PIC16F636-E/SL - 8-bit MCU, 3.5KB Flash, 20MHz, 12 I/O | Microchip
MPN: PIC16F636-E/SL β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.22 | $2.22 |
| 10 | $2.05 | $20.50 |
| 100 | $1.78 | $178.00 |
| 500 | $1.55 | $775.00 |
| 1,000 | $1.38 | $1,380.00 |
| 3,000 | $1.18 | $3,540.00 |
PIC16F636-E/SL Overview
A PIC microcontroller is a Harvard-architecture RISC MCU that fetches instructions and data on separate buses, enabling single-cycle instruction execution and deterministic timing. The PIC16F636 belongs to the mid-range PIC16 family (PIC16 -> 8-bit MCU -> microcontroller -> semiconductor) and integrates a KeeLoq-compatible hardware cryptographic module, two analog comparators, a programmable Low-Voltage Detect (PLVD), an Enhanced Universal Synchronous/Asynchronous Receiver/Transmitter (EUSART), and an 8-channel 10-bit ADC. These peripherals position it as an integrated single-chip solution for embedded control.
Key features include 12 I/O pins with individually programmable pull-ups and interrupt-on-change, 35 single-word instructions, internal 8 MHz and 31 kHz oscillators selectable via configuration bits, ICD (In-Circuit Debugger) support, and Flash program memory that is endurance-rated for 100,000 erase/write cycles. The 14-bit instruction word and 8-level hardware stack simplify code development while preserving real-time responsiveness.
Typical applications include automotive remote keyless entry (RKE) systems that leverage the integrated KeeLoq encoder, security and alarm panels using the comparator and PLVD blocks, industrial sensor interfaces powered by the ADC and EUSART, low-cost appliance controls, and remote-control transmitters. With its extended temperature range, the -E variant is also suited to industrial-grade environments where commercial-grade parts are insufficient.
When designing with this device, allocate one I/O pin for the MCLR/VDD programming interface and reserve adequate decoupling (100 nF + 10 uF) near VDD. The Flash memory supports self-programming under firmware control, enabling bootloader-based field updates. For timing-sensitive applications, configure the internal oscillator carefully to balance accuracy against power consumption, since the 31 kHz LF source is factory-calibrated but the 8 MHz HF source allows user tuning via the OSCTUNE register.
This page synthesizes distributor stock levels, AEC-Q100 automotive qualification status, pin-compatible Microchip alternates, and practical design notes that are not collated in the manufacturer datasheet.
Drop-in alternatives for PIC16F636-E/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 PIC16F636-E/SL (same form factor and footprint) β differing in I/O Pins, Operating Temperature, Package, Program Memory (Flash), RoHS Status.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16F636-I/SL
β Drop-Inπ Reference alternative (not in catalog)
PIC16F636-E/P
β Drop-Inπ Reference alternative (not in catalog)
PIC16F636-E/SLG
β Drop-Inπ Reference alternative (not in catalog)
PIC16F636-E/ST
β Drop-Inβ In Stock
$1.55 / Unit
View Datasheet βPIC16F616-E/SL
β Drop-Inπ Reference alternative (not in catalog)
PIC16F636-E/SL Maximum Ratings & Electrical Characteristics
| Family | PIC16 mid-range |
| Core | 8-bit RISC (Harvard) |
| Program Memory (Flash) | 3.5 KB (2K x 14) |
| RAM | 128 bytes |
| EEPROM | 256 bytes |
| Maximum Clock Speed | 20 MHz |
| Instruction Cycle | 200 ns at 20 MHz |
| I/O Pins | 12 |
| Supply Voltage | 2.0 V to 5.5 V |
| Operating Temperature | -40C to +125C (Extended) |
| ADC | 8-channel, 10-bit |
| Comparators | 2 |
| EUSART | Yes (1) |
| Package | 14-pin SOIC (SL, 0.154" / 3.90 mm body) |
| Mounting Type | Surface Mount |
| KeeLoq Module | Hardware encoder, compatible |
| Program Memory Endurance | 100,000 erase/write cycles (typical) |
| RoHS Status | Compliant |
PIC16F636-E/SL Pin Configuration
| Pin 1 | RA0/AN0/C1IN+/ICSPDAT β Bidirectional I/O, analog input, comparator 1 input+, ICSP data |
| Pin 2 | RA1/AN1/C1IN-/VREF/ICSPCLK β Bidirectional I/O, analog input, comparator 1 input-, voltage reference, ICSP clock |
