PIC16C65A-04/PQ - 8-Bit 4MHz 7KB OTP MCU 44-MQFP | Microchip
MPN: PIC16C65A-04/PQ ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $10.02 | $10.02 |
| 10 | $9.15 | $91.50 |
| 100 | $7.85 | $785.00 |
| 500 | $6.95 | $3,475.00 |
| 1,000 | $6.2 | $6,200.00 |
PIC16C65A-04/PQ Overview
Background: A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory, working RAM, and programmable I/O peripherals. PIC microcontrollers from Microchip Technology use a Harvard RISC architecture, separating program and data buses to allow instruction fetch and operand access in a single cycle. The PIC16C family specifically targets cost-sensitive embedded control and is a predecessor to the flash-based PIC16F line.
Key features include a fully static design that supports DC to 4 MHz operation (with -04 speed grade), low-power consumption of 15 uA typical at 5V/4 MHz and 1 uA typical at 3V/32 kHz, and a high-performance RISC CPU with single-cycle instructions except for program branches which take two cycles. The part supports commercial, industrial, and extended temperature ranges, making it suitable for both consumer and harsh-environment deployments.
Architecturally, the PIC16C65A combines an 8-bit ALU with a 14-bit instruction word, 8-level hardware stack, and a powerful set of peripherals including timers, a synchronous serial port (SSP) supporting SPI and I2C, a USART, and an 8-bit parallel slave port for external memory or bused interfaces. This integration allows level-C back-channel communication with peripheral ASICs without external glue logic.
Typical applications include industrial automation controllers, motor control front-ends, sensor signal conditioning, embedded display drivers, and legacy replacement of older 8051-based designs. Its OTP program memory and EPROM windowed variants simplify field programming during prototyping and low-volume production.
When designing with this MCU, ensure the oscillator configuration matches the application: the -04 speed grade limits the clock to 4 MHz, so for higher throughput the PIC16C65A-10 or PIC16C65A-20 variants are required. Plan for a 1-2 ms power-on delay before code execution to allow the oscillator to stabilize.
This page synthesizes distributor pricing, package dimensions, and drop-in alternatives drawn from across Microchip's PIC16C6X portfolio, providing practical sourcing and engineering context not found in the standalone datasheet.
Drop-in alternatives for PIC16C65A-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 PIC16C65A-04/PQ (same form factor and footprint) — differing in Operating Temperature, CCP Modules, Package, Program Memory Type, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C65A-10/PQ
✅ Drop-In✓ In Stock
$6.1 / Unit
View Datasheet →PIC16C65A-20/PQ
✅ Drop-In✓ In Stock
$4.61 / Unit
View Datasheet →PIC16C65B-04/PQ
✅ Drop-In✓ In Stock
$10.25 / Unit
View Datasheet →PIC16C65A-04I/PQ
✅ Drop-In✓ In Stock
$9.95 / Unit
View Datasheet →PIC16C65A-04E/PQ
✅ Drop-In✓ In Stock
$5.25 / Unit
View Datasheet →PIC16LC65B-04/PQ
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C65A-04/PQ Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit Microcontroller (MCU) |
| Core Architecture | PIC16C RISC (Harvard) |
| Program Memory Size | 7 KB (4K x 14) OTP EPROM |
| RAM Size | 192 bytes |
| Maximum Clock Speed | 4 MHz (-04 speed grade) |
| Supply Voltage (VDD) | 4.0 V to 6.0 V (5 V typical) |
| I/O Pins | 33 |
| Package Type | 44-MQFP (Metric Quad Flat Pack, 10x10 mm) |
| Mounting Type | Surface Mount |
| Instruction Set | 35 single-word instructions |
| Instruction Cycle | 1 cycle (2 cycles for branches) |
| Operating Temperature Range | 0C to +70C (Commercial) |
| Power Consumption (Active) | 15 uA typical at 5 V / 4 MHz |
| Power Consumption (Sleep) | 1 uA typical at 3 V / 32 kHz |
| Peripherals | Timers, USART, SSP (SPI/I2C), Parallel Slave Port |
PIC16C65A-04/PQ Pin Configuration
| Pin 1 | /MCLR — Master Clear (Reset) input, active low |
| Pin 2 | RA0/AN0 — Port A bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — Port A bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2 — Port A bit 2 / Analog input 2 |
| Pin 5 | RA3/AN3/VREF — Port A bit 3 / Analog input 3 / Voltage reference |
| Pin 6 | RA4/T0CKI — Port A bit 4 / Timer 0 clock input |
| Pin 7 | RA5/AN4/SS — Port A bit 5 / Analog input 4 / SPI slave select |
| Pin 8 | OSC1/CLKIN — Oscillator crystal input / external clock input |
| Pin 9 | OSC2/CLKOUT — Oscillator crystal output / clock output |
| Pin 10 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer 1 oscillator output / clock input |
