PIC16LC65A-04/PQ - 4MHz 8-Bit OTP MCU 7KB | Microchip PQFP-44
MPN: PIC16LC65A-04/PQ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.5 | $9.50 |
| 10 | $8.75 | $87.50 |
| 100 | $7.9 | $790.00 |
| 500 | $7.1 | $3,550.00 |
| 1,000 | $6.5 | $6,500.00 |
PIC16LC65A-04/PQ Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, RAM, program memory, and peripherals on one die. Within the broader taxonomy, the PIC16LC65A sits in the 8-bit MCU category, beneath general-purpose microcontrollers and semiconductor ICs. The 'LC' suffix denotes Microchip's low-voltage CMOS process, allowing operation down to 3.0V for battery-friendly applications, while the 'A' revision is an enhanced silicon revision of the original PIC16C65 core. The /PQ suffix uniquely identifies the 44-pin PQFP package variant for surface-mount assembly.
Key specifications include 35 single-word instructions (all single-cycle except two-cycle branches), a 14-bit instruction set, 8-channel 8-bit analog-to-digital conversion, USART, SSP, and capture/compare/PWM peripherals. The device integrates a watchdog timer with on-chip RC oscillator, power-on reset, power-saving sleep mode, and an operating speed up to DC-4 MHz at 5V. The PIC16LC65A-04/PQ provides enhanced features including code protection, brown-out detection, and in-circuit serial programming.
Architecturally, the PIC16LC65A-04/PQ uses a Harvard architecture with separate program and data buses, allowing instruction fetch and operand access in a single cycle. Its CMOS implementation gives low power consumption, with typical standby currents under 1 µA in sleep mode. The 4 MHz oscillator speed (the '04' suffix indicates 4 MHz timing) makes the part suitable for control loops, simple user interfaces, and serial-protocol bridging where higher MIPS are unnecessary.
Typical applications include industrial automation controllers, HVAC control boards, security alarm panels, automotive body electronics (non-safety), remote sensor nodes, and consumer appliances. Its 33 I/O lines comfortably drive LED matrices, keypads, LCDs, and relay banks. The PIC16LC65A-04/PQ also serves as a serial-protocol converter between RS-232, I²C, and SPI peripherals in mixed-system designs.
When designing with this part, account for OTP memory constraints: code must be perfect before commit because OTP cannot be erased. For prototyping, consider the windowed ceramic DIP variant (PIC16LC65A-04/JW) for UV-erase development. Use the ICD (In-Circuit Debugger) header for real-time emulation prior to committing OTP bits.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, providing engineers a single reference for sourcing the PIC16LC65A-04/PQ.
Drop-in alternatives for PIC16LC65A-04/PQ — 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 PIC16LC65A-04/PQ (same form factor and footprint) — differing in Program Memory Type, ADC, Communication Interfaces, Package, Watchdog Timer.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16LC65A-04E/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC65A-04I/PQ
✅ Drop-In✓ In Stock
$5.3 / Unit
View Datasheet →PIC16LC65A-04/L
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC65AT-04/PQ
✅ Drop-In✓ In Stock
$10.75 / Unit
View Datasheet →PIC16LC65BT-04/PQ
✅ Drop-In✓ In Stock
$5.04 / Unit
View Datasheet →PIC16LC64A-04/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16LC65A-04/PQ Maximum Ratings & Electrical Characteristics
| Family | PIC® 16C |
| Core | 8-bit RISC PIC |
| Program Memory Type | OTP (One-Time-Programmable) |
| Program Memory Size | 7 KB (4K x 14) |
| RAM | 192 bytes |
| EEPROM Data Memory | None (OTP variant) |
| Maximum Clock Speed | 4 MHz |
| Supply Voltage (Vcc) | 3.0 V to 5.5 V |
| I/O Pins | 33 |
| ADC | 8 channels x 8 bits |
| Instruction Set | 35 instructions, 14-bit word |
| Peripherals | USART, SSP (I²C/SPI), CCP, 8-ch 8-bit ADC |
| Package / Case | 44-pin PQFP (MQFP) - Plastic Quad Flat Pack |
| Mounting Type | Surface Mount |
| Operating Temperature | 0°C to +70°C |
| Architecture | Harvard (separate program/data bus) |
| Watchdog Timer | Yes, with on-chip RC oscillator |
| In-Circuit Programming | Yes (ICSP) |
| RoHS Status | unknown |
| Lifecycle Stage | ACTIVE |
PIC16LC65A-04/PQ Pin Configuration
| Pin 1 | RA0/AN0 — PORTA bit 0 / analog input channel 0 |
| Pin 2 | RA1/AN1 — PORTA bit 1 / analog input channel 1 |
| Pin 3 | RA2/AN2 — PORTA bit 2 / analog input channel 2 |
| Pin 4 | RA3/AN3/Vref — PORTA bit 3 / analog input channel 3 / ADC reference |
| Pin 5 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 6 | RA5/AN4/SS — PORTA bit 5 / analog input channel 4 / SPI slave select |
