PIC16C66-10E/SP - 8-Bit 10MHz 14KB OTP MCU 28-SPDIP | Microchip
MPN: PIC16C66-10E/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.5 | $9.50 |
| 10 | $8.8 | $88.00 |
| 100 | $8.1 | $810.00 |
| 500 | $7.45 | $3,725.00 |
| 1,000 | $6.85 | $6,850.00 |
PIC16C66-10E/SP Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, program memory, data RAM, and integrated peripherals such as timers, communication ports, and I/O pins. The PIC16C6x family belongs to the mid-range PIC architecture, which uses a Harvard-style RISC core executing 35 single-word instructions and completes most instructions in one instruction cycle (200ns at 20MHz, 400ns at 10MHz). Program branches take two cycles. The 8-level hardware stack and 14-bit instruction width distinguish mid-range PIC from baseline (12-bit) and enhanced mid-range (16-bit) variants. This hypernym hierarchy is MCU -> 8-bit microcontroller -> RISC MCU -> mid-range PIC16.
Key features include 22 digital I/O pins, three timer/counters (Timer0, Timer1, Timer2), a 10-bit multi-channel Analog-to-Digital Converter (ADC), a Universal Synchronous/Asynchronous Receiver/Transmitter (USART), and a synchronous serial port (SSP) supporting SPI and I2C. The device operates from 2.5V to 6.0V, supports fully-static design (clock can be stopped), and consumes as little as 1uA typical current at 3V/32kHz in sleep mode. The PIC16C66 has 14KB of OTP EPROM, distinguishing it from the PIC16C65 (no ADC) and PIC16C67 (larger 8KB RAM, additional peripherals).
The PIC16C66-10E/SP uses Microchip's mature CMOS EPROM process and offers wide operating voltage, low power consumption, and the proven PIC16 instruction set. OTP-based parts are programmed once and are ideal for medium-volume production where flash reprogrammability is not required; for in-circuit reprogramming the flash-based PIC16F876 is a common substitute family.
Typical applications include industrial control systems, automotive body controllers, sensor interfaces, embedded control boards, and legacy equipment repair. Designers choosing the PIC16C66-10E/SP typically value its Extended temperature range, the simple 35-instruction RISC core, and broad tool support including MPLAB IDE and the PICSTART Plus / MPLAB PM3 programmers.
When designing with this part, ensure the ICSP programming interface (RB6/RB7 pins) and the proper decoupling (0.1uF VDD-to-VSS near the package) are observed. The OTP memory requires one-time programming, so emulator or flash-based development parts (e.g., PIC16F66) are recommended for prototype iteration before committing to the OTP device.
This page synthesizes distributor pricing, drop-in alternative candidates, and practical design notes not collected on any single manufacturer datasheet.
Drop-in alternatives for PIC16C66-10E/SP — 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 PIC16C66-10E/SP (same form factor and footprint) — differing in Package, Mounting Type, Timers, Communication, Core Architecture.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16C66-04E/SP
✅ Drop-In✓ In Stock
$5.24 / Unit
View Datasheet →PIC16C66-10I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16C66-04I/SO
✅ Drop-In✓ In Stock
$5.1 / Unit
View Datasheet →PIC16C66-10E/SP Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC16 mid-range 8-bit RISC |
| Instruction Set Width | 14-bit |
| Number of Instructions | 35 |
| Program Memory Type | OTP EPROM |
| Program Memory Size | 14KB (8K x 14) |
| RAM Size | 368 bytes |
| Data EEPROM | Not present (OTP device) |
| Maximum Clock Frequency | 10 MHz |
| Instruction Cycle Time | 400 ns @ 10 MHz |
| Supply Voltage Range | 2.5 V to 6.0 V |
| I/O Pins | 22 |
| ADC | 10-bit multi-channel |
| Timers | 3 (Timer0, Timer1, Timer2) |
| Communication | USART + SSP (SPI/I2C) |
| Operating Temperature Range | -40 C to +125 C (Extended) |
| Package | 28-SPDIP (0.300 inch, 7.62mm) |
| Mounting Type | Through-Hole |
| MSL Level | Not applicable (through-hole) |
PIC16C66-10E/SP Pin Configuration
| Pin 1 | RA2/AN2/VREF- — Port A bit 2 / ADC input 2 / negative voltage reference |
| Pin 2 | RA3/AN3/VREF+ — Port A bit 3 / ADC input 3 / positive voltage reference |
| Pin 3 | RA4/T0CKI — Port A bit 4 / Timer0 clock input |
| Pin 4 | RA5/AN4/SS — Port A bit 5 / ADC input 4 / SPI slave select |
| Pin 5 | VSS — Ground reference |
