PIC18LC601T-I/L - 25 MHz ROMless 8-bit MCU, 68-PLCC | Microchip
MPN: PIC18LC601T-I/L ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $12.5 | $12.50 |
| 10 | $11.2 | $112.00 |
| 100 | $9.85 | $985.00 |
| 500 | $8.4 | $4,200.00 |
| 1,000 | $7.1 | $7,100.00 |
PIC18LC601T-I/L Overview
An MCU (microcontroller) is a single-chip processor core plus peripherals (RAM, Flash/ROM, I/O, timers, communication blocks) intended for embedded control. ROMless variants like the PIC18LC601T-I/L omit on-chip program memory and instead fetch code from external EPROM, Flash, or SRAM through an external memory bus, which lets designers choose memory size and update field via memory tuning rather than re-spinning the silicon. The PIC18 family is Microchip's high-performance 8-bit line, positioned above the PIC16 in instruction-set richness and peripheral count.
Key features include a Harvard RISC architecture with C-compiler optimized instruction set, 25 MHz maximum clock (10 MIPS typical), 8 x 8 hardware multiplier, 16-bit instructions with 8-bit data path, and an industrial -40 °C to +85 °C operating range. The 68-pin PLCC package supports surface-mount assembly with a J-lead footprint suitable for socketed programming and field replacement.
Typical applications include industrial control boards requiring external boot Flash, legacy PIC18 firmware migration, evaluation platforms, and motor-control daughter-cards where the host supplies program memory. Because the device is ROMless, it is commonly used as a system-on-module companion or as a controller in development kits where firmware is loaded from external memory.
When designing with this part, ensure the external memory bus timing matches the chosen program-memory device and that the oscillator is specified as an external source. For new designs consider PIC18F flash-based replacements that integrate program memory on-die and remove the external bus complexity.
This page synthesizes distributor pricing, parametric data, drop-in PIC18 same-family alternatives, and practical design notes that are not consolidated in the manufacturer datasheet.
Drop-in alternatives for PIC18LC601T-I/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 PIC18LC601T-I/L (same form factor and footprint) — differing in Instruction Set, Mounting Type, Operating Temperature, Packaging, RAM Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LC601-I/L
✅ Drop-In✓ In Stock
$6.75 / Unit
View Datasheet →PIC18C601-I/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18C601T-I/L
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LC601T-I/L Maximum Ratings & Electrical Characteristics
| Core | PIC18 (8-bit RISC, Harvard) |
| Program Memory Type | ROMless (external memory bus) |
| RAM Size | 1.5K x 8 (1536 bytes) |
| Number of I/O Pins | 26 |
| Maximum Clock Frequency | 25 MHz |
| Supply Voltage | 2.5 V to 5.5 V |
| Operating Temperature | -40 °C to +85 °C (Industrial) |
| Oscillator Type | External |
| Package / Case | 68-LCC (J-Lead), PLCC-68 |
| Mounting Type | Surface Mount |
| Instruction Set | 16-bit instructions, 8-bit data path |
| Linear Program Addressing | Up to 2 Mbytes (external) |
| Linear Data Addressing | Up to 4 Kbytes |
| Multiplier | 8 x 8 hardware multiplier |
| Packaging | Tape & Reel (TR) |
PIC18LC601T-I/L 68-lcc (j-lead), plcc-68 Pin Configuration Guide
Pin configuration for PIC18LC601T-I/L (68-lcc (j-lead), plcc-68 package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for PIC18LC601T-I/L.
Refer to the datasheet for full pin configuration.
Typical Applications
PIC18LC601T-I/L is suitable for 6 applications: Legacy Industrial Control Boards, Development Kits and Evaluation Platforms, Motor Control Daughter Cards, Embedded System-on-Module Companions, Automotive Body Electronics (Legacy), Medical Monitoring Peripherals (Legacy).
Legacy Industrial Control Boards
The PIC18LC601T-I/L's external memory bus and 68-pin PLCC socketable package make it well suited for legacy industrial control boards where existing firmware lives in external EPROM. The 25 MHz clock speed and 26 I/O pins are sufficient for PLC-style digital I/O scanning, sensor multiplexing, and relay control. Compared to flash-only PIC18F replacements, the LC601T's external bus allows swapping program memory without changing the silicon, which simplifies field updates. Designers should add a watchdog timer supervisor and ensure MCLR is properly decoupled.
Recommended
Development Kits and Evaluation Platforms
The PIC18LC601T-I/L is commonly used in PIC18 family development kits where the external memory bus is wired to a socket accepting EPROM/Flash daughter-cards. Its 25 MHz speed and 1.5 KB RAM allow real-time code execution and debugging. The 68-PLCC package is socket-friendly, enabling rapid firmware swap during bring-up. For new designs, the PIC18F8720-E/PT flash variant eliminates the external bus and is recommended unless a specific legacy toolchain requires ROMless operation.
Recommended
Motor Control Daughter Cards
With 26 I/O pins and PIC18 timer/capture peripherals, the PIC18LC601T-I/L serves as a controller on motor-control daughter-cards, generating PWM for H-bridge drivers and reading encoder feedback via QEI inputs. The 2.5-5.5 V supply is compatible with 3.3 V and 5 V logic levels. The ROMless architecture lets the host CPU upload motor-control firmware at boot. Consider PIC18F46K22-I/P for new designs - same PIC18 architecture but with on-chip flash.
