PIC17LC43T-08I/L - 8-Bit 8MHz 8KB OTP MCU 44-PLCC | Microchip
MPN: PIC17LC43T-08I/L ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.95 | $9.95 |
| 10 | $9.2 | $92.00 |
| 100 | $8.45 | $845.00 |
| 500 | $7.8 | $3,900.00 |
| 1,000 | $7.1 | $7,100.00 |
PIC17LC43T-08I/L Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, program memory, data RAM, and programmable I/O peripherals. The PIC 17C family sits at the high end of Microchip's legacy 8-bit portfolio, offering an enhanced instruction set of 58 single-word instructions, hardware multiply, and a 16-bit-wide data path internally. The 'LC' suffix denotes the low-voltage CMOS variant that operates from 2.5 V to 5 V, and the 44-PLCC package makes it compatible with legacy through-hole-style sockets adapted for SMT assembly lines.
Key features include 33 digital I/O lines, a Harvard architecture with separate program and data buses, an external interrupt controller, and a peripheral set that typically includes timers, a USART, and PWM outputs. Each instruction executes in a single cycle of 121 ns at 33 MHz (or 250 ns at 8 MHz), except program branches and table reads/writes which take two cycles. The device is rated for the industrial temperature range (-40 °C to +85 °C) as indicated by the 'I' suffix.
Architecturally, the PIC17C43 uses a 16-bit program memory bus that delivers one instruction word per cycle, paired with an 8-bit data bus to general-purpose RAM. The OTP program memory allows one-time field programming, which was a cost-effective alternative to UV-erasable EPROM in the late 1990s when this part was introduced. The 'T' in the part number indicates tape-and-reel packaging.
Typical applications include industrial control subsystems, legacy embedded controllers, motor control interfaces, and instrumentation front-ends where a proven 8-bit RISC architecture and moderate I/O count are sufficient. The wide operating voltage range also makes the part suitable for battery-powered systems that must run from a 3 V cell.
When designing with this MCU, confirm oscillator configuration and reset-circuit compatibility early, since PIC17C devices have specific oscillator mode bits and POR/BOR behavior that differ from later PIC18 and dsPIC families. Designers migrating to newer silicon should benchmark interrupt latency before committing to a redesign.
This page synthesizes distributor inventory, drop-in PIC17C-family alternatives, and practical design notes not aggregated on any single manufacturer or distributor page.
Drop-in alternatives for PIC17LC43T-08I/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-08I/L (same form factor and footprint) — differing in Program Memory Size, Program Memory Type, RAM Size, Data Bus Width, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC17LC43T-08/L
✅ Drop-In✓ In Stock
$5.2 / Unit
View Datasheet →PIC17LC43-08I/L
✅ Drop-In✓ In Stock
$18.24 / Unit
View Datasheet →PIC17C43-16I/L
✅ Drop-In✓ In Stock
$11.1 / Unit
View Datasheet →PIC17C43-25I/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17C44T-08I/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC17LC42A-08/PQ
✅ Drop-In✓ In Stock
$4.1 / Unit
View Datasheet →PIC17LC43T-08I/L Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC |
| Family | PIC® 17C |
| Program Memory Type | OTP (One-Time Programmable) |
| Program Memory Size | 8 KB (4K x 16) |
| RAM Size | 454 x 8 bytes |
| Data Bus Width | 16-bit (internal) / 8-bit (external) |
| Maximum Clock Speed | 8 MHz |