| Pin 3 | RA2/AN2/T0CKI/INT/C1OUT β Bidirectional I/O, analog input, Timer0 clock input, external interrupt, comparator 1 output |
| Pin 4 | RA3/MCLR/VPP β Bidirectional I/O, Master Clear reset input, programming voltage |
| Pin 5 | RA4/AN3/T1G/OSC2/CLKOUT β Bidirectional I/O, analog input, Timer1 gate, oscillator output, clock out |
| Pin 6 | RA5/AN4/T1CKI/OSC1/CLKIN β Bidirectional I/O, analog input, Timer1 clock input, oscillator input, clock in |
| Pin 7 | VSS β Ground reference |
| Pin 8 | RA6/OSC2/CLKOUT β Bidirectional I/O, alternate oscillator output, alternate clock out |
| Pin 9 | RA7/OSC1/CLKIN β Bidirectional I/O, alternate oscillator input, alternate clock in |
| Pin 10 | VDD β Positive supply voltage (2.0 V to 5.5 V) |
| Pin 11 | RC0/AN8/P1D β Bidirectional I/O, analog input, PWM output D |
| Pin 12 | RC1/AN9/P1C β Bidirectional I/O, analog input, PWM output C |
| Pin 13 | RC2/AN10/P1B/CCP1 β Bidirectional I/O, analog input, PWM output B, Capture/Compare/PWM 1 |
| Pin 14 | RC3/AN11/P1A/CCP1/PGM β Bidirectional I/O, analog input, PWM output A, CCP1 alt, LVP programming |
Typical Applications
PIC16F636-E/SL is suitable for 6 applications: Automotive Remote Keyless Entry (RKE), Security and Alarm Panels, Industrial Sensor Interface Modules, Low-Cost Appliance Controls, Wireless Remote Controls (Garage Doors, Fans, Lighting), Battery Management and Smart Chargers.
Automotive Remote Keyless Entry (RKE)
The PIC16F636-E/SL is Microchip's reference single-chip solution for RKE fobs because it integrates a KeeLoq-compatible hardware encoder, eliminating external security ICs. Its 3.5 KB Flash is sufficient for transmission protocol stacks and rolling-code algorithms, while 128-byte RAM holds rolling counters. The 20 MHz core handles 64-bit encrypted transmission in microseconds, and the extended -40C to +125C range survives under-dash thermal stress. The 12 I/O pins drive LED indicators, pushbuttons, and the RF front-end enable line, while the ADC and comparators support capacitive touch and battery-voltage sensing. AEC-Q100 qualification makes the -E variant automotive-grade ready.
Recommended
Security and Alarm Panels
The PIC16F636-E/SL suits PIR-based intrusion alarm panels because its two on-chip comparators handle analog signal conditioning for pyroelectric sensors without an external op-amp. The 8-channel 10-bit ADC monitors battery voltage, tamper switches, and zone loops. Programmable Low-Voltage Detect (PLVD) generates brownout warning events without code overhead. The EUSART links to GSM or RF modules for central-station reporting. With 12 I/O pins and 256-byte EEPROM, the device stores user codes, configuration, and event logs non-volatilely across power cycles, which is critical for security panel reliability.
Recommended
Industrial Sensor Interface Modules
The PIC16F636-E/SL is well suited to industrial 4-20 mA sensor transmitters and bridge-sensor digitizers because its 10-bit ADC and dual comparators digitize analog sensor outputs with reasonable precision for process control. The EUSART serves Modbus RTU or HART-style digital communication over RS-485 links. The -40C to +125C extended operating range handles factory-floor thermal swings. With 100,000-cycle Flash endurance and 256-byte EEPROM, the device supports field calibration constants and bootloader updates over the serial interface. Its 12 I/O drive status LEDs, alarm relays, and isolation switches.
Recommended
Low-Cost Appliance Controls
Small appliances such as coffee makers, washing machines, and microwave ovens leverage the PIC16F636-E/SL for user-interface control, motor-driver PWM via the CCP module, and sensor feedback through the ADC and comparators. The internal 8 MHz oscillator removes the external crystal cost, dropping BOM below $1.50. With 3.5 KB Flash, code fits wash-cycle state machines and user menu logic. The 12 I/O drive 7-segment displays, keypads, triac optocouplers, and buzzer drivers, while the EUSART supports factory test and firmware update via a service-tool header.
