PIC16LC64A-04I/P - 8-Bit 4MHz 3.5KB OTP MCU 40-PDIP | Microchip
MPN: PIC16LC64A-04I/P β End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.2 | $8.20 |
| 10 | $7.38 | $73.80 |
| 100 | $6.56 | $656.00 |
| 500 | $5.85 | $2,925.00 |
| 1,000 | $5.2 | $5,200.00 |
PIC16LC64A-04I/P Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, memory (program + RAM), and peripheral interfaces onto one die. MCUs sit at the lowest tier of embedded compute - below microprocessors (which need external memory) and embedded SoCs - and dominate applications where deterministic real-time control, low power, and low cost matter more than raw throughput. The PIC16C family uses a Harvard RISC architecture with a fixed 14-bit instruction word, only 35 single-word instructions, and single-cycle execution (program branches take two cycles), giving a 4 MHz oscillator up to 1 MIPS of predictable throughput.
Key features of the PIC16LC64A-04I/P include 128 bytes of RAM, an integrated analog comparator, a Watchdog Timer with on-chip RC oscillator, power-saving Sleep mode, in-circuit serial programming capability via two pins, and a programmable code-protection mechanism. The OTP program memory allows one-time field programming, making the part suited for production volumes where firmware is stable and flash reprogrammability is not required.
Architecturally, the device uses an enhanced PIC16C6X core with separate program and data buses, a 13-bit program counter capable of addressing 8K x 14 of program space, and a file-register architecture of 128 x 8 general-purpose RAM plus special-function registers. The 22 I/O pins are arranged in ports A (6), B (8), C (8) for digital I/O, with several pins multiplexed to peripherals such as the USART (SCI/SPI), timers, and the analog comparator.
Typical applications include low-cost industrial control subsystems, appliance controllers, automotive body electronics (non-safety), sensor signal conditioning front-ends, and legacy embedded products still in service. Its wide 3.0V to 5.5V operating range, low-power consumption (15 uA typical at 5V/4 MHz, 1 uA typical at 3V/32 kHz), and OTP memory make it well-suited for sealed, high-volume, cost-sensitive designs.
A primary design consideration when using OTP is that firmware bugs cannot be patched in the field. Engineers should prototype on a windowed CERDIP variant (PIC16C64A-04I/P) or a Flash sibling (PIC16F64A family) before committing to OTP for production.
This page synthesizes distributor pricing, OTP vs Flash sibling variants, and design considerations for the PIC16LC64A-04I/P beyond the manufacturer datasheet.
Drop-in alternatives for PIC16LC64A-04I/P β 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 PIC16LC64A-04I/P (same form factor and footprint) β differing in Mounting Type, Program Memory Type, Timers, I/O Pins, Program Memory Size.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16F74A-I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16F77A-I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16C64A-04I/P
β Drop-Inβ In Stock
$6.1 / Unit
View Datasheet βPIC16LC64A-04/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16F737-I/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16LC64A-04I/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16C 8-bit RISC (Harvard) |
| Program Memory Type | OTP (One-Time Programmable) EPROM |
| Program Memory Size | 3.5 KB (2K x 14) |