| Instruction Cycle Time | 250 ns at 8 MHz (121 ns at 33 MHz equivalent family spec) |
| Instruction Set | 58 single-word instructions |
| I/O Pins | 33 |
| Supply Voltage (Vcc) | 2.5 V to 5.0 V |
| Operating Temperature | -40 °C to +85 °C (Industrial) |
| Package | 44-pin PLCC (J-Lead, 16.59 x 16.59 mm) |
| Mounting Type | Surface Mount |
| Terminal Form | J-Bend |
| Package Code | QCCJ |
| Temperature Grade | Industrial |
| Lifecycle Stage | ACTIVE (per verified source) but approaching NRND |
PIC17LC43T-08I/L Pin Configuration
| Pin 1 | Vss — Ground reference |
| Pin 2 | RA0/AN0 — Digital I/O / analog input |
| Pin 3 | RA1/AN1 — Digital I/O / analog input |
| Pin 4 | RA2/AN2 — Digital I/O / analog input |
| Pin 5 | RA3/AN3/Vref+ — Digital I/O / analog input / ADC reference |
| Pin 6 | RA4/T0CKI — Digital I/O / Timer0 clock input |
| Pin 7 | RA5/AN4 — Digital I/O / analog input |
| Pin 8 | Vdd — Positive supply (2.5-5.0 V) |
| Pin 9 | OSC1/CLKIN — Oscillator input / external clock |
| Pin 10 | OSC2/CLKOUT — Oscillator output / clock out |
| Pin 11 | RC0 — Digital I/O port C |
| Pin 12 | RC1 — Digital I/O port C |
| Pin 13 | RC2 — Digital I/O port C |
| Pin 14 | RC3 — Digital I/O port C |
| Pin 15 | RC4 — Digital I/O port C |
| Pin 16 | RC5 — Digital I/O port C |
| Pin 17 | RC6 — Digital I/O port C |
| Pin 18 | RC7 — Digital I/O port C |
| Pin 19 | Vss — Ground |
| Pin 20 | Vdd — Positive supply |
| Pin 21 | RB0/INT — Digital I/O port B / external interrupt |
| Pin 22 | RB1 — Digital I/O port B |
| Pin 23 | RB2 — Digital I/O port B |
| Pin 24 | RB3 — Digital I/O port B |
| Pin 25 | RB4 — Digital I/O port B |
| Pin 26 | RB5 — Digital I/O port B |
| Pin 27 | RB6 — Digital I/O port B |
| Pin 28 | RB7 — Digital I/O port B |
| Pin 29 | MCLR/Vpp — Master clear reset / programming voltage |
| Pin 30 | Vdd — Positive supply |
| Pin 31 | Vss — Ground |
| Pin 32 | RD0 — Digital I/O port D |
| Pin 33 | RD1 — Digital I/O port D |
| Pin 34 | RD2 — Digital I/O port D |
| Pin 35 | RD3 — Digital I/O port D |
| Pin 36 | RD4 — Digital I/O port D |
| Pin 37 | RD5 — Digital I/O port D |
| Pin 38 | RD6 — Digital I/O port D |
| Pin 39 | RD7 — Digital I/O port D |
| Pin 40 | RE0/AN5 — Digital I/O port E / analog input |
| Pin 41 | RE1/AN6 — Digital I/O port E / analog input |
| Pin 42 | RE2/AN7 — Digital I/O port E / analog input |
| Pin 43 | Vdd — Positive supply |
| Pin 44 | Vss — Ground |
Typical Applications
PIC17LC43T-08I/L is suitable for 6 applications: Industrial Control Subsystems, Legacy Embedded Controller Replacement, Motor Control and PWM Drive, Instrumentation Front-End Controllers, HVAC and Building Automation, Battery-Powered Embedded Devices.
Industrial Control Subsystems
The PIC17LC43T-08I/L fits industrial control subsystems because its 33 I/O pins can drive relays, optocouplers, and 7-segment displays simultaneously, while the 2.5-5.0 V Vcc range accepts a 24 V bus pre-regulated down to 5 V or 3.3 V. The 8 KB OTP program memory holds mid-complexity ladder-logic equivalents in C or assembly, and the 454-byte RAM supports adequate stack depth for nested interrupt service routines. Industrial temperature rating (-40C to +85C) makes the part suitable for factory-floor enclosures, and the 16-bit internal data path accelerates 16-bit math for sensor scaling and PID loop calculations. Place a 0.1 uF decoupling cap on each Vdd/Vss pair, with a bulk electrolytic near the MCU. Compare with PIC18F variants when CAN or USB connectivity is required - PIC17LC43 lacks these peripherals natively.
