PIC16C505T-20/SL - 8-Bit CMOS MCU, 1.5KB OTP, 12 I/O | Microchip
MPN: PIC16C505T-20/SL β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.45 | $2.45 |
| 10 | $2.21 | $22.10 |
| 100 | $1.89 | $189.00 |
| 500 | $1.62 | $810.00 |
| 1,000 | $1.38 | $1,380.00 |
PIC16C505T-20/SL Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU, memory, and programmable I/O peripherals. The PIC16C505 belongs to the PIC16 family of 8-bit RISC microcontrollers, sitting under the broader category of embedded processors and microcontrollers within the Integrated Circuits hierarchy. MCUs execute firmware stored in non-volatile memory (here, One-Time-Programmable EPROM) to read sensors, drive actuators, and communicate with other ICs. The 12-bit instruction word and 33-instruction RISC core yield a typical 2:1 code compression over competing 8-bit architectures, allowing more application functionality within the modest 1.5KB program space.
Key features of the PIC16C505 include a 4-channel 8-bit analog-to-digital converter (ADC), two analog comparators, a watchdog timer, an 8-bit real-time timer/counter with 8-bit prescaler, and an internal oscillator. The 14-pin SOIC footprint exposes 12 general-purpose I/O lines shared with peripheral functions (ADC inputs, comparator inputs, timer clock). Wide operating voltage (2.5V to 5.5V) and commercial temperature range (0C to +70C for the -20 grade) support battery-powered and consumer applications.
Architecturally, the PIC16C505 uses a Harvard RISC core with separate program and data buses, an 8-level deep hardware stack, and direct/indirect addressing modes. The 8-bit ALU operates on data memory organized as general-purpose registers plus special-function registers. A 12-bit instruction word fetches in a single cycle (200ns at 20MHz), with program branches taking two cycles. Power management includes several oscillator modes (RC, LP, XT, HS) and a power-on reset (POR) plus brown-out reset to maintain predictable startup across voltage transients.
Typical applications include small appliance controls, IR remote transmitters, security sensors, lighting controllers, fan and motor PWM drivers, and low-cost consumer toys. The 12 I/O pins and integrated ADC are well-matched to read a button, a thermistor, or a potentiometer while driving a relay, LED, or buzzer without external glue logic.
A critical design consideration for the PIC16C505 family is its OTP program memory - once programmed, the code is permanent and cannot be erased or rewritten. For prototyping and field-upgradable designs, the PIC16F505 (Flash-based, drop-in compatible in 14-pin SOIC) is the recommended alternative, sharing the same instruction set and peripherals but allowing in-circuit reprogramming.
Drop-in alternatives for PIC16C505T-20/SL 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 PIC16C505T-20/SL (same form factor and footprint) β differing in Operating Temperature, Package, Program Memory Size, Series.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16F505T-I/SL
β Drop-Inπ Reference alternative (not in catalog)
PIC16F505-I/SL
β Drop-Inπ Reference alternative (not in catalog)
PIC16C505T-20I/SL
β Drop-Inβ In Stock
$1.18 / Unit
View Datasheet βPIC16C505T-04/SL
β Drop-In β οΈ εζ°εΎ ιͺθ―π Reference alternative (not in catalog)
PIC16C505T-20/SL Maximum Ratings & Electrical Characteristics
| Manufacturer | Microchip Technology |
| Series | PIC 16C |
| Core Processor | PIC |
| Core Size | 8-bit |
| Program Memory Type | OTP (One-Time-Programmable EPROM) |
| Program Memory Size | 1.5 KB (1K x 12) |
| RAM Size | 72 x 8 bytes |
| Number of I/O Pins | 12 |
| Speed (Maximum Clock) | 20 MHz |
| Instruction Cycle Time | 200 ns |
| Number of Instructions | 33 (single-word) |
| Package | 14-SOIC (SL) |
| Mounting Type | Surface Mount |
| Supply Voltage Range | 2.5 V to 5.5 V |
| Operating Temperature | 0 C to +70 C (commercial grade) |
| ADC | 8-bit, 4 channels |
| Comparators | 2 analog comparators |
| Timers | 8-bit timer/counter with 8-bit prescaler + WDT |
| Oscillator Type | Internal RC + external (RC/LP/XT/HS) |
PIC16C505T-20/SL Pin Configuration
| Pin 1 | VDD β Positive supply voltage (2.5V to 5.5V) |
| Pin 2 | OSC1/CLKIN β Oscillator crystal input / external clock input |
| Pin 3 | OSC2/CLKOUT β Oscillator crystal output / clock output (Fosc/4) |
| Pin 4 | MCLR/VPP β Master clear (reset) input / programming voltage |
| Pin 5 | VSS β Ground reference |
| Pin 6 | RC0 β Digital I/O / AN4 analog input |
| Pin 7 | RC1 β Digital I/O / AN5 analog input |
| Pin 8 | RC2 β Digital I/O / AN6 analog input |
| Pin 9 | RC3 β Digital I/O / AN7 analog input |
| Pin 10 | RC4 β Digital I/O / CMP2 comparator output |
| Pin 11 | RC5 β Digital I/O |
| Pin 12 | RB4 β Digital I/O |
| Pin 13 | RB5 β Digital I/O |
| Pin 14 | RB6/RB7 β Digital I/O (RB6/RB7 shared function, see datasheet) |
Typical Applications
PIC16C505T-20/SL is suitable for 6 applications: Small Appliance Control, IR Remote Control Transmitter, LED Lighting and Dimmer Controller, Security and Sensor Modules, Automotive Interior Accessories, Low-Cost Toys and Hobby Electronics.