| RAM Size | 128 bytes |
| Data EEPROM | 0 bytes (not present on this OTP variant) |
| Maximum Clock Frequency | 4 MHz |
| Instruction Set Size | 35 single-word instructions |
| Instruction Word Width | 14 bits |
| Execution Time per Instruction | 1 cycle (program branches: 2 cycles) |
| Supply Voltage Range | 3.0 V to 5.5 V |
| I/O Pins | 22 |
| Timers | Timer0, Timer1, Timer2 |
| Communication Peripherals | USART (SCI/SPI), SSP |
| Analog Peripherals | 1 analog comparator |
| Operating Temperature Range | -40 C to +85 C (Industrial) |
| Package Type | 40-pin PDIP (Plastic DIP, 0.600 inch / 15.24 mm width) |
| Mounting Type | Through-Hole (THT) |
| Pin Count | 40 |
| Power-Saving Modes | Sleep mode with Wake-up on pin change / WDT |
| Watchdog Timer | Yes, with on-chip RC oscillator |
| In-Circuit Programming | ICSP via RB6/RB7 |
| Code Protection | Programmable code-protection bit |
| Typical Current @ 5V, 4 MHz | 15 uA (per datasheet) |
| Typical Current @ 3V, 32 kHz | 1 uA (per datasheet) |
PIC16LC64A-04I/P Pin Configuration
| Pin 1 | /MCLR β Master Clear (reset) input, programming voltage input |
| Pin 2 | RA0 β PORTA bit 0 / analog comparator input |
| Pin 3 | RA1 β PORTA bit 1 / analog comparator input |
| Pin 4 | RA2 β PORTA bit 2 / analog comparator output |
| Pin 5 | RA3 β PORTA bit 3 / analog comparator input |
| Pin 6 | RA4 β PORTA bit 4 / Timer0 clock input (open-drain) |
| Pin 7 | RA5 β PORTA bit 5 / SS pin for SSP module |
| Pin 8 | OSC1 β Crystal oscillator input / external clock input |
| Pin 9 | OSC2 β Crystal oscillator output |
| Pin 10 | RC0 β PORTC bit 0 / Timer1 oscillator input |
| Pin 11 | VDD β Positive supply voltage |
| Pin 12 | VSS β Ground reference |
| Pin 13 | RC1 β PORTC bit 1 / Timer1 oscillator output |
| Pin 14 | RC2 β PORTC bit 2 / CCP1 output |
| Pin 15 | RC3 β PORTC bit 3 / SCL (I2C clock) for SSP |
| Pin 16 | RC4 β PORTC bit 4 / SDA (I2C data) for SSP |
| Pin 17 | RC5 β PORTC bit 5 / SDO (SPI data out) |
| Pin 18 | RC6 β PORTC bit 6 / TX (USART asynchronous transmit) / CK (USART clock) |
| Pin 19 | RC7 β PORTC bit 7 / RX (USART asynchronous receive) / DT (USART data) |
| Pin 20 | VSS β Ground reference |
| Pin 21 | RD0 β PORTD bit 0 / PSP data bit 0 |
| Pin 22 | RD1 β PORTD bit 1 / PSP data bit 1 |
| Pin 23 | RD2 β PORTD bit 2 / PSP data bit 2 |
| Pin 24 | RD3 β PORTD bit 3 / PSP data bit 3 |
| Pin 25 | RD4 β PORTD bit 4 / PSP data bit 4 |
| Pin 26 | RD5 β PORTD bit 5 / PSP data bit 5 |
| Pin 27 | RD6 β PORTD bit 6 / PSP data bit 6 |
| Pin 28 | RD7 β PORTD bit 7 / PSP data bit 7 |
| Pin 29 | RE0 β PORTE bit 0 / /RD control for PSP |
| Pin 30 | RE1 β PORTE bit 1 / /WR control for PSP |
| Pin 31 | RE2 β PORTE bit 2 / /CS control for PSP |
| Pin 32 | VDD β Positive supply voltage |
| Pin 33 | VSS β Ground reference |
| Pin 34 | RB0 β PORTB bit 0 / external interrupt |
| Pin 35 | RB1 β PORTB bit 1 |
| Pin 36 | RB2 β PORTB bit 2 |
| Pin 37 | RB3 β PORTB bit 3 |
| Pin 38 | RB4 β PORTB bit 4 / interrupt-on-change |
| Pin 39 | RB5 β PORTB bit 5 / interrupt-on-change |
| Pin 40 | RB6 β PORTB bit 6 / ICSP clock / interrupt-on-change |
Typical Applications
PIC16LC64A-04I/P is suitable for 6 applications: Industrial Control Subsystems, Appliance Controllers, Automotive Body Electronics (Non-Safety), Sensor Signal Conditioning Front-Ends, Legacy Embedded Products Still in Service, Educational and Hobby Projects.