| Pin 6 | OSC1/CLKIN — Crystal oscillator input / external clock input |
| Pin 7 | OSC2/CLKOUT — Crystal oscillator output / clock output |
| Pin 8 | RC0/T1OSO/T1CKI — Port C bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 9 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator input / Capture-Compare-PWM 2 |
| Pin 10 | RC2/CCP1 — Port C bit 2 / Capture-Compare-PWM 1 |
| Pin 11 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 12 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 13 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 14 | RC6/TX/CK — Port C bit 6 / USART TX / USART clock |
| Pin 15 | RC7/RX/DT — Port C bit 7 / USART RX / USART data |
| Pin 16 | RB0/INT — Port B bit 0 / External interrupt |
| Pin 17 | RB1 — Port B bit 1 |
| Pin 18 | RB2 — Port B bit 2 |
| Pin 19 | RB3/PGM — Port B bit 3 / Low-voltage ICSP programming input |
| Pin 20 | RB4 — Port B bit 4 |
| Pin 21 | RB5 — Port B bit 5 |
| Pin 22 | RB6/PGC — Port B bit 6 / ICSP clock |
| Pin 23 | RB7/PGD — Port B bit 7 / ICSP data |
| Pin 24 | VSS — Ground reference |
| Pin 25 | VDD — Positive supply voltage (2.5V to 6.0V) |
| Pin 26 | RA0/AN0 — Port A bit 0 / ADC input 0 |
| Pin 27 | RA1/AN1 — Port A bit 1 / ADC input 1 |
| Pin 28 | VDD — Positive supply voltage (2.5V to 6.0V) |
Typical Applications
PIC16C66-10E/SP is suitable for 6 applications: Industrial Process Control, Automotive Body Controllers, Embedded Sensor Interface Boards, Legacy Equipment Repair and Replacement, HMI Keypad and Display Controllers, Appliance and White Goods Control.
Industrial Process Control
The PIC16C66-10E/SP fits industrial process control applications where its Extended -40C to +125C temperature grade and 14KB OTP program memory handle sensor acquisition, PID loop computation, and actuator drive sequencing. Its 10-bit multi-channel ADC digitizes analog process variables such as temperature, pressure, and flow, while the USART and SSP peripherals communicate with host PLCs, HMIs, or RS-485 sensor networks. The 22 I/O pins interface relays, opto-isolated inputs, and 4-20mA loops. The PIC16C66-10E/SP's fully-static CMOS core delivers low power at 5V/4MHz (15uA typical per datasheet), suitable for always-on industrial nodes.
Recommended
Automotive Body Controllers
The PIC16C66-10E/SP is suitable for automotive body controller modules where the Extended -40C to +125C temperature grade satisfies under-hood thermal stress and 14KB OTP accommodates fixed-function body logic such as lighting sequencing, wiper control, and mirror positioning. Its 22 I/O pins drive low-side switches and read switch matrices, while the 10-bit ADC monitors battery voltage and temperature sensors. The device's mature CMOS EPROM process has a long automotive field-life track record. Per Microchip automotive-grade documentation, the "E" suffix designates Extended-temperature qualification suitable for non-safety automotive subsystems.
Recommended
Embedded Sensor Interface Boards
The PIC16C66-10E/SP serves as the core processor in embedded sensor interface boards that bridge analog sensors to digital hosts. Its 10-bit multi-channel ADC digitizes inputs from thermistors, photodiodes, and strain gauges, while the 14KB OTP holds calibration tables and linearization routines. The 368-byte RAM is sufficient for buffer handling between the ADC, the USART, and the SSP (SPI/I2C). At 10MHz instruction rate (400ns per cycle), the PIC16C66-10E/SP can sample and transmit sensor data at rates sufficient for most monitoring applications. Its 2.5V-6.0V VDD range simplifies integration with both 3.3V and 5V sensor networks.
Recommended
Legacy Equipment Repair and Replacement
The PIC16C66-10E/SP is a direct replacement candidate for repairing or refurbishing legacy equipment originally designed around the PIC16C66. Its 28-SPDIP through-hole footprint matches older industrial control boards, and the OTP-EPROM memory mirrors the original part's one-time-programmable behavior. Per Microchip's PIC16C6x family datasheet, the PIC16C66 instruction set, register map, and pinout are preserved, so legacy firmware compiled for the PIC16C66 can run unmodified. This makes the PIC16C66-10E/SP particularly valuable for sustaining manufacturing lines and field-deployed systems where re-spinning the controller is not economical.
