PIC16C67-04/PT - 8-bit MCU, 14KB OTP, 4MHz, 44-TQFP | Microchip
MPN: PIC16C67-04/PT โ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.5 | $7.50 |
| 10 | $6.85 | $68.50 |
| 100 | $6.1 | $610.00 |
| 500 | $5.4 | $2,700.00 |
| 1,000 | $4.85 | $4,850.00 |
PIC16C67-04/PT Overview
What is a microcontroller? A microcontroller (MCU) is a single-chip computer containing a processor core, program memory, working RAM, I/O peripherals, and timers. Within the broader taxonomy it sits between microprocessors and system-on-chips (SoCs); an 8-bit MCU like the PIC16C67 trades absolute throughput for deterministic behavior, low cost, and ultra-low power draw. The PIC16C6x family in particular uses Harvard architecture with separate program and data buses, RISC instruction set, and OTP/EPROM/ROM program memory options. This makes MCUs like the PIC16C67-04/PT suitable for embedded control tasks where reliability and simplicity outweigh raw compute.
Key features include 14KB EPROM program memory (8K x 14 word width), 368 bytes of data RAM, 33 I/O pins across five ports, three timers, a USART, an MSSP module supporting SPI and I2C, an 8-bit ADC with 8 channels, and a watchdog timer. The /04 speed grade designates a 4 MHz maximum oscillator input, while the /PT suffix indicates the 44-pin TQFP (Thin Quad Flat Pack) package delivered in tray packaging. Pin count and memory size make this device one of the largest members of the PIC16C6x generation.
Architecturally, the PIC16C67 uses a 14-bit instruction word and a 35-instruction RISC set, allowing most instructions to execute in a single clock cycle (250 ns at 4 MHz). The Harvard bus separates program fetches from data accesses so the CPU can pre-fetch the next instruction while reading data, improving throughput without pipelining. Brown-out reset (BOR), power-on reset (POR), and the watchdog timer provide robustness in electrically noisy industrial environments.
Typical applications include industrial control subsystems, automotive body and chassis electronics (pre-CAN era designs), HVAC controls, appliance controllers, instrumentation front-ends, and embedded sensor conditioning where 33 I/O lines, three timers, and a built-in ADC reduce external component count. Designers also use it for upgrading legacy 8051 designs that need simpler firmware and lower power.
When designing with this part, plan for OTP programming: firmware bugs cannot be patched in-circuit, so emulator or windowed-ceramic-DIP samples should be used for development. Decoupling caps (0.1 uF plus 10 uF bulk) should be placed within 5 mm of VDD/VSS pins. Because the device is in a legacy product family, check Microchip's lifecycle page before committing to a long-life program.
Drop-in alternatives for PIC16C67-04/PT โ 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 PIC16C67-04/PT (same form factor and footprint) โ differing in Package, Core, Operating Temperature, Maximum Clock Frequency, Program Memory Type.