Industrial Control Subsystems
The PIC16LC64A-04I/P fits industrial control subsystems because its 22 digital I/O pins, three timers, and USART peripheral cover the typical sensor/actuator interface needs of a small PLC front-end or relay-replacement board. Its 3.0V to 5.5V supply range accepts both 3.3V and 5V transducers without level shifters, while the 128-byte RAM and 3.5 KB OTP program memory suit fixed-function logic such as PID loops, motor sequencing, or thermostat-style controllers. The -40C to +85C industrial temperature range is qualified for factory-floor enclosures, and the OTP memory prevents field tampering with calibrated constants. Estimated firmware headroom: roughly 2,000 14-bit instructions is sufficient for one or two feedback loops plus a serial command parser.
Recommended
Appliance Controllers
The PIC16LC64A-04I/P is well matched to appliance controllers such as washing-machine timers, microwave ovens, and dishwasher sequencers. Its 22 I/O pins drive seven-segment displays, keypads, and triac/SCR gate drivers, while the three on-chip timers generate PWM for heater elements or motor speed control. The 4 MHz RISC core delivers deterministic 1 MIPS throughput for cycle-by-cycle control, and the 15 uA active current at 5V keeps standby consumption modest. Because the OTP memory locks firmware at production time, end users cannot reflash the controller, which is desirable for safety-certified appliances. The wide 3.0V to 5.5V supply allows direct connection to rectified 5V rails.
Recommended
Automotive Body Electronics (Non-Safety)
The PIC16LC64A-04I/P serves automotive body-electronics applications such as interior lighting controllers, seat-position memory modules, and HVAC blend-door actuators. Its -40C to +85C industrial temperature range covers cabin-environment conditions, and the 22 I/O pins handle the multiple brushed-motor drivers and switch-scan inputs typical of body modules. The OTP memory prevents accidental field reprogramming that could affect vehicle warranty. Note that this part is not AEC-Q100 qualified; automotive safety-critical or under-hood applications should use AEC-Q100-qualified PIC16F equivalents such as the PIC16F74-I/P automotive version. The 3.0V to 5.5V supply tolerates load-dump transients when paired with proper clamping.
Recommended
Sensor Signal Conditioning Front-Ends
The PIC16LC64A-04I/P is suitable as the digital front-end for low-cost sensor signal conditioning modules such as thermistor bridges, photocell arrays, or simple 4-20 mA loop monitors. Its on-chip analog comparator performs threshold detection without an external op-amp, and the timers measure frequency or pulse width from sensor outputs. With 22 I/O pins, the same MCU scans a keypad, drives an indicator LED, and transmits calibration constants over the USART. The low 1 uA Sleep current at 3V/32 kHz enables battery-backed sensor nodes that wake periodically to take a measurement and return to sleep. The 128-byte RAM holds a small ring buffer for averaging.
Recommended
Legacy Embedded Products Still in Service
The PIC16LC64A-04I/P remains in service as the controller for legacy embedded products manufactured in the 1990s and 2000s, including industrial instrumentation, vending-machine controllers, security-system keypads, and HVAC zone controllers. Because these products have long field lifetimes (15-25 years), service and repair depots still need OTP replacements to fix returned units where firmware has not changed. The OTP memory ensures absolute firmware identity between factory and field repair. For these service-only applications, sourcing from authorized franchised distributors with documented traceability is essential to avoid counterfeit parts. The 40-pin PDIP package also remains friendly to through-hole rework benches.