Small Appliance Control
The PIC16C505T-20/SL fits small appliance controls (coffee makers, toasters, blenders, humidifiers) because its 12 I/O pins can directly drive buttons, LEDs, relays, and a triac without external glue logic. The 4-channel 8-bit ADC reads potentiometers, thermistors (NTC), and water-level sensors for closed-loop control. The 20 MHz clock supports 50/60 Hz zero-cross detection and PWM motor-speed control for fan or pump regulation. OTP memory locks the firmware at production, preventing field tampering and reverse engineering - a security benefit for branded appliances. Compared with discrete logic or ASIC designs, the PIC16C505 reduces BOM count by integrating the CPU, ADC, comparators, watchdog timer, and oscillator into a single 14-pin SOIC.
Recommended
IR Remote Control Transmitter
The PIC16C505T-20/SL is well-suited for IR remote transmitters (TV, STB, audio, AC controllers) thanks to its low cost, 12 I/O for keypad scanning, and 20 MHz clock capable of generating 38 kHz / 40 kHz / 56 kHz carrier frequencies with hardware PWM. The 1.5KB OTP program memory holds compact RC5, NEC, SIRC, or proprietary IR protocol encoders along with keypad matrix decoders. The two analog comparators enable low-battery detection via a resistor divider on the supply rail. OTP ensures the firmware cannot be modified after production, protecting proprietary encoding schemes from cloning. Compared with 8-bit MCUs from other vendors, the PIC16C5x instruction set compresses typical IR encoder code by ~2:1, fitting comfortably in 1.5KB.
Recommended
LED Lighting and Dimmer Controller
The PIC16C505T-20/SL drives LED lighting and dimmer controllers by combining its 4-channel ADC (for sensing ambient light via LDR or color via RGB sensors) with PWM-capable I/O for dimming. At 20 MHz, software PWM can produce 8-bit dimming at 1 kHz update rate, smooth enough for human-eye perception. The integrated watchdog timer prevents controller lockup in long-lifetime installations, while the brown-out reset ensures clean restart after brown-outs. The 14-pin SOIC package fits inside GU10/MR16 bulb form factors. OTP memory locks dimming curves and color-mixing profiles at production. Compared with analog-only dimmer ICs, the PIC16C505 enables programmable dimming curves, fade-in/out, and scene memory.
Recommended
Security and Sensor Modules
The PIC16C505T-20/SL is deployed in security sensor modules (PIR motion detectors, door/window contacts, glass-break detectors, smoke alarm sub-circuits) where low cost and minimal component count are critical. The two analog comparators handle PIR sensor amplification and threshold detection, while the 8-bit ADC reads battery voltage for low-battery reporting. The 12 I/O drive piezo buzzers, status LEDs, and RF/IR transmitter enable pins. Hardware watchdog timer prevents firmware lockup that would render the sensor inoperative. OTP locks the firmware at production to prevent unauthorized modification of detection thresholds or signaling protocols. Compared with ASIC-based sensor controllers, the PIC16C505 allows custom detection logic without NRE charges.
Recommended
Automotive Interior Accessories
Although the PIC16C505T-20/SL is specified for 0C to +70C commercial temperature, it is widely used in non-critical automotive interior accessories (LED accent lighting, USB chargers, fan controllers, seat-position memories for low-end vehicles) where -40C to +85C industrial grade is acceptable via the PIC16C505T-20I/SL variant. The 12 I/O drive indicator LEDs, relays, and pushbutton inputs; the ADC monitors battery voltage and current sense resistors. The internal oscillator eliminates external crystals, reducing BOM cost and PCB area. Compared with automotive-grade MCUs (AEC-Q100 qualified), the C variant offers much lower cost for non-safety accessories.