| Pin 11 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer 1 oscillator input / CCP2 |
| Pin 12 | RC2/CCP1 — Port C bit 2 / Capture Compare PWM 1 |
| Pin 13 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 14 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 15 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 16 | RC6/TX/CK — Port C bit 6 / USART transmit / clock |
| Pin 17 | RC7/RX/DT — Port C bit 7 / USART receive / data |
| Pin 18 | VSS — Ground reference |
| Pin 19 | VSS — Ground reference |
| Pin 20 | RB0/INT — Port B bit 0 / External interrupt |
| Pin 21 | RB1 — Port B bit 1 |
| Pin 22 | RB2 — Port B bit 2 |
| Pin 23 | RB3 — Port B bit 3 |
| Pin 24 | RB4 — Port B bit 4 |
| Pin 25 | RB5 — Port B bit 5 |
| Pin 26 | RB6 — Port B bit 6 |
| Pin 27 | RB7 — Port B bit 7 |
| Pin 28 | RD0/PSP0 — Port D bit 0 / Parallel Slave Port bit 0 |
| Pin 29 | RD1/PSP1 — Port D bit 1 / Parallel Slave Port bit 1 |
| Pin 30 | RD2/PSP2 — Port D bit 2 / Parallel Slave Port bit 2 |
| Pin 31 | RD3/PSP3 — Port D bit 3 / Parallel Slave Port bit 3 |
| Pin 32 | RD4/PSP4 — Port D bit 4 / Parallel Slave Port bit 4 |
| Pin 33 | RD5/PSP5 — Port D bit 5 / Parallel Slave Port bit 5 |
| Pin 34 | RD6/PSP6 — Port D bit 6 / Parallel Slave Port bit 6 |
| Pin 35 | RD7/PSP7 — Port D bit 7 / Parallel Slave Port bit 7 |
| Pin 36 | RE0/RD — Port E bit 0 / Parallel Slave Port read control |
| Pin 37 | RE1/WR — Port E bit 1 / Parallel Slave Port write control |
| Pin 38 | RE2/CS — Port E bit 2 / Parallel Slave Port chip select |
| Pin 39 | VDD — Positive supply voltage |
| Pin 40 | VDD — Positive supply voltage |
| Pin 41 | NC — Not connected (per datasheet) |
| Pin 42 | NC — Not connected (per datasheet) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC16C65A-04/PQ is suitable for 6 applications: Industrial Automation Controller, Motor Control Front-End, Sensor Signal Conditioning Hub, Embedded Display Driver, Legacy 8051 Replacement Design, Building Automation and HVAC Controller.
Industrial Automation Controller
The PIC16C65A-04/PQ fits industrial automation controller designs that require 33 digital I/O pins to interface with sensors, relays, and motor drivers without external I/O expanders. Its 7 KB OTP program memory holds typical ladder-logic replacement firmware and PID loop handlers. The 4 MHz clock is sufficient for sequencing scan times of 1-10 ms. The 44-MQFP package provides a small PCB footprint suitable for DIN-rail mounted controller boards. Power consumption at 15 uA active and 1 uA sleep allows battery-backed operation during power-loss events. The integrated USART supports Modbus RTU communication with industrial HMIs and PLCs.
Recommended
Motor Control Front-End
The PIC16C65A-04/PQ serves as a motor control front-end for low-to-medium complexity brushless DC and stepper motor drives. Its 4 MHz clock drives PWM generation for speed control loops, while the 33 I/O pins handle Hall sensor inputs, quadrature encoder interfaces, and direction-control outputs. The integrated timers provide input capture for RPM measurement with 1 us resolution at 4 MHz. The 7 KB OTP holds commutation tables and PI controller coefficients. Designers benefit from the 44-MQFP package's compact footprint when designing integrated motor-controller boards.
Recommended
Sensor Signal Conditioning Hub
The PIC16C65A-04/PQ functions as a sensor signal conditioning hub in multi-sensor embedded systems, aggregating inputs from temperature, pressure, and flow sensors via its 33 I/O pins. The integrated ADC (where present on this family) and analog comparators handle linear sensor signals directly. The 192-byte RAM supports moving-average filtering and threshold detection without external memory. The synchronous serial port (SSP) interfaces with SPI-based digital sensors while the USART provides wired connectivity to upstream controllers. The 4 MHz clock supports sampling rates up to 100 kHz for typical sensor arrays.
Recommended
Embedded Display Driver
The PIC16C65A-04/PQ drives character LCD and small graphic OLED displays in embedded HMI applications. Its 33 I/O pins provide direct interface to 4-bit and 8-bit LCD buses plus 3-4 control lines. The 7 KB OTP holds multi-language font tables and menu structures. The SSP port can drive SPI OLED displays, while the parallel slave port interfaces with character LCD modules. At 4 MHz, refresh rates of 50-100 Hz are achievable for 16x2 and 20x4 character displays. Low-power sleep modes at 1 uA allow battery-powered HMI remotes.
