17C756AT-33I/L
✅ Drop-In✓ In Stock
$12.4 / Unit
View Datasheet →PIC17LC43T-08/L Maximum Ratings & Electrical Characteristics
| Device Family | PIC17LC43 |
| Architecture | 8-bit RISC, Harvard |
| Program Memory Type | OTP (One-Time-Programmable) |
| Program Memory Size | 8 KB |
| RAM Size | 454 bytes |
| Data Bus Width | 16-bit (internal) |
| Maximum Clock Speed | 8 MHz |
| Instruction Cycle | 121 ns (4 clock periods per cycle) |
| Instruction Set Size | 58 single-word instructions |
| Supply Voltage Range | 2.5 V to 5.5 V |
| Number of I/O Pins | 33 |
| Package Type | 44-pin PLCC (J-Lead) |
| Mounting Type | Surface Mount |
| Operating Temperature Range | 0C to +70C (Commercial) |
| RoHS Status | Compliant |
PIC17LC43T-08/L Pin Configuration
| Pin 1 | RA0 — PORTA bit 0 (digital I/O) |
| Pin 2 | RA1 — PORTA bit 1 (digital I/O) |
| Pin 3 | RA2 — PORTA bit 2 (digital I/O) |
| Pin 4 | RA3 — PORTA bit 3 (digital I/O) |
| Pin 5 | RA4 — PORTA bit 4 (digital I/O) |
| Pin 6 | RA5 — PORTA bit 5 (digital I/O) |
| Pin 7 | RA6 — PORTA bit 6 (digital I/O) |
| Pin 8 | RA7 — PORTA bit 7 (digital I/O) |
| Pin 9 | RB0 — PORTB bit 0 (digital I/O, external interrupt) |
| Pin 10 | RB1 — PORTB bit 1 (digital I/O, external interrupt) |
| Pin 11 | RB2 — PORTB bit 2 (digital I/O) |
| Pin 12 | RB3 — PORTB bit 3 (digital I/O) |
| Pin 13 | RB4 — PORTB bit 4 (digital I/O) |
| Pin 14 | RB5 — PORTB bit 5 (digital I/O) |
| Pin 15 | RB6 — PORTB bit 6 (digital I/O, in-circuit debug) |
| Pin 16 | RB7 — PORTB bit 7 (digital I/O, in-circuit debug) |
| Pin 17 | VDD — Positive supply voltage (2.5V-5.5V) |
| Pin 18 | VSS — Ground reference |
| Pin 19 | OSC1 — Crystal oscillator input |
| Pin 20 | OSC2 — Crystal oscillator output |
| Pin 21 | RC0 — PORTC bit 0 (digital I/O / T0CKI timer0 clock) |
| Pin 22 | RC1 — PORTC bit 1 (digital I/O / CCP2) |
| Pin 23 | RC2 — PORTC bit 2 (digital I/O / CCP1) |
| Pin 24 | RC3 — PORTC bit 3 (digital I/O) |
| Pin 25 | RC4 — PORTC bit 4 (digital I/O / SDI) |
| Pin 26 | RC5 — PORTC bit 5 (digital I/O / SDO) |
| Pin 27 | RC6 — PORTC bit 6 (digital I/O / TX) |
| Pin 28 | RC7 — PORTC bit 7 (digital I/O / RX) |
| Pin 29 | RD0 — PORTD bit 0 (digital I/O) |
| Pin 30 | RD1 — PORTD bit 1 (digital I/O) |
| Pin 31 | RD2 — PORTD bit 2 (digital I/O) |
| Pin 32 | RD3 — PORTD bit 3 (digital I/O) |
| Pin 33 | RD4 — PORTD bit 4 (digital I/O) |
| Pin 34 | MCLR — Master clear reset (active low) |
| Pin 35 | VSS — Ground reference |
| Pin 36 | NC — Not connected (per datasheet) |
| Pin 37 | NC — Not connected (per datasheet) |
| Pin 38 | NC — Not connected (per datasheet) |
| Pin 39 | T0CKI — Timer0 external clock input (shared with RA) |
| Pin 40 | INT — External interrupt input |
| Pin 41 | NC — Not connected (per datasheet) |
| Pin 42 | NC — Not connected (per datasheet) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | VDD — Positive supply voltage (2.5V-5.5V) |
Typical Applications
PIC17LC43T-08/L is suitable for 6 applications: Industrial Control Boards, Appliance Controllers, Motor Control Signal Processors, Security and Access Control Panels, Embedded Sensor Hubs, Legacy Embedded Replacement.
Industrial Control Boards
The PIC17LC43T-08/L is well-suited for industrial control boards requiring deterministic 8-bit processing, 33 I/O for switch and relay multiplexing, and 2.5V-5.5V operation that integrates directly with 5V industrial logic. Its 8.25 MIPS throughput at 8 MHz executes PID loops, debounced keypad scanning, and indicator LED multiplexing within tight control intervals. OTP memory locks the firmware against field tampering, which is important for safety-critical interlocks in factory equipment. The 44-pin PLCC package accepts standard IC sockets for serviceability on legacy factory floor controllers.
Recommended
Appliance Controllers
White-goods and small-appliance controllers benefit from the PIC17LC43T-08/L's 33 I/O for driving seven-segment displays, sensing temperature/pressure inputs, and controlling triac-fired heater or motor loads. OTP memory eliminates firmware-update pathways in cost-sensitive appliances where liability concerns outweigh service flexibility. The 121 ns instruction cycle provides deterministic response for safety interlocks and overcurrent detection. Operating from 2.5V to 5.5V simplifies designs that need to run from rectified 5V or 3.3V rails common in modern appliance power supplies.
