PIC16C642-10I/SO - 8-Bit OTP MCU, 7KB EPROM, 22 I/O | Microchip
MPN: PIC16C642-10I/SO β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.45 | $3.45 |
| 10 | $3.1 | $31.00 |
| 100 | $2.65 | $265.00 |
| 500 | $2.3 | $1,150.00 |
| 1,000 | $2.05 | $2,050.00 |
PIC16C642-10I/SO Overview
Background context: An 8-bit microcontroller is a single-chip computer integrating a CPU, non-volatile program memory (here, OTP EPROM), working RAM, and peripherals into one package. Within the taxonomy, the PIC16C642 belongs to the OTP-EPROM PIC16 mid-range family, which sits below the PIC18 family and above base-line PIC10/12/14 devices. These MCUs are widely used in cost-sensitive, low-volume, or ruggedized embedded designs where field reprogramming is not required and the simplicity of the PIC RISC core outweighs the larger code density of 16-bit alternatives.
Key features include a 200 ns instruction cycle, 8-level hardware stack, power-on reset, brown-out detection, watchdog timer with its own on-chip RC oscillator, programmable code protection, and selectable oscillator modes (RC, XT, HS, LP). The two on-chip analog comparators feature programmable on-chip voltage reference and rail-to-rail inputs, allowing direct interface to analog sensors without external op-amps. Code protection and an ICD-friendly architecture simplify prototyping and production.
The architecture combines a RISC Harvard CPU with separate program and data buses, achieving deterministic single-cycle execution except for program branches (two cycles). With 128 bytes of EEPROM data memory on-die, designers can store calibration constants, serial numbers, or runtime configuration that survives power cycles without external storage.
Common applications include industrial control panels, appliance controllers, automotive body modules, security-system sensor interfaces, and consumer remote controls. The wide supply range and on-chip analog comparators suit battery chargers, and the 22 I/O pins comfortably drive keypads, LED arrays, and small character displays.
Design tip: choose the oscillator mode carefully - HS requires an external crystal up to 20 MHz, XT up to 4 MHz, LP minimizes quiescent current for battery operation, and RC mode uses an external resistor/capacitor for the lowest BOM cost. Always place a decoupling capacitor within 5 mm of VDD and use an isolation resistor on MCLR for in-circuit debugging.
This page synthesizes distributor pricing tiers, same-brand drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16C642-10I/SO 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 PIC16C642-10I/SO (same form factor and footprint) β differing in Program Memory Type, Maximum Clock Frequency, Core Architecture, Operating Temperature Range, Package Type.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16C642-04E/SO
β Drop-Inβ In Stock
$3.62 / Unit
View Datasheet βPIC16C642-04/SO
β Drop-Inβ In Stock
$4.3 / Unit
View Datasheet βPIC16C642T-10I/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16C642-10E/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16F628-I/SO
β Drop-Inπ Reference alternative (not in catalog)
PIC16C642-10I/SO Maximum Ratings & Electrical Characteristics
| Program Memory Type | OTP EPROM |
| Program Memory Size | 7 KB (4K x 14) |
| Data EEPROM | 128 bytes |
| RAM | 176 bytes |
| CPU Core | 8-bit PIC16 RISC |
| Instruction Set | 35 single-word instructions |
| Instruction Cycle Time | 200 ns |
| Maximum Clock Frequency | 10 MHz |
| Supply Voltage (VDD) | 4.0 V to 5.5 V |
| I/O Pins | 22 |
| Analog Comparators | 2 (with programmable on-chip Vref) |
| Timers | Timer0 (8-bit), Timer1 (16-bit), Timer2 (8-bit with PWM) |
| Capture/Compare/PWM | 1 CCP module |
| Hardware Stack | 8 levels |
| Watchdog Timer | Yes (with dedicated on-chip RC oscillator) |
| Brown-out Reset | Yes |
| Power-on Reset | Yes |
| In-Circuit Debug | ICD-capable |
| Oscillator Modes | RC, XT, HS, LP |
| Operating Temperature Range | -40 C to +85 C (Industrial, 'I' suffix) |
| Package Type | 28-pin SOIC (300-mil, 'SO' suffix) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited floor life) |
PIC16C642-10I/SO Pin Configuration
| Pin 1 | RA2 β PORTA bit 2 (digital I/O, analog input) |
| Pin 2 | RA3 β PORTA bit 3 (digital I/O, analog input) |
| Pin 3 | RA4/T0CKI β PORTA bit 4 / Timer0 clock input (open-drain) |
| Pin 4 | RA5 β PORTA bit 5 (digital I/O, analog input) |