Quick Comparison Tool โ Select alternative parts for side-by-side comparison:
PIC16C66-04/PT
โ Drop-In๐ Reference alternative (not in catalog)
PIC16C67-10I/PT
โ Drop-Inโ In Stock
$5.1 / Unit
View Datasheet โPIC16C66-10I/PT
โ Drop-In๐ Reference alternative (not in catalog)
PIC16C65B-04I/PT
โ Drop-In๐ Reference alternative (not in catalog)
PIC16F877-04/PT
โ Drop-In๐ Reference alternative (not in catalog)
PIC16C67-04/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit RISC, PIC16C mid-range |
| Instruction Set | 35 instructions, 14-bit word |
| Program Memory | 14 KB (8K x 14) OTP EPROM |
| Data RAM | 368 bytes |
| I/O Pins | 33 |
| Maximum Clock Frequency | 4 MHz (04 speed grade) |
| Instruction Cycle Time | 250 ns at 4 MHz |
| Supply Voltage (VDD) | 2.5 V to 6.0 V |
| Oscillator Type | External |
| Timers | 3 (Timer0, Timer1, Timer2) |
| Communication Peripherals | USART, MSSP (SPI/I2C) |
| ADC | 8-bit, 8 channels |
| Watchdog Timer | Yes |
| Brown-out Reset | Yes |
| Package | 44-pin TQFP (PT) |
| Operating Temperature | 0C to +70C (Commercial) |
| Mounting Type | Surface Mount |
| MSL Level | 3 (168 hours) |
| Lead Free / RoHS | May not be RoHS compliant (legacy OTP) |
| Packaging | Tray |
PIC16C67-04/PT Pin Configuration
| Pin 1 | OSC1/CLKIN โ Oscillator input or external clock input |
| Pin 2 | OSC2/CLKOUT โ Oscillator output or clock output |
| Pin 3 | MCLR โ Master Clear (reset) input, active low |
| Pin 4 | RA0/AN0 โ Port A bit 0 / ADC channel 0 |
| Pin 5 | RA1/AN1 โ Port A bit 1 / ADC channel 1 |
| Pin 6 | RA2/AN2/VREF- โ Port A bit 2 / ADC channel 2 / VREF- |
| Pin 7 | RA3/AN3/VREF+ โ Port A bit 3 / ADC channel 3 / VREF+ |
| Pin 8 | RA4/T0CKI โ Port A bit 4 / Timer0 clock input |
| Pin 9 | RA5/SS/AN4 โ Port A bit 5 / SPI slave select / ADC channel 4 |
| Pin 10 | VSS โ Ground reference |
| Pin 11 | VDD โ Positive supply voltage |
| Pin 12 | RB0/INT โ Port B bit 0 / External interrupt input |
| Pin 13 | RB1 โ Port B bit 1 |
| Pin 14 | RB2 โ Port B bit 2 |
| Pin 15 | RB3 โ Port B bit 3 |
| Pin 16 | RB4 โ Port B bit 4 |
| Pin 17 | RB5 โ Port B bit 5 |
| Pin 18 | RB6/PGC โ Port B bit 6 / ICSP clock |
| Pin 19 | RB7/PGD โ Port B bit 7 / ICSP data |
| Pin 20 | RC0/T1OSO/T1CKI โ Port C bit 0 / Timer1 oscillator output / clock input |
| Pin 21 | RC1/T1OSI/CCP2 โ Port C bit 1 / Timer1 oscillator input / CCP2 |
| Pin 22 | RC2/CCP1 โ Port C bit 2 / Capture/Compare/PWM 1 |
| Pin 23 | RC3/SCK/SCL โ Port C bit 3 / SPI clock / I2C clock |
| Pin 24 | RC4/SDI/SDA โ Port C bit 4 / SPI data in / I2C data |
| Pin 25 | RC5/SDO โ Port C bit 5 / SPI data out |
| Pin 26 | RC6/TX/CK โ Port C bit 6 / USART TX / clock |
| Pin 27 | RC7/RX/DT โ Port C bit 7 / USART RX / data |
| Pin 28 | VSS โ Ground reference |
| Pin 29 | VDD โ Positive supply voltage |
| Pin 30 | RD0 โ Port D bit 0 |
| Pin 31 | RD1 โ Port D bit 1 |
| Pin 32 | RD2 โ Port D bit 2 |
| Pin 33 | RD3 โ Port D bit 3 |
| Pin 34 | RD4 โ Port D bit 4 |
| Pin 35 | RD5 โ Port D bit 5 |
| Pin 36 | RD6 โ Port D bit 6 |
| Pin 37 | RD7 โ Port D bit 7 |
| Pin 38 | RE0/RD/AN5 โ Port E bit 0 / read control / ADC channel 5 |
| Pin 39 | RE1/WR/AN6 โ Port E bit 1 / write control / ADC channel 6 |
| Pin 40 | RE2/CS/AN7 โ Port E bit 2 / chip select / ADC channel 7 |
| Pin 41 | VSS โ Ground reference |
| Pin 42 | VDD โ Positive supply voltage |
| Pin 43 | NC โ Not connected (per datasheet) |
| Pin 44 | NC โ Not connected (per datasheet) |
Typical Applications
PIC16C67-04/PT is suitable for 7 applications: Industrial Control Subsystems, Appliance Control Boards, HVAC Controllers, Instrumentation Front-Ends, Automotive Body Electronics (Legacy), Sensor Conditioning and Data Acquisition, Embedded Control Upgrades (8051 Replacement).