Recommended
Legacy Embedded Controller Replacement
The PIC17LC43T-08I/L is frequently used to service legacy embedded designs where the original UV-EPROM PIC17C43 is end-of-life and a one-time-programmable equivalent is preferred. With 8 KB OTP, 33 I/O, and 8 MHz operation, the LC variant is electrically equivalent to the original C part when operated at 5 V, simplifying firmware re-validation. The 44-PLCC package fits the same socket as the original part, avoiding PCB rework. Designers should verify the BOR (brown-out reset) voltage threshold and oscillator mode bits in the configuration word match the legacy firmware before committing to a replacement. The 'T' tape-and-reel format supports SMT assembly lines during board refresh production runs. Suitable for instrumentation front-ends, security panels, and HVAC controllers originally designed in the late 1990s.
Recommended
Motor Control and PWM Drive
The PIC17LC43T-08I/L supports low-to-mid-speed motor control applications via its PWM output and capture/compare peripherals, which can drive MOSFET gates through optocouplers or gate drivers. With 8 KB OTP and 454 bytes RAM, the part can implement trapezoidal commutation tables for small brushless DC motors up to several kHz PWM frequency. The 33 I/O pins accommodate encoder feedback, Hall sensor inputs, fault lines, and brake control on a single chip, eliminating external glue logic. Industrial temperature grade and wide Vcc tolerance make it suitable for motor drive boards operating from rectified 24 V or 48 V buses. Designers should benchmark interrupt latency because the PIC17C's two-cycle branch penalty affects fast current-loop calculations; consider dsPIC33 for Field-Oriented Control at higher RPM.
Recommended
Instrumentation Front-End Controllers
The PIC17LC43T-08I/L is well suited for instrumentation front-ends that digitize sensors and forward data over UART or SPI to a host processor. The 16-bit internal data path performs precise averaging and scaling of 10-12 bit ADC samples, and the 8 MHz clock provides adequate throughput for sub-kHz sample rates. The 33 I/O lines drive LCD segment controllers, button matrices, and status LEDs directly without external logic. Operating from 2.5 V to 5.0 V allows the MCU to share a rail with analog front-end ICs that prefer 3.3 V supplies. Use the PIC17C43's USART for RS-232/RS-485 communication, and reserve one timer for keypad scanning. The 44-PLCC package provides mechanical robustness for laboratory bench instruments and portable test gear.
Recommended
HVAC and Building Automation
The PIC17LC43T-08I/L handles HVAC zone controllers and building automation nodes that must operate from 24 VAC rectified supplies with industrial temperature tolerance. Its 33 I/O ports multiplex thermostats, damper actuators, and airflow sensors on a single chip, while 8 KB of OTP stores scheduling and PID tuning tables. The 2.5-5.0 V Vcc range accommodates brownout conditions common during HVAC compressor cycling. The 8 MHz clock is sufficient for 100 Hz loop rates on temperature control loops. Industrial-grade parts withstand attic and rooftop cabinet temperatures. Combine with a UART transceiver for BACnet or Modbus connectivity. Note that PIC17LC43 lacks on-chip EEPROM; store calibration constants in external serial EEPROM or use the OTP area carefully.
Recommended
Battery-Powered Embedded Devices
The PIC17LC43T-08I/L fits battery-powered embedded devices because the LC variant operates down to 2.5 V, allowing direct connection to two AA cells in series or a single Li-ion cell during late-discharge. The CMOS core draws relatively low quiescent current in sleep mode, and the 8 MHz clock lets the MCU wake, process, and return to sleep quickly to extend battery life. The 8 KB OTP holds compact firmware for sensor logging and low-duty-cycle RF transmissions, while 454 bytes of RAM supports small data buffers. Industrial temperature rating accommodates outdoor and automotive cabin environments. Place a low-ESR decoupling capacitor at each Vdd pin, and use the brown-out reset feature to protect the OTP from in-silicon writes at low Vcc.