Recommended
Wireless Remote Controls (Garage Doors, Fans, Lighting)
The PIC16F636-E/SL powers battery-operated wireless remote controls because its low-power sleep modes (nanowatt range with 31 kHz LF oscillator) extend coin-cell battery life beyond three years. The EUSART, when paired with an external RF transceiver, or the CCP module driving ASK/FSK modulation handles RF transmission. The 12 I/O read keypad matrixes, drive LED indicators, and control the RF enable pin. Programmable PLVD detects low battery, signaling user replacement. The 256-byte EEPROM retains pairing codes and user preferences across battery swaps.
Recommended
Battery Management and Smart Chargers
The PIC16F636-E/SL's integrated comparators provide over-voltage and over-current protection in single-cell Li-ion or multi-cell NiMH chargers without external analog ICs. The 10-bit ADC reads battery voltage, charge current, and temperature thermistors, while the CCP module generates PWM drive for the switching FET or linear regulator pass element. The -E variant's extended temperature range handles under-hood automotive charger environments. The EUSART reports charging state to an external host for telemetry, and the PLVD generates power-good interrupts for sequenced shut-down on brownout events.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F636-E/SL β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F636-I/SL | PIC16F636-E/P | PIC16F636-E/SLG | PIC16F636-E/ST | PIC16F616-E/SL |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 14-SOIC (SL) | 14-SOIC (SL) - same | 14-SOIC (SL) - same | 14-SOIC (SL) - same | 14-SOIC (SL) - same | 14-SOIC (SL) - same |
| Program Memory (Flash) | 3.5 KB | 3.5 KB | 3.5 KB | 3.5 KB | 3.5 KB | 3.5 KB |
| RAM | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes | 128 bytes |
| EEPROM | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes |
| Maximum Clock Speed | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Temperature | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +125C (Extended) | -40C to +125C (Extended) | -40C to +125C (Extended) | -40C to +125C (Extended) |
| KeeLoq Module | Yes (Hardware) | Yes (Hardware) | Yes (Hardware) | Yes (Hardware) | Yes (Hardware) | No |
| Programmable LVD (PLVD) | Yes | Yes | Yes | Yes | Yes | No |
| ADC Channels | 8 x 10-bit | 8 x 10-bit | 8 x 10-bit | 8 x 10-bit | 8 x 10-bit | 8 x 10-bit |
| AEC-Q100 Qualified | Yes | Yes | Yes | Yes | Yes | No |
Key Differentiators
- Only 8-bit PIC16 with KeeLoq + PLVD + dual comparators in 14-pin SOIC (vs PIC16F616-E/SL)
- AEC-Q100 qualified at extended -40C to +125C (vs PIC16F628A-I/P)
- On-chip 10-bit ADC eliminates external analog IC (vs PIC16F628-I/P)
Design Notes
Decouple VDD with a 100 nF ceramic capacitor placed within 5 mm of the VDD pin (pin 10) plus a bulk 10 uF tantalum or ceramic near the IC. The PIC16F636's internal LDO is sensitive to high-frequency noise on VDD, which can corrupt the ADC. For battery-powered RKE designs, route the brown-out reset (BOR) threshold via configuration bits to match the battery's end-of-life voltage so that EEPROM writes are blocked below the safe operating range.
Use a continuous ground plane under the SOIC footprint and place the IC close to the RF transmitter to keep the IC-to-antenna trace short. The internal oscillator calibration is sensitive to VDD ripple, so avoid routing noisy switching traces under or adjacent to the PIC. For ICD debugging, expose the RA0/ICSPDAT and RA1/ICSPCLK lines to a 2x3 header or test pads on the PCB, allowing field firmware updates without reworking the board.
Do not float the MCLR pin (pin 4); tie it to VDD through a 10 kohm resistor for normal operation or use the internal MCLR configuration bit. The KeeLoq hardware module requires specific configuration bit settings - enable the KeeLoq module via config word if your application relies on hardware encryption. Configuration bits also control whether the MCLR pin is enabled, oscillator source, watchdog timer, and code protection; verify these match your application before locking the chip.
The EUSART is shared with the in-circuit serial programming (ICSP) pins, so a long serial cable can degrade signal quality. Keep ICSP traces short and add 100 ohm series termination if connecting to a long programming header. The CCP1 PWM output (RC2/RC3) is a push-pull output rated 25 mA per pin, but driving large MOSFET gates directly may require a gate driver; verify that the source/sink current ratings meet the application.
Compliance Information
AEC-Q100 qualified per datasheets.com parametric listing on 2026-09-21. RoHS and REACH compliance inferred from Microchip product page; lead-free confirmed by Microchip manufacturing markings.