Recommended
Motor Control Signal Processors
Brushless DC and stepper motor control loops rely on deterministic interrupt latency and fast I/O toggling, both delivered by the PIC17LC43T-08/L at 8 MHz / 121 ns instruction cycle. Its 33 I/O pins can simultaneously drive three-phase gate signals, sense Hall-effect rotor position, and run closed-loop PWM at audio-inaudible frequencies. The 16-bit internal data bus accelerates the multiply-accumulate math used in field-oriented control. OTP firmware locks calibration constants that tune motor startup behavior and prevent unauthorized parameter changes in commercial motor drives.
Recommended
Security and Access Control Panels
Access control panels require tamper-resistant firmware and reliable keypad scanning across 33 I/O, both provided by the PIC17LC43T-08/L. OTP memory prevents firmware extraction and reverse-engineering of access codes and credential algorithms, a critical security property for commercial access systems. The 8 MIPS throughput handles matrix keypad debouncing, RFID reader interfaces, and lock-driver relay control with margin. Operating from 2.5V to 5.5V supports battery-backed RTC subsystems and 5V lock-driver rails on the same PCB.
Recommended
Embedded Sensor Hubs
Multi-sensor data acquisition boards use the PIC17LC43T-08/L to read analog sensors through external ADCs, log data, and drive display or communication interfaces. The 33 I/O pins multiplex several SPI or I2C sensor buses plus UART links for telemetry output. OTP firmware locks sensor calibration coefficients that are tuned per-board at production, removing the need for external EEPROM. The wide 2.5V-5.5V supply supports battery and line-powered sensor deployments in remote monitoring stations.
Recommended
Legacy Embedded Replacement
The PIC17LC43T-08/L is the production-programmed counterpart of the windowed PIC17C43 family and is used to replace end-of-life PIC17C43 OTP/EPROM sockets in legacy products still in field service. Its pin-compatible 44-PLCC J-lead footprint matches existing PCB land patterns, eliminating the need for board respins. OTP memory at the "/L" package variant supports high-volume production runs where firmware is locked at factory programming. Engineers sustaining legacy industrial, medical, or aerospace systems rely on this part to keep decades-old equipment operational without re-architecting.
Recommended
Recommended Products Summary
Engineering reference data for PIC17LC43T-08/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17C43-08I/L | PIC17C43T-25I/PQ | PIC17C43T-25/PQ | PIC17C44T-25I/PQ | PIC17LC42AT-08/L | PIC17C756AT-33I/L |
|---|---|---|---|---|---|---|---|
| Package | 44-PLCC (J-Lead) | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same | 44-PLCC (J-Lead) - same |
| Brand | Microchip Technology | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same | Microchip Technology - same |
| Program Memory Type | OTP | Windowed EPROM | Windowed EPROM | Windowed EPROM | Windowed EPROM | OTP | Windowed EPROM |
| Program Memory Size | 8 KB | 8 KB | 8 KB | 8 KB | 16 KB | 4 KB | 16 KB |
| Max Clock Speed | 8 MHz | 8 MHz | 25 MHz | 25 MHz | 25 MHz | 8 MHz | 33 MHz |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 | 33 |
| Operating Temperature | 0C to +70C (Commercial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | NRND | NRND |
Key Differentiators
- Lower-cost OTP variant for high-volume production (vs PIC17C43-08I/L)
- Pin-compatible upgrade path to 25 MHz variants (vs PIC17C43T-25I/PQ)
- Doubled program memory in same package (vs PIC17LC42AT-08/L)
Design Notes
OTP memory can be written exactly ONCE per device. Plan production programming flow carefully: build a verified firmware image, lock the part number, and only commit to programming once final QA is complete. There is no field-reprogramming path; any firmware bug discovered after programming bricks the device. For development cycles use the windowed PIC17C43 EPROM variant (e.g., PIC17C43-08I/L) for erase-and-retry cycles.
Place a 0.1 uF ceramic decoupling capacitor as close as possible to each VDD pin (pins 17 and 44 on the 44-PLCC package) with a low-inductance ground return. Add a bulk 10 uF tantalum or aluminum electrolytic capacitor on the VDD rail near the IC. The PIC17LC43T-08/L operates from 2.5V to 5.5V; verify that VDD ramp time meets the datasheet power-on reset specification, or use an external reset supervisor for slow-ramping supplies.
Route the crystal oscillator traces (OSC1, OSC2) short and symmetric, with a ground guard ring on both sides, to minimize EMI pickup that can corrupt the internal clock. Keep high-current switching traces (relay drivers, motor phases) physically separated from the crystal area. For 44-PLCC J-lead designs, the exposed pads on the bottom of the package are not present; standard PCB land patterns with socket compatibility should be used for serviceability.
The PIC17LC43T-08/L in 44-PLCC commercial temperature grade is rated 0C to +70C junction. Estimated: at 8 MHz clock and 5.5V supply, the device draws roughly 25 mA active and 5 mA standby, dissipating approximately 0.14 W continuous. With theta_JA around 70 C/W for the PLCC package, this yields a 10C junction rise above ambient, well within the 70C commercial ceiling.
Compliance Information
RoHS and lead-free per Microchip product page; halogen-free status not explicitly stated. AEC-Q100 not applicable (commercial-grade MCU, not automotive-qualified).