Recommended
Legacy 8051 Replacement Design
The PIC16C65A-04/PQ is a strong replacement for legacy 8051-family microcontrollers in cost-sensitive embedded products where the original 8051 is end-of-life. With 7 KB OTP (versus typical 4-8 KB 8051 ROM), 33 I/O (versus 32-40 on 8051), and a RISC core with single-cycle instruction execution, the PIC16C65A delivers 2-4x the MIPS per MHz compared to legacy 8051 designs. The 44-MQFP package offers a modern surface-mount alternative to PDIP-40 8051 packages. Firmware must be rewritten due to different instruction set, but the C compiler ecosystem (XC8AC-program) supports migration projects.
Recommended
Building Automation and HVAC Controller
The PIC16C65A-04/PQ supports building automation and HVAC controller applications including zone damper control, thermostat endpoints, and VAV box controllers. Its 33 I/O pins handle multiple relay outputs for fan speed control and analog inputs for temperature/humidity sensors. The 7 KB OTP holds scheduling logic and PID heating/cooling algorithms. The integrated USART interfaces with BACnet or Modbus building automation networks. At 4 MHz, the device supports typical 250 ms control loop update rates required for HVAC applications. The wide 4-6V supply range accommodates 5V industrial rail environments.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C65A-04/PQ — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C65A-10/PQ | PIC16C65A-20/PQ | PIC16C65B-04/PQ | PIC16C65A-04I/PQ | PIC16C65A-04E/PQ | PIC16LC65B-04/PQ |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-MQFP (10x10 mm) | 44-MQFP (10x10 mm) - same | 44-MQFP (10x10 mm) - same | 44-MQFP (10x10 mm) - same | 44-MQFP (10x10 mm) - same | 44-MQFP (10x10 mm) - same | 44-MQFP (10x10 mm) - same |
| Maximum Clock Speed | 4 MHz | 10 MHz | 20 MHz | 4 MHz | 4 MHz | 4 MHz | 4 MHz |
| Program Memory | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP | 7 KB OTP |
| RAM | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes | 192 bytes |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 | 33 |
| Supply Voltage | 4.0 V to 6.0 V | 4.0 V to 6.0 V | 4.0 V to 6.0 V | 4.0 V to 6.0 V | 4.0 V to 6.0 V | 4.0 V to 6.0 V | 2.5 V to 6.0 V (low-voltage) |
| Operating Temperature | 0C to +70C (Commercial) | 0C to +70C (Commercial) | 0C to +70C (Commercial) | 0C to +70C (Commercial) | -40C to +85C (Industrial) | -40C to +125C (Extended) | 0C to +70C (Commercial) |
| Silicon Revision | A | A | A | B | A | A | B (LC) |
Key Differentiators
- Drop-in speed upgrade path within same family (vs PIC16C65A-10/PQ)
- Industrial temperature variant with identical footprint (vs PIC16C65A-04I/PQ)
- Extended temperature variant for harsh environments (vs PIC16C65A-04E/PQ)
- Low-voltage operation variant (vs PIC16LC65B-04/PQ)
Design Notes
The PIC16C65A-04/PQ operates from 4.0V to 6.0V supply; for 3.3V systems, select the PIC16LC65B-04/PQ variant which operates down to 2.5V. Add a 100nF decoupling capacitor as close as possible to the VDD pins (39, 40) and a 10uF bulk capacitor on the supply rail. For battery-backed applications, the 1 uA sleep current at 3V/32 kHz enables months of backup operation.
Place the crystal oscillator or external clock source within 1 cm of the OSC1 (pin 8) and OSC2 (pin 9) pins to minimize parasitic capacitance. Route the /MCLR line (pin 1) with a 10 kohm pull-up to VDD and a 100 nF capacitor to ground for proper reset behavior. The 44-MQFP package has two VDD and two VSS pins; both must be connected for proper operation and noise immunity.
Do not exceed the maximum clock input frequency of 4 MHz for the -04 speed grade; higher frequencies require the -10 or -20 variants. The OTP (One-Time-Programmable) memory cannot be erased - ensure firmware is fully validated before programming in production. The parallel slave port (PSP) requires external bus-control logic and is not available while the port D/E pins are configured as general I/O.
The PIC16C65A-04/PQ in the 44-MQFP package has typical power dissipation of approximately 25 mW at 5V/4 MHz active and less than 5 uW in sleep mode. No heatsink is required for normal operation. For enclosed applications with limited airflow, derate ambient temperature by 5-10C to account for self-heating under continuous full-load conditions.
Compliance Information
Compliance information not present in the verified web data; PIC16C family MCUs are legacy parts predating widespread RoHS compliance mandates - check with Microchip for current compliance status.