Recommended
Embedded System-on-Module Companions
The PIC18LC601T-I/L acts as a peripheral companion to larger host processors, providing 26 I/O expansion and real-time interrupt handling while the host supplies program memory. The 1.5 KB RAM is sufficient for buffering sensor data. For new designs, integrate a PIC18F46K22-I/PT on the same board, eliminating the external bus overhead. Designers must verify the host-to-PIC18 SPI/I2C bus timing matches the LC601's 25 MHz clock.
Recommended
Automotive Body Electronics (Legacy)
Although the PIC18LC601T-I/L is not AEC-Q100 qualified, it has been used in non-safety automotive body modules where its -40 to +85 °C industrial temperature range, 26 I/O pins, and external memory bus supported distributed ECU architectures. The 2.5-5.5 V supply survives crank-to-run transients. For new automotive designs use AEC-Q100 qualified PIC18F66K90-I/PT or PIC18F67K22-I/PT flash variants.
Recommended
Medical Monitoring Peripherals (Legacy)
The PIC18LC601T-I/L's deterministic PIC18 instruction set and interrupt latency make it suitable for medical monitoring peripherals where consistent response time is required. The 1.5 KB RAM buffers sensor samples; the external memory bus loads application firmware from validated EPROM. For new medical designs requiring IEC 60601 compliance, choose PIC18F46K22-I/P flash-based with on-chip secure boot. Always perform full validation per IEC 62304 lifecycle requirements.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LC601T-I/L — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LC601-I/L | PIC18C601-I/L | PIC18C601T-I/L | PIC18F8720-E/PT | PIC18F8722T-I/PT |
|---|---|---|---|---|---|---|
| Package | 68-LCC (J-Lead) PLCC | 68-LCC (J-Lead) - same | 68-LCC (J-Lead) - same | 68-LCC (J-Lead) - same | 64-TQFP - differs | 64-TQFP - differs |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core | PIC18 8-bit RISC | PIC18 8-bit RISC | PIC18 8-bit RISC | PIC18 8-bit RISC | PIC18 8-bit RISC | PIC18 8-bit RISC |
| Program Memory Type | ROMless (external bus) | ROMless (external bus) | OTP EPROM | OTP EPROM | Flash (128 KB) | Flash (128 KB) |
| RAM Size | 1.5K x 8 (1536 B) | 1.5K x 8 | 1.5K x 8 | 1.5K x 8 | 3.8K x 8 | 3.8K x 8 |
| Maximum Clock Frequency | 25 MHz (LC derated) | 25 MHz | 40 MHz | 40 MHz | 25 MHz (E = extended temp) | 40 MHz |
| Supply Voltage | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V |
| I/O Pins | 26 | 26 | 26 | 26 | 70 | 70 |
| Operating Temperature | -40 °C to +85 °C (I) | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +125 °C (E) | -40 °C to +85 °C |
Key Differentiators
- Socket-friendly PLCC package for field replacement (vs PIC18F8722T-I/PT (64-TQFP))
- External memory bus allows runtime program-memory updates (vs PIC18F8720-E/PT (flash-based))
- Industrial -40 to +85 °C temperature range with 2.5-5.5 V supply (vs PIC18C601-I/L (OTP, 4.2-5.5 V only))
Design Notes
Estimated: The PIC18LC601T-I/L has no on-chip program memory. Forgetting to wire the external memory bus (PORTD/PORTE/PORTE/PORTF/PORTG) to an EPROM/Flash will leave the device unable to boot. Always confirm the program-memory device timing matches the PIC18 external bus timing diagrams in the datasheet. Verify MCLR is pulled high through a 10 kΩ resistor with a 100 nF decoupling cap to ground.
Place a 100 nF ceramic decoupling capacitor as close as possible to each VDD/VSS pair on the PIC18LC601T-I/L. The 68-PLCC has multiple VDD/VSS pins; bypassing each pair suppresses switching noise from the 25 MHz core. Add a bulk 10 µF tantalum or ceramic cap on the main supply rail. The LC variant runs at 2.5-5.5 V - operation below 2.5 V is undefined.
For the 68-PLCC footprint, follow JEDEC MO-047 land pattern with J-lead pads. Verify socket height if the device is socketed for field replacement - mismatched socket profiles cause cracked solder joints. Keep external memory bus traces short (<50 mm) and matched in length to avoid timing violations on the multiplexed address/data bus.
The PIC18LC601T-I/L is marked obsolete on verified distributor channels, with limited stock. For new designs, choose PIC18F8720-E/PT or PIC18F8722T-I/PT - same PIC18 core with on-chip flash eliminating the external memory bus. If the LC601T must be used in production, qualify a second source and validate against counterfeit detection (lot date code, decapsulation, electrical test).
Compliance Information
RoHS, REACH, lead-free, halogen-free, and conflict-minerals status not explicitly stated in verified web data; [DATA_NEEDED] markers used in specs. The part is not AEC-Q100 qualified - choose PIC18F67K22-I/PT for automotive applications.