Recommended
Low-Cost Toys and Hobby Electronics
The PIC16C505T-20/SL powers low-cost toys, educational kits, and hobby electronics where sub-$2 BOM cost is essential. With 33 single-word instructions and 200 ns execution, beginners can learn RISC assembly quickly using Microchip's free MPLAB X IDE and MPASM assembler. The 14-pin SOIC fits on breadboards (with SOIC-to-DIP adapter) and standard perfboards. Applications include line-following robots, electronic dice, sound-effect generators, model train controllers, and programmable LED cubes. Compared with modern ARM Cortex-M0+ alternatives, the PIC16C505 retains a niche for educational and hobbyist users due to its ultra-low cost, simple toolchain, and well-documented baseline PIC architecture.
Recommended
Recommended Products Summary
Engineering reference data for PIC16C505T-20/SL β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F505T-I/SL | PIC16F505-I/SL | PIC16C505T-20I/SL | PIC16C505T-04/SL |
|---|---|---|---|---|---|
| Package | 14-SOIC (SL) | 14-SOIC (SL) - same | 14-SOIC (SL) - same | 14-SOIC (SL) - same | 14-SOIC (SL) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory Type | OTP (1.5 KB) | Flash (1.5 KB) | Flash (1.5 KB) | OTP (1.5 KB) | OTP (1.5 KB) |
| Program Memory Size | 1.5 KB | 1.5 KB | 1.5 KB | 1.5 KB | 1.5 KB |
| Max Clock Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 4 MHz |
| RAM Size | 72 bytes | 72 bytes | 72 bytes | 72 bytes | 72 bytes |
| Number of I/O | 12 | 12 | 12 | 12 | 12 |
| Operating Temperature | 0 C to +70 C (commercial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | 0 C to +70 C (commercial) |
| ADC | 8-bit, 4-ch | 8-bit, 4-ch | 8-bit, 4-ch | 8-bit, 4-ch | 8-bit, 4-ch |
| Reprogrammable | No (OTP) | Yes (Flash) | Yes (Flash) | No (OTP) | No (OTP) |
Key Differentiators
- OTP memory locks firmware permanently (vs PIC16F505T-I/SL)
- Industrial temperature grade variant available in same package (vs PIC16C505T-20/SL (commercial 0C to +70C))
- 33-instruction RISC core yields 2:1 code compression (vs PIC16C54 (legacy 12-bit OTP MCU))
- 20 MHz instruction execution supports real-time PWM and serial (vs PIC16C505T-04/SL (4 MHz variant))
Design Notes
The PIC16C505T-20/SL uses OTP (One-Time-Programmable) program memory. Once programmed, the firmware is permanent and cannot be erased or rewritten. For prototyping, design validation, or any product requiring firmware updates in the field, choose the PIC16F505 (Flash) variant instead. Programming requires Microchip programmers (PICkit 3/4, ICD) or gang programmers, and verification of firmware must be completed before production programming because there is no second chance.
The PIC16C505T-20/SL accepts 2.5V to 5.5V supply. Place a 100 nF decoupling capacitor as close as possible to the VDD pin (pin 1), plus a bulk 10 uF tantalum or aluminum electrolytic capacitor on the supply rail if driving heavy loads. For battery-powered designs using the internal RC oscillator, expect typically 1-2 mA active current at 20 MHz and 5V. Use Sleep mode and the watchdog timer to reduce average current in duty-cycled sensor applications.
Place the MCLR/VPP pin (pin 4) decoupling capacitor (typically 10-100 nF) close to the pin if used in external reset mode. Keep the 14-pin SOIC trace lengths short, especially OSC1/OSC2 traces if a crystal is used. Avoid routing high-current switching signals (relay drivers, triac controls) near the oscillator traces or analog ADC inputs to prevent injection of switching noise into the ADC or clock reference. The exposed copper pad on the SOIC bottom is typically not connected to VSS for this package.
Configuration bits (fuses) must be set correctly during programming: oscillator selection (internal RC vs LP/XT/HS crystal), watchdog timer enable, power-up timer, brown-out detect, and code protection. Incorrect configuration bits are a common cause of apparent 'dead' PICs - the device may simply be in a state where the oscillator is not running or MCLR is held low. Always read back configuration words after programming and verify before depanel.
Compliance Information
RoHS and REACH status not explicitly stated in provided data. Lead-free per Microchip manufacturing standards. Not AEC-Q100 qualified - select automotive-grade baseline PIC variants for AEC-Q100 applications. Conflict minerals statement per Microchip corporate compliance policy.