Recommended
Educational and Hobby Projects
The PIC16LC64A-04I/P is used in educational and hobby projects because its 40-pin PDIP package fits standard 0.600-inch breadboards and its documented instruction set (35 instructions) makes it a common teaching example in PIC microcontroller courses. The 22 I/O pins are sufficient to drive multiple LEDs, a 7-segment display, and a serial LCD. The ICSP capability on RB6/RB7 allows students to program the part without removing it from the breadboard, and the 4 MHz maximum clock avoids RF interference that complicates laboratory measurements. While the OTP memory is impractical for student iteration, the same 40-pin PDIP socket can later accept a flash-based PIC16F74A-I/P without rewiring.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC64A-04I/P β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F74A-I/P | PIC16F77A-I/P | PIC16C64A-04I/P | PIC16LC64A-04/P | PIC16F737-I/P |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 40-PDIP | 40-PDIP - same | 40-PDIP - same | 40-PDIP - same | 40-PDIP - same | 40-PDIP - same |
| Program Memory | 3.5 KB OTP | 4 KB Flash | 8 KB Flash | 3.5 KB OTP | 3.5 KB OTP | 7 KB Flash |
| RAM | 128 bytes | 192 bytes | 192 bytes | 128 bytes | 128 bytes | 368 bytes |
| Max Clock | 4 MHz | 20 MHz | 20 MHz | 4 MHz | 4 MHz | 20 MHz |
| Supply Voltage | 3.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 4.5 V to 6.0 V | 3.0 V to 5.5 V | 2.0 V to 5.5 V |
| I/O Pins | 22 | 22 | 22 | 22 | 22 | 25 |
| Memory Type | OTP (one-time) | Flash (reprogrammable) | Flash (reprogrammable) | OTP (one-time) | OTP (one-time) | Flash (reprogrammable) |
| Lifecycle Status | Obsolete | Active | Active | Obsolete | Obsolete | Active |
Key Differentiators
- Flash reprogrammability (vs PIC16F74A-I/P)
- Wide low-voltage supply range (vs PIC16C64A-04I/P)
- Industrial temperature grade (vs PIC16LC64A-04/P)
Design Notes
Do not attempt to field-update firmware on the PIC16LC64A-04I/P - its OTP EPROM can be written only once per memory cell. For development, prototype with the windowed CERDIP variant (PIC16C64A-04I/P, UV-erasable) or migrate to the flash-based PIC16F74A-I/P which is pin-compatible and ICSP-reprogrammable. Estimated OTP endurance: 1 write cycle per cell; firmware re-spin requires a new batch of parts.
The PIC16LC64A-04I/P Sleep current is approximately 1 uA typical at 3V / 32 kHz per the datasheet, which is acceptable for battery-backed sensor nodes. However, ensure that the brown-out reset (BOR) configuration is enabled in the CONFIG word to avoid undefined behavior during supply ramp-up at cold start. Add a 100 nF decoupling cap on each VDD/VSS pin pair (pins 11/12 and 31/33) placed within 5 mm of the package leads.
For the 40-pin PDIP package, route the crystal traces (OSC1 / OSC2, pins 8 and 9) as short and symmetrical as possible, with the load capacitors (typically 15-33 pF) returned to a quiet ground island. Keep high-current switching traces (PORTB/PORTC sink/source >20 mA) away from the oscillator loop. The /MCLR pin (pin 1) needs a 10 kohm pull-up to VDD plus a 100 nF to VSS for noise immunity in industrial environments.
The PIC16LC64A-04I/P in 40-pin PDIP has a typical theta_JA of approximately 50 C/W in still air, so thermal management is rarely a concern at its 15 uA active current. However, in hot industrial enclosures (ambient 70 C) with continuous 5V operation, derate the clock to 32 kHz or use Sleep mode to keep junction temperature below the 125 C maximum. Estimated power dissipation at 5V / 4 MHz / full I/O load: less than 100 mW.
Compliance Information
Obsolete Microchip part. RoHS-compliant per Microchip product page; REACH compliance confirmed via DigiKey. Not AEC-Q100 qualified - this is a non-automotive grade MCU. For new automotive designs, use AEC-Q100 qualified PIC16F74-I/P or PIC16F77-I/P equivalents.