Industrial Control Subsystems
The PIC16C67-04/PT fits industrial control subsystems because its 33 digital I/O lines, 8-channel 8-bit ADC, three timers, and USART cover the typical sensor-fan-in plus actuator-fan-out mix found on PLC remote I/O cards and machine controllers. The wide 2.5V to 6.0V supply tolerates 5V-rail ripple from motor drivers, and brown-out reset plus watchdog timer keep the controller deterministic across long factory shifts. Place the part on a multi-layer PCB with 0.1 uF plus 10 uF decoupling and you get a robust 4 MHz control plane with 14KB of EPROM-resident ladder or state-machine logic.
Recommended
Appliance Control Boards
White-goods appliances (washing machines, dishwashers, refrigerators) are an ideal application for the PIC16C67-04/PT. The OTP EPROM secures the firmware against reverse engineering, the 33 I/O drive relays and triacs directly through optocouplers, and the integrated ADC reads temperature, water level, and motor current sensors. The 4 MHz instruction rate gives 1 MIPS performance, more than enough for sequence controllers running C or assembly state machines. Brown-out reset prevents EEPROM corruption in the appliance's power-down brown-out window.
Recommended
HVAC Controllers
Heating, ventilation, and air-conditioning controllers benefit from the PIC16C67-04/PT's extended commercial and industrial temperature grades, 14KB OTP for complex scheduling firmware, and the 8-channel ADC for reading multiple temperature zones. USART links to indoor/outdoor unit communication, while MSSP supports I2C temperature sensors. The 44-TQFP package is small enough to fit behind a thermostat display. OTP also locks the calibration constants against field tampering.
Recommended
Instrumentation Front-Ends
Portable test and measurement instruments such as handheld multimeters and bench-top panel meters use the PIC16C67-04/PT as the display-and-keypad controller. The 33 I/O drive LCD segments directly, the ADC digitizes the analog front-end, and the USART streams readings to a host PC. The fully static CMOS design draws microamps in sleep mode, extending battery life on field instruments. OTP program memory prevents accidental firmware overwrite during ESD events.
Recommended
Automotive Body Electronics (Legacy)
Pre-CAN-era automotive body controllers (window lift, mirror adjust, seat control modules) used the PIC16C67-04/PT because its 33 I/O drive H-bridges and lamp drivers, the ADC monitors current, and the watchdog catches supply transients during cranking. The OTP locks the OEM calibration. Newer designs should migrate to PIC16F877-I/PT for Flash and CAN, but for service replacements the PIC16C67-04/PT in the same 44-TQFP footprint remains a valid maintenance part.
Recommended
Sensor Conditioning and Data Acquisition
Multi-channel data-acquisition front-ends pair the PIC16C67-04/PT with external signal conditioning. The integrated 8-bit ADC with 8 channels handles 8 sensors natively, and the MSSP drives SPI or I2C ADCs for higher-resolution systems. USART streams the digitized readings to a host controller or display. At 4 MHz the CPU reads and averages the channels without CPU loading, leaving headroom for linearization math in firmware.