| Pin 5 | VSS β Ground reference |
| Pin 6 | RB0/INT β PORTB bit 0 / external interrupt input |
| Pin 7 | RB1 β PORTB bit 1 |
| Pin 8 | RB2 β PORTB bit 2 |
| Pin 9 | RB3 β PORTB bit 3 |
| Pin 10 | RB4 β PORTB bit 4 (interrupt-on-change) |
| Pin 11 | RB5 β PORTB bit 5 (interrupt-on-change) |
| Pin 12 | RB6 β PORTB bit 6 (interrupt-on-change, ICD clock) |
| Pin 13 | RB7 β PORTB bit 7 (interrupt-on-change, ICD data) |
| Pin 14 | VDD β Positive supply (4.0 V to 5.5 V) |
| Pin 15 | OSC2/CLKOUT β Oscillator output / clock out |
| Pin 16 | OSC1/CLKIN β Oscillator input / external clock in |
| Pin 17 | RC0 β PORTC bit 0 |
| Pin 18 | RC1 β PORTC bit 1 |
| Pin 19 | RC2/CCP1 β PORTC bit 2 / CCP1 PWM output |
| Pin 20 | RC3 β PORTC bit 3 |
| Pin 21 | RC4 β PORTC bit 4 |
| Pin 22 | RC5 β PORTC bit 5 |
| Pin 23 | RC6 β PORTC bit 6 |
| Pin 24 | RC7 β PORTC bit 7 |
| Pin 25 | MCLR/VPP β Master clear (reset) / programming voltage |
| Pin 26 | RA0 β PORTA bit 0 (analog comparator input) |
| Pin 27 | RA1 β PORTA bit 1 (analog comparator input) |
| Pin 28 | VREF β Comparator reference voltage input |
Typical Applications
PIC16C642-10I/SO is suitable for 7 applications: Industrial Control Panel Interface, Appliance Motor Controller, Automotive Body Electronics Module, Security System Sensor Interface, Remote Control Transmitter, Battery Charger Controller, Smart Sensor Node with LED Display.
Industrial Control Panel Interface
The PIC16C642-10I/SO is well suited to industrial HMI panels where 22 I/O pins drive 4x4 keypads and multiplexed 7-segment displays without external logic. Its 7 KB OTP program memory accommodates state-machine firmware for menu navigation, while the two on-chip analog comparators monitor panel supply voltage and over-temperature conditions via NTC thermistors. Industrial -40C to +85C operation and brown-out reset ensure reliable cold-crank and brown-out recovery on factory DC bus rails.
Recommended
Appliance Motor Controller
In washing machines, dishwashers, and small kitchen appliances, the PIC16C642-10I/SO provides closed-loop control of universal motors and triac-driven pumps. The CCP module generates PWM at configurable duty cycles for soft-start ramps, while Timer1 captures zero-crossing events from the mains for phase-angle control. The 176-byte RAM holds calibration tables for wash-cycle algorithms, and the on-chip comparators sense motor current via shunt resistors for stall detection without a dedicated op-amp.
Recommended
Automotive Body Electronics Module
The PIC16C642-10I/SO is widely deployed in body control modules for seat controllers, mirror adjusters, and lighting clusters. Its 22 I/O pins drive multiple relays and LEDs while the Watchdog Timer with dedicated RC oscillator resets the MCU on software lockup. The two comparators monitor battery voltage (cranking detection) and ambient light via a photodiode for automatic headlamp control. OTP EPROM prevents field firmware tampering and reduces per-unit BOM cost in high-volume automotive programs.
Recommended
Security System Sensor Interface
PIR motion detectors, glass-break sensors, and door-magnet interfaces leverage the PIC16C642-10I/SO's two analog comparators to discriminate sensor signals from noise without external op-amps. The Watchdog Timer prevents lockup-induced false alarms, while 176 bytes RAM buffer alarm event queues. Low-power LP oscillator mode with 32 kHz crystal minimizes quiescent current for battery-backed PIRs with multi-year standby life.
Recommended
Remote Control Transmitter
Garage-door openers, ceiling-fan remotes, and consumer IR/RF transmitters use the PIC16C642-10I/SO for protocol encoding (RC5, NEC, proprietary). The 22 I/O can scan 8-button keypads directly, and the USART-less architecture keeps BOM minimal. Sleep mode with Watchdog wake-up draws microamp-level current, enabling coin-cell operation for years. OTP EPROM locks firmware to prevent cloning by competitors.
Recommended
Battery Charger Controller
Lead-acid and NiMH chargers use the PIC16C642-10I/SO to implement CC-CV charge profiles. The two comparators monitor battery voltage and charge current via sense resistors, while the PWM module regulates the buck converter duty cycle. With 128 bytes of EEPROM, calibration constants for chemistry-specific voltage thresholds persist across power cycles. OTP EPROM prevents accidental firmware changes that could damage battery packs.