| Pin 7 | OSC1/CLKIN — Oscillator input / external clock input |
| Pin 8 | OSC2/CLKOUT — Oscillator output / clock output |
| Pin 9 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock |
| Pin 10 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 |
| Pin 11 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM/capture/compare |
| Pin 12 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I²C clock |
| Pin 13 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I²C data |
| Pin 14 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 15 | RC6/TX/CK — PORTC bit 6 / USART TX / USART clock |
| Pin 16 | RC7/RX/DT — PORTC bit 7 / USART RX / USART data |
| Pin 17 | Vss — Ground |
| Pin 18 | VDD — Positive supply voltage |
| Pin 19 | RB0/INT — PORTB bit 0 / external interrupt |
| Pin 20 | RB1 — PORTB bit 1 |
| Pin 21 | RB2 — PORTB bit 2 |
| Pin 22 | RB3/PGM — PORTB bit 3 / low-voltage programming |
| Pin 23 | RB4 — PORTB bit 4 |
| Pin 24 | RB5 — PORTB bit 5 |
| Pin 25 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 26 | RB7/PGD — PORTB bit 7 / ICSP data |
| Pin 27 | Vss — Ground |
| Pin 28 | VDD — Positive supply voltage |
| Pin 29 | RD0 — PORTD bit 0 |
| Pin 30 | RD1 — PORTD bit 1 |
| Pin 31 | RD2 — PORTD bit 2 |
| Pin 32 | RD3 — PORTD bit 3 |
| Pin 33 | RD4 — PORTD bit 4 |
| Pin 34 | RD5 — PORTD bit 5 |
| Pin 35 | RD6 — PORTD bit 6 |
| Pin 36 | RD7 — PORTD bit 7 |
| Pin 37 | Vss — Ground |
| Pin 38 | VDD — Positive supply voltage |
| Pin 39 | RE0/RD/AN5 — PORTE bit 0 / read control / analog input channel 5 |
| Pin 40 | RE1/WR/AN6 — PORTE bit 1 / write control / analog input channel 6 |
| Pin 41 | RE2/CS/AN7 — PORTE bit 2 / chip select / analog input channel 7 |
| Pin 42 | Vss — Ground |
| Pin 43 | VDD — Positive supply voltage |
| Pin 44 | MCLR/VPP — Master clear reset / programming voltage |
Typical Applications
PIC16LC65A-04/PQ is suitable for 6 applications: Industrial Automation Controller, HVAC Control Board, Security Alarm Panel, Automotive Body Electronics, Consumer Appliance Control, RS-232 to I²C/SPI Protocol Converter.
Industrial Automation Controller
The PIC16LC65A-04/PQ's 33 I/O pins, 8-channel 8-bit ADC, and 4 MHz RISC core fit industrial control panels requiring multiple sensor inputs and relay outputs. The 7KB OTP program memory stores control algorithms for PLC-like sequencing, while the 192-byte RAM handles real-time I/O updates. At 3.0V to 5.5V operation, the part interfaces directly with 5V logic and 24V optically-isolated inputs via simple resistor dividers. The Harvard architecture's deterministic 250 ns instruction cycle supports predictable control loop timing for motor starters, conveyor logic, and HMI button debounce.
Recommended
HVAC Control Board
The PIC16LC65A-04/PQ suits HVAC thermostats and zone controllers where 33 I/O lines drive triac outputs, scan keypads, and read temperature/humidity sensors via the integrated 8-bit ADC. Its 3.0V to 5.5V operation runs directly from rectified 24VAC wall transformer rails, and the low-power CMOS process keeps standby current below 1 µA in sleep mode, satisfying Energy Star idle requirements. The 4 MHz clock provides 4 MIPS throughput, sufficient for PID loop execution and LCD interface scanning. OTP memory prevents firmware tampering in field-deployed equipment.
Recommended
Security Alarm Panel
The PIC16LC65A-04/PQ's 33 I/O lines scan up to 16 zones with EOL resistors, drive a keypad backlight, communicate with central stations via the on-chip USART, and sound piezo sirens through PWM outputs. The 7KB OTP stores zone configuration, event logs, and communication protocols. Brown-out detection and the watchdog timer with on-chip RC oscillator prevent lockup during power glitches, while the Harvard architecture ensures the alarm fires deterministically when sensors trigger. The PQFP-44 package accommodates the 33 I/O footprint plus ICSP programming.
Recommended
Automotive Body Electronics
The PIC16LC65A-04/PQ is suitable for non-safety automotive body controllers such as door modules, seat controllers, and mirror adjusters where 33 I/O lines handle switch scanning, motor PWM, and LIN-bus communication. The 4 MHz clock and Harvard architecture provide deterministic response for switch debouncing and motor speed control. While the standard /PQ variant operates 0°C to +70°C, the -04E and -04I temperature grades extend to +125°C for under-dash and engine-bay-adjacent locations. OTP memory prevents firmware reverse-engineering, a plus for OEM IP protection.