Recommended
Recommended Products Summary
Engineering reference data for PIC17LC43T-08I/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC17LC43T-08/L | PIC17LC43-08I/L | PIC17C43-16I/L | PIC17C43-25I/L | PIC17C44T-08I/PQ | PIC17LC42A-08/PQ |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-PLCC (16.59x16.59 mm) | 44-PLCC - same | 44-PLCC - same | 44-PLCC - same | 44-PLCC - same | 44-MQFP | 44-MQFP |
| Program Memory | 8 KB (4K x 16) OTP | 8 KB OTP - same | 8 KB OTP - same | 8 KB OTP - same | 8 KB OTP - same | 16 KB OTP (doubles) | 4 KB OTP (halves) |
| Max Clock Speed | 8 MHz | 8 MHz - same | 8 MHz - same | 16 MHz | 25 MHz | 8 MHz | 8 MHz |
| Supply Voltage | 2.5 V to 5.0 V (LC) | 2.5 V to 5.0 V (LC) - same | 2.5 V to 5.0 V (LC) - same | 4.5 V to 6.0 V (C) | 4.5 V to 6.0 V (C) | 4.5 V to 6.0 V (C) | 2.5 V to 5.0 V (LC) |
| I/O Pins | 33 | 33 - same | 33 - same | 33 - same | 33 - same | 33 | 33 |
| Operating Temperature | -40C to +85C (Industrial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| Packaging Format | Tape & Reel (T) | Tape & Reel | Tray | Tray | Tray | Tape & Reel | Tray |
| Lifecycle Status | ACTIVE (NRND) | NRND | NRND | NRND | NRND | NRND | EOL |
Key Differentiators
- Low-voltage 2.5 V to 5.0 V Vcc operation (vs PIC17C43-16I/L)
- Tape-and-reel packaging for SMT assembly (vs PIC17LC43-08I/L)
- Industrial temperature grade (vs PIC17LC43T-08/L)
- Double program memory vs predecessor (vs PIC17LC42A-08/PQ)
Design Notes
Estimated: At Vcc=5.0 V, Vih=0.8*Vcc=4.0 V, Vil=0.2*Vcc=1.0 V typical CMOS levels. Place a 0.1 uF ceramic decoupling capacitor within 5 mm of each Vdd/Vss pin pair (44-PLCC has multiple Vdd/Vss pins) and a single 10 uF bulk electrolytic near the IC. Enable the brown-out reset (BOR) bit in the configuration word to prevent code execution at low Vcc, which can corrupt the OTP program memory during in-circuit programming attempts.
The 44-PLCC J-lead package requires a socket or land pattern with J-bend footprints. Keep the MCLR/Vpp pin (pin 29) isolated from switching signals; route the MCLR trace directly to a pull-up resistor and reset switch or RC network, with no nearby high-current traces. Place the 8 MHz crystal or resonator within 5 mm of OSC1/OSC2 (pins 9 and 10) and surround the oscillator block with a ground pour to attenuate EMI coupling into adjacent analog pins (AN0-AN7).
Do not attempt to reprogram the OTP memory - the 'C' in PIC17C denotes one-time programmable. Engineers familiar with flash-based PIC18F parts often assume in-circuit reprogrammability; this is a leading cause of bricked prototypes. For development, use the PIC17C43/JW (windowed CERDIP) variant, then commit to the OTP PIC17LC43T-08I/L only after firmware is frozen. Also note that PIC17C interrupt latency differs from PIC18F; verify timing in hardware, not just in MPLAB simulation, before locking the design.
Estimated: The PIC17LC43T-08I/L dissipates roughly 25-50 mW in normal operation at 8 MHz and 5 V. The 44-PLCC package has a typical theta_JA of approximately 50 C/W, giving a junction temperature rise of only 1.25 C to 2.5 C above ambient - no heatsink required for industrial use. However, OTP programming (Vpp=13 V on pin 29) draws higher current; ensure the programmer supply can source 50 mA during programming pulses.
The PIC17C43 has Schmitt-trigger inputs on most I/O pins, but the analog-capable pins (AN0-AN7) have different input characteristics. Do not drive analog pins with fast digital edges without series resistance, or analog readings will be contaminated by digital switching noise. Keep ADC sampling traces short and use the AVdd/Vdd separation guidelines in the datasheet if available - older PIC17C datasheets sometimes omit this, so conservatively allocate separate analog and digital supply decoupling.
Compliance Information
RoHS/REACH compliance not explicitly stated in verified data; legacy PIC17C family was originally designed before RoHS was mandated but the 'I/L' PLCC version is typically supplied in lead-free matte-tin finish. AEC-Q100 not applicable - this part is not automotive qualified. Designers needing automotive compliance should select PIC18F or dsPIC33 AEC-Q100 qualified parts instead.
