PIC16F688-I/SL - 8-Bit 20MHz 7KB Flash MCU | Microchip
MPN: PIC16F688-I/SL β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.94 | $1.94 |
| 10 | $1.72 | $17.20 |
| 100 | $1.45 | $145.00 |
| 500 | $1.21 | $605.00 |
| 1,000 | $1.12 | $1,120.00 |
PIC16F688-I/SL Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, non-volatile program memory, working RAM, and programmable I/O peripherals. The PIC16F family belongs to the broader 8-bit PIC microcontroller hierarchy (PIC10/12/16/18 -> mid-range 14-bit instruction set -> microcontroller -> embedded computing IC), making PIC16F688-I/SL a typical low-pin-count (14-pin) general-purpose embedded controller. It targets cost-sensitive designs that need more peripherals than 8-pin MCUs but want a smaller footprint than 28-pin or 40-pin PICs.
Key features include a wide 2.0-5.5V operating range suitable for both 3.3V and 5V systems, on-chip EEPROM for non-volatile data storage without external serial memory, and Microchip's nanoWatt power management that offers multiple sleep modes with wake-up sources for battery-powered applications. The integrated 10-bit ADC and analog comparator reduce BOM cost in sensor-interface designs, while the USART enables asynchronous serial communication for wired connectivity.
The PIC16F688-I/SL uses Microchip's mid-range 14-bit instruction set with only 35 single-word instructions, providing an easy-to-learn architecture with deterministic 200 ns instruction execution at 20 MHz. Its oscillator design supports internal 8 MHz and 31 kHz oscillators plus external crystal/HS modes, allowing designers to minimize external component count. The architecture is well suited to real-time control loops where predictable interrupt latency and deterministic timing matter.
Typical applications include consumer appliance control, battery chargers, sensor signal conditioning, lighting control, and small industrial automation modules. In each case, the PIC16F688-I/SL delivers a balance of program space, peripheral mix, and I/O count for compact embedded designs.
When designing with this device, reserve RA0/RA1/RA3 for the MCLR/programming pins and respect the 5.5V absolute maximum supply voltage. Use MPLAB X IDE with XC8 compiler for firmware development; Microchip provides the PICkit 3 or PICkit 5 programmer for in-circuit debug and flash programming.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16F688-I/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 PIC16F688-I/SL (same form factor and footprint) β differing in Package, Timers, ADC, Core Architecture, Operating Temperature.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16F688-E/SL
β Drop-Inβ In Stock
$1.05 / Unit
View Datasheet βPIC16F688T-I/SL
β Drop-Inπ Reference alternative (not in catalog)
PIC16F688-I/SL Maximum Ratings & Electrical Characteristics
| Device Family | PIC16F |
| Architecture | 8-bit, mid-range 14-bit instruction set |
| Maximum Clock Frequency | 20 MHz |
| Instruction Cycle | 200 ns |
| Program Memory (Flash) | 7 KB (4K x 14 words) |
| Data EEPROM | 256 bytes |
| Data SRAM | 256 bytes |
| Operating Voltage Range | 2.0 V to 5.5 V |
| I/O Pins | 12 |
| ADC | 10-bit, up to 8 channels |
| Package | 14-SOIC (SL), 3.90 mm body width |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (Industrial) |
| Pin/Package Code | SL = 14-SOIC |
| Instruction Set | 35 single-word instructions |
| USART | Yes (Enhanced USART) |
| ECCP Module | Yes (Enhanced Capture/Compare/PWM) |
| Comparators | Yes, analog comparator |
| Timers | Timer0, Timer1, Timer2 |
| Oscillator Modes | Internal 8 MHz, Internal 31 kHz, External crystal (HS/XT), RC |
| nanoWatt Power Management | Yes |
| MSL Level | MSL1 (per JEDEC J-STD-020) |
| RoHS Status | Compliant |
PIC16F688-I/SL Pin Configuration
| Pin 1 | VDD β Positive supply voltage (2.0-5.5V) |
| Pin 2 | RA5/T1CKI/OSC1/CLKIN β Digital I/O / Timer1 clock input / oscillator input |
| Pin 3 | RA4/AN3/T1G/OSC2/CLKOUT β Digital I/O / ADC input / Timer1 gate / oscillator output |
| Pin 4 | RA3/MCLR/VPP β Digital I/O / Master Clear reset (active low) / programming voltage |
| Pin 5 | RC5 β Digital I/O (PORTC bit 5) |
| Pin 6 | RC4 β Digital I/O (PORTC bit 4) |
| Pin 7 | RC3/AN7 β Digital I/O / ADC input channel 7 |
| Pin 8 | RC2/AN6 β Digital I/O / ADC input channel 6 |
| Pin 9 | RC1/AN5 β Digital I/O / ADC input channel 5 |
| Pin 10 | RC0/AN4 β Digital I/O / ADC input channel 4 |
| Pin 11 | RA2/AN2 β Digital I/O / ADC input channel 2 |
| Pin 12 | RA1/AN1/ICSPCLK β Digital I/O / ADC input channel 1 / ICSP clock |
| Pin 13 | RA0/AN0/ICSPDAT β Digital I/O / ADC input channel 0 / ICSP data |
| Pin 14 | VSS β Ground reference |
Typical Applications
PIC16F688-I/SL is suitable for 6 applications: Consumer Appliance Control, Battery Charger Control, Sensor Signal Conditioning, Lighting Control (LED Driver MCU), Small Industrial Automation Modules, Remote Control / IR Transmitter.