Recommended
Consumer Appliance Control
The PIC16LC65A-04/PQ powers washing machines, dishwashers, microwave ovens, and small kitchen appliances where 33 I/O lines drive 7-segment displays, scan capacitive touch keypads, and control TRIAC-based heater elements via the CCP peripheral. The 8-channel 8-bit ADC reads temperature probes, water level sensors, and motor current feedback. The 7KB OTP stores cycle programs for wash profiles or cooking recipes, while the Harvard bus ensures cycle timings remain accurate. The 4 MHz operation and low sleep current (<1 µA) help meet energy-efficiency regulations.
Recommended
RS-232 to I²C/SPI Protocol Converter
The PIC16LC65A-04/PQ bridges legacy RS-232 host equipment with modern I²C and SPI peripherals, leveraging the on-chip USART for serial communication and the SSP module for I²C/SPI transactions. At 4 MHz, the part has enough bandwidth to handle 115200 baud UART traffic and 400 kHz I²C simultaneously. The 192-byte RAM acts as a buffer between the two buses, and the 33 I/O lines allow status LEDs and configuration DIP switches. The Harvard architecture ensures deterministic protocol timing, critical for industrial gateways and instrumentation front-ends.
Recommended
Recommended Products Summary
Engineering reference data for PIC16LC65A-04/PQ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16LC65A-04E/PQ | PIC16LC65A-04I/PQ | PIC16LC65A-04/L | PIC16LC65AT-04/PQ | PIC16LC65BT-04/PQ | PIC16LC64A-04/SO |
|---|---|---|---|---|---|---|---|
| Package | PQFP-44 (MQFP) | PQFP-44 (MQFP) - same | PQFP-44 (MQFP) - same | PQFP-44 (MQFP) - same | PQFP-44 (MQFP) - same | PQFP-44 (MQFP) - same | SOIC-28 - different |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP |
| Maximum Clock Speed | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Supply Voltage | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V | 3.0 V to 5.5 V |
| Operating Temperature | 0°C to +70°C | -40°C to +125°C | -40°C to +85°C | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C | 0°C to +70°C |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 | 22 |
| RAM | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes |
Key Differentiators
- Extended temperature range option in identical PQFP-44 footprint (vs PIC16LC65A-04E/PQ)
- Lower-voltage operation for battery-powered designs (vs PIC16C65A-04/PQ)
- Firmware IP protection via One-Time-Programmable memory (vs PIC16F65A)
Design Notes
The PIC16LC65A-04/PQ requires a stable 3.0V to 5.5V supply; per-pin current sink/source is rated 25 mA with total package dissipation of 1.0 W. Place a 0.1 µF ceramic decoupling capacitor close to each VDD pin (pins 18, 28, 38, 43) and a 10 µF bulk electrolytic at the board's power entry. Brown-out reset should be configured to 2.5V (BOREN=1, BORV=1) for 3.3V systems to avoid code-lockup during supply droops. The MCLR pin (44) needs a 10 kΩ pull-up to VDD; if unused, tie directly to VDD.
The PQFP-44 package has a 0.80 mm lead pitch requiring careful PCB layout: use 0.30 mm-wide traces with 0.45 mm pads, and add via-in-pad or tented vias for thermal relief under the die. Maintain at least 0.2 mm clearance between traces and package leads for solder mask dam integrity. Place the 4 MHz crystal or resonator within 5 mm of pins 7 (OSC1) and 8 (OSC2), with grounded guard traces around both nodes. Add a ground plane on layer 2 directly under the MCU for EMI shielding; the PIC16LC65A is susceptible to digital noise corrupting ADC readings above 8 MHz switching signals.
OTP memory cannot be erased after programming, so firmware must be fully validated before committing bits; use the windowed PIC16LC65A-04/JW ceramic DIP or emulator for development. Configuration bits include watchdog enable (WDT), brown-out reset (BOR), code protection (CP), and oscillator selection (HS/XT/LP/RC); misconfiguration can lock the device or cause silent failure. The ICSP pins RB6 (PGC) and RB7 (PGD) must not be pulled low at power-up or the MCU enters programming mode unexpectedly. Finally, ensure the ADC reference (RA3) is bypassed with 0.1 µF ceramic if used, or floating noise will corrupt conversions.
When using the 4 MHz internal RC oscillator or external crystal, the clock output on pin 8 (CLKOUT) can couple to adjacent analog inputs on pins 5-6 (RA4/RA5); maintain 2 mm spacing or use a guard trace tied to analog ground. The CCP1 PWM output on pin 11 (RC2) operates at up to 10 kHz with 10-bit duty resolution; add a 100 Ω series resistor to the gate-driver input to dampen ringing. I²C lines (RC3/SCK, RC4/SDI) need 4.7 kΩ pull-ups to VDD; verify against the 3.3V or 5V rail per system voltage. USART lines (RC6/TX, RC7/RX) should be terminated with 100 Ω in series for long cable runs.
Compliance Information
RoHS/REACH status not confirmed in verified web data; the L suffix variant (-04/L) confirms lead-free finish availability. The standard PQFP-44 package uses matte-tin plating compatible with lead-free reflow up to 260°C peak per JEDEC J-STD-020. AEC-Q100 qualification does not apply to the 0°C to +70°C commercial variant; the -04E grade is more commonly specified for automotive use.