Recommended
Smart Sensor Node with LED Display
IoT edge nodes with local display feedback (temperature loggers, environmental monitors) pair the PIC16C642-10I/SO with character LCDs and indicator LEDs. Its 22 I/O drive a 16x2 character LCD in 4-bit mode while leaving pins for SPI/I2C sensors. The two comparators handle threshold-based alerting without ADC overhead, and 7 KB OTP holds rich UI state machines. Brown-out reset ensures clean LCD initialization on low-battery conditions.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C642-10I/SO β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C642-04E/SO | PIC16C642-04/SO | PIC16C642T-10I/SO | PIC16C642-10E/SO | PIC16F628-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin SOIC (300-mil) | 28-pin SOIC (300-mil) - same | 28-pin SOIC (300-mil) - same | 28-pin SOIC (300-mil) - same | 28-pin SOIC (300-mil) - same | 28-pin SOIC (300-mil) - same |
| Program Memory | 7 KB OTP EPROM | 7 KB OTP EPROM - same | 7 KB OTP EPROM - same | 7 KB OTP EPROM - same | 7 KB OTP EPROM - same | 3.5 KB Flash (reprogrammable) |
| RAM | 176 bytes | 176 bytes - same | 176 bytes - same | 176 bytes - same | 176 bytes - same | 224 bytes (+27%) |
| Max Clock Speed | 10 MHz | 4 MHz (-60%) | 4 MHz (-60%) | 10 MHz - same | 10 MHz - same | 20 MHz (+100%) |
| I/O Pins | 22 | 22 - same | 22 - same | 22 - same | 22 - same | 16 (-27%) |
| Analog Comparators | 2 | 2 - same | 2 - same | 2 - same | 2 - same | 2 - same |
| USART Module | No | No | No | No | No | Yes (added) |
| Temperature Range | -40C to +85C (Industrial) | -40C to +125C (Extended) | 0C to +70C (Commercial) | -40C to +85C - same | -40C to +125C (Extended) | -40C to +85C - same |
Key Differentiators
- Higher 10 MHz clock speed grade vs 04 MHz variants (vs PIC16C642-04/SO)
- Industrial -40C to +85C temperature range (vs PIC16C642-04/SO)
- Two integrated analog comparators with programmable Vref (vs PIC16C622 family)
Design Notes
Place a 0.1 uF decoupling capacitor within 5 mm of the VDD pin (pin 14) and a bulk 10 uF electrolytic on the same supply rail. The PIC16C642 draws up to 30 mA at full I/O load and 5 V, so a regulator with at least 50 mA headroom (e.g., 7805 or LDO) is recommended. For battery operation, configure the brown-out reset (BOR) at 4.0 V to ensure deterministic shutdown below the MCU's safe VDD minimum.
Select the oscillator mode carefully. RC mode (lowest cost) requires external R/C components with frequency dependent on tolerance. XT mode supports crystals up to 4 MHz. HS mode supports up to 20 MHz at 5 V but draws more current. LP mode with a 32 kHz crystal minimizes quiescent current to ~20 uA for Sleep mode battery designs. Always keep the crystal load capacitors (typically 15-33 pF) close to the OSC1/OSC2 pins to minimize EMI.
For in-circuit debugging, connect MCLR through a 10 kohm pull-up resistor (not directly to VDD) so the debugger can pull MCLR low to enter ICD mode. RB6 and RB7 are shared with the ICD clock/data lines; design them with sufficient isolation (no direct high-current loads) so debugger communication is not disrupted. RB3 is the ICD low-voltage programming entry pin and must NOT be pulled low at power-up in production.
Do not use PORTB internal weak pull-ups on RB0 (INT pin) for wake-up from Sleep if external noise may couple - use an external pull-up. The MCLR pin must NOT be left floating - always tie to VDD through a resistor (typically 10 kohm). The PORTA analog inputs (RA0-RA5) require clearing the PCFG bits in ADCON1 even if the ADC is unused, otherwise the digital input buffers are disabled and the pins read as 0.
Compliance Information
RoHS compliance for PIC16C642-10I/SO is [DATA_NEEDED: RoHS status] - the legacy PIC16C OTP family was launched before strict RoHS deadlines, so individual lots may be RoHS-exempt under 7(c)-I (lead in glass) or fully RoHS-compliant. AEC-Q100 automotive qualification is not applicable for the standard 'I' industrial grade - automotive designs should use the PIC16C642-10E/SO (extended temp) or a PIC16F automotive-grade equivalent.