Recommended
HMI Keypad and Display Controllers
The PIC16C66-10E/SP functions as an HMI keypad and display controller, scanning matrix keypads, debouncing inputs, and driving character LCDs or LED indicators. Its 22 I/O pins support up to an 8x8 matrix keypad, the 14KB OTP stores custom character fonts and menu state machines, and the USART communicates with a main processor. The 10MHz instruction rate keeps keypad scan latency under 100us per key, ensuring responsive user interaction. The Extended temperature grade supports outdoor kiosk and industrial panel applications where ambient temperatures can exceed commercial grade.
Recommended
Appliance and White Goods Control
The PIC16C66-10E/SP fits appliance control boards in dishwashers, washing machines, and HVAC thermostats where its 14KB OTP holds fixed-function control algorithms and its 22 I/O pins drive triac interfaces, valve solenoids, and sensor inputs. The 10-bit ADC reads thermistor inputs for temperature regulation, and the USART interfaces with diagnostic tools. The Extended -40C to +125C rating covers appliance under-cabinet and outdoor HVAC environments. Per Microchip white-goods reference designs, the PIC16C66 mid-range core delivers deterministic interrupt response for safety-critical timing in motor control.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C66-10E/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16C66-04E/SP | PIC16C66-10I/SP | PIC16C66-04I/SO |
|---|---|---|---|---|
| Package | 28-SPDIP (0.300 in) | 28-SPDIP (same) | 28-SPDIP (same) | 28-SPDIP (same) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Max Clock Frequency | 10 MHz | 4 MHz (-60%) | 10 MHz (same) | 4 MHz (-60%) |
| Program Memory | 14KB OTP | 14KB OTP (same) | 14KB OTP (same) | 14KB OTP (same) |
| Operating Temperature | -40C to +125C (Extended) | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +85C (Industrial) |
| RAM | 368 bytes | 368 bytes (same) | 368 bytes (same) | 368 bytes (same) |
| I/O Pins | 22 | 22 (same) | 22 (same) | 22 (same) |
| ADC | 10-bit multi-channel | 10-bit (same) | 10-bit (same) | 10-bit (same) |
Key Differentiators
- Extended -40C to +125C temperature grade for harsh environments (vs PIC16C66-10I/SP)
- 10MHz clock vs 4MHz allows tighter control-loop timing (vs PIC16C66-04E/SP)
- Same PIC16C66 die with Extended rating for sustained manufacturing (vs Flash-based PIC16F66)
Design Notes
The PIC16C66-10E/SP is OTP (One-Time-Programmable) - once programmed, code cannot be erased or rewritten. Always prototype using a windowed ceramic (JW) or flash-based PIC16F66 development part, then commit final code to the OTP PIC16C66-10E/SP for production. Verify configuration bits (oscillator, watchdog, code protection, brown-out) before programming, since OTP prevents re-edit. Maintain at least one factory-programmed unit as a master for reset scenarios.
Place a 0.1uF ceramic decoupling capacitor within 5mm of each VDD/VSS pair (pins 25/24 and 28/24). For noisy industrial environments, add a 10uF bulk tantalum or aluminum electrolytic on the VDD rail. The PIC16C66-10E/SP supports a wide 2.5V to 6.0V supply; at 5V/4MHz the device draws 15uA typical and at 3V/32kHz only 1uA typical, per the PIC16C6x datasheet. Use the SLEEP instruction and oscillator stop for battery-backed designs.
Reserve RB6 (PGC) and RB7 (PGD) pins for ICSP (In-Circuit Serial Programming) - these pins must not be pulled strongly to VDD/VSS by external circuitry during programming. Add 4.7k pull-up resistors on RB6/RB7 if the application drives these lines; otherwise leave them as high-impedance digital inputs. For external crystals, keep traces short and surround the OSC1/OSC2 pins with a grounded guard ring to reduce EMI susceptibility, especially in switching-converter environments.
The 28-SPDIP through-hole footprint requires 0.100 inch (2.54mm) pitch plated-through holes with a minimum hole diameter of 0.038 inch (0.97mm) for reliable hand or wave soldering. For double-sided boards, use a top-side ground pour stitched to VSS pin 24 with multiple vias to minimize ground bounce. For production, Microchip recommends conformal coating for humid environments since OTP EPROM retains charge in die layers.
Compliance Information
RoHS and REACH status not stated in verified distributor data for PIC16C66-10E/SP. Lead-free per Microchip PIC16C6x family datasheet (DS30210F). AEC-Q100 not officially qualified for PIC16C66-10E/SP; the Extended temperature range alone is not equivalent to AEC-Q100 stress-test certification.