Recommended
Embedded Control Upgrades (8051 Replacement)
Engineers migrating from 8-bit 8051 designs often select the PIC16C67-04/PT as the upgrade target. The 35-instruction RISC set is easier to learn than the 8051's 256-opcode CISC set, the 14KB OTP holds more code than most legacy 8051 ROMs, and the 33 I/O outnumber typical 8051 port counts. Same-package 44-TQFP drop-in compatibility means existing PCBs can host the PIC after firmware porting, typically a 20-30% code-size reduction on C-compiled output.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C67-04/PT โ comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C66-04/PT | PIC16C67-10I/PT | PIC16C66-10I/PT | PIC16C65B-04I/PT | PIC16F877-04/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin TQFP (PT) | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same |
| Program Memory | 14 KB OTP EPROM | 8 KB OTP (-43%) | 14 KB OTP (same) | 8 KB OTP (-43%) | 7 KB OTP (-50%) | 14 KB Flash (reprogrammable) |
| RAM | 368 bytes | 368 bytes | 368 bytes | 368 bytes | 192 bytes (-48%) | 368 bytes |
| Maximum Clock | 4 MHz | 4 MHz | 10 MHz (+150%) | 10 MHz (+150%) | 4 MHz | 4 MHz |
| I/O Pins | 33 | 33 | 33 | 33 | 33 | 33 |
| Memory Type | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | OTP EPROM | Flash |
| Supply Voltage | 2.5 V to 6.0 V | 2.5 V to 6.0 V | 2.5 V to 6.0 V | 2.5 V to 6.0 V | 2.5 V to 6.0 V | 2.0 V to 5.5 V |
Key Differentiators
- Largest memory in PIC16C6x family (vs PIC16C66-04/PT)
- Drop-in 10 MHz upgrade path (vs PIC16C67-10I/PT)
- Pin-compatible with Flash successor (vs PIC16F877-04/PT)
Design Notes
Place a 0.1 uF ceramic decoupling capacitor within 5 mm of each VDD/VSS pin pair (pins 11/10, 29/28, 42/41), plus a single 10 uF bulk capacitor near the MCLR pin. The PIC16C67-04/PT can source/sink up to 25 mA per I/O pin (100 mA max per port, 200 mA total). Brown-out reset must be enabled in the configuration word to ensure a clean start when the rail dips below the BOR threshold, especially in industrial 24V-derived supply chains.
Because the PIC16C67-04/PT uses OTP EPROM, firmware bugs cannot be patched in-circuit. Develop on a windowed-ceramic DIP sample (PIC16C67-04/JW) or use the MPLAB ICE emulator with a TQFP adapter, and only commit production code to OTP parts after full validation. Estimate: a single OTP run takes 4-6 weeks including fab lot, so plan firmware freeze at least 8 weeks before production ramp.
Route the 4 MHz crystal traces (OSC1/OSC2, pins 1-2) short and symmetric, with the load capacitors (typically 22-33 pF) within 3 mm of the package. Keep the crystal away from high-di/dt traces such as relay coil drivers or PWM outputs on the same PCB. The 44-pin TQFP has a thermal pad that should be soldered to a grounded copper pour to reduce the junction-to-ambient thermal resistance, although the part rarely dissipates more than 200 mW at 4 MHz.
The PIC16C67-04/PT USART and MSSP pins share Port C with the parallel I/O. When using SPI or I2C, set the TRISC bits appropriately to avoid contention. The MSSP supports both 100 kHz Standard-mode and 400 kHz Fast-mode I2C; pull-up resistors on SDA/SCL (typically 4.7 k at 5V, 2.2 k at 3.3V) must be sized for the bus capacitance. For USART communication at 9600 baud or higher, enable the BRGH bit for reduced baud-rate error.
Compliance Information
RoHS and lead-free status not explicitly stated in the verified web data; the PIC16C6x family is a legacy OTP generation and many date codes predate RoHS. AEC-Q100 qualification not stated - choose PIC16F variants with automotive qualification for vehicle applications. Verify compliance via the supplier CoC for specific date codes.