Consumer Appliance Control
The PIC16F688-I/SL fits consumer appliance control boards such as coffee makers, microwave ovens, and washing-machine sub-modules where its 7KB flash holds the user-interface and sensor-fusion state machine, the 10-bit ADC reads NTC temperature sensors and rotary-encoder pots, and the 2.0-5.5V supply tolerance lets it share a regulated rail with 3.3V display logic. The 12 I/O pins drive seven-segment LEDs, button matrices, and triac/relay drivers directly, while ECCP generates the zero-crossing timing for triac-based heater power control. NanoWatt sleep modes drop standby current below 1 uA to meet Energy Star standby budgets.
Recommended
Battery Charger Control
Smart battery chargers for Li-ion, NiMH, and lead-acid chemistries use the PIC16F688-I/SL as the charge-state controller. Its 10-bit ADC reads battery voltage, charge current (via a sense resistor and op-amp), and cell temperature (via NTC), while the 7KB flash holds the CC-CV state machine and termination logic. The ECCP module generates PWM for the buck converter switching node, and the USART enables SMBus/I2C communication with fuel-gauge ICs or external EEPROM. Wide 2.0-5.5V operation lets the same firmware run on 1S Li-ion (4.2V max) and 5V USB supplies.
Recommended
Sensor Signal Conditioning
Industrial sensor-interface modules leverage the PIC16F688-I/SL for local signal conditioning before transmitting scaled readings over UART. The 10-bit ADC samples up to 8 analog channels (thermocouple, RTD bridge, pressure transducer, flow meter) with hardware accumulation available for noise averaging. The internal 31 kHz LF oscillator plus nanoWatt sleep enables cycle-sleep architectures where the MCU wakes on a timer interrupt, samples, transmits, and returns to sub-microamp sleep. The 256B EEPROM stores calibration coefficients and sensor serial numbers across power cycles.
Recommended
Lighting Control (LED Driver MCU)
The PIC16F688-I/SL drives LED lighting controllers where it generates PWM dimming signals via its ECCP module, reads ambient-light sensors via the 10-bit ADC, and communicates with upstream home-automation buses via USART. Its 7KB flash accommodates firmware for CCT (correlated color temperature) blending, flicker-free dim curves, and DALI/Casambi protocol stacks. The 14-SOIC footprint fits inside MR16 bulbs and linear LED tubes where board space is constrained.
Recommended
Small Industrial Automation Modules
Compact industrial modules - pump controllers, valve drivers, conveyor segment controllers - use the PIC16F688-I/SL because its 2.0-5.5V supply range tolerates 24V industrial rails with simple linear regulation, and its 12 I/O pins are sufficient for end-stop sensors, motor-direction H-bridges, and indicator LEDs. The 200 ns deterministic instruction cycle enables precise time-based control loops, while the on-chip analog comparator implements window comparators for sensor-level detection. RS-485 connectivity is added through an external transceiver talking to the on-chip USART.
Recommended
Remote Control / IR Transmitter
Consumer remote controls and IR/RF transmitters use the PIC16F688-I/SL because its 7KB flash is more than enough for protocol stacks (RC5, NEC, Sony SIRC, ZigBee RF4CE) and its nanoWatt sleep draws sub-microamp current from coin cells, achieving multi-year battery life. The ECCP module generates the 38 kHz carrier modulation for IR LEDs, while the 10-bit ADC reads battery voltage for low-battery indicators. The 14-SOIC footprint allows single-side PCB layouts that fit inside slim remote housings.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F688-I/SL β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F688-E/SL |
|---|---|---|
| Brand | Microchip Technology | Microchip Technology - same |
| Package | 14-SOIC (SL) | 14-SOIC (SL) - same |
| Program Memory (Flash) | 7 KB | 7 KB |
| Data SRAM | 256 B | 256 B |
| Data EEPROM | 256 B | 256 B |
| Maximum Clock Frequency | 20 MHz | 20 MHz |
| Operating Voltage Range | 2.0 V to 5.5 V | 2.0 V to 5.5 V |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +125C (Extended) |
| I/O Pins | 12 | 12 |
| Lifecycle Status | Active | Active |
Key Differentiators
- On-chip 256-byte EEPROM included (vs PIC16F628A)
- Larger flash and RAM than 8-bit 8-pin siblings (vs PIC16F630-I/SL)
- Internal 8 MHz oscillator calibrated across VDD range (vs Discrete 8 MHz crystal + load capacitors)
Design Notes
The PIC16F688-I/SL accepts 2.0-5.5V on VDD. For designs running from a 24V industrial rail, use an MC78L05 (TO-92) or MCP1700 (SOT-23) LDO with a 100 nF input bypass and 10 uF output bulk; the MCU draws under 11 mA active at 20 MHz, leaving regulator headroom. Place a 100 nF ceramic decoupling cap within 5 mm of the VDD pin; add a 10 uF tantalum or ceramic bulk cap at the regulator output for nanoWatt sleep stability.
Pin RA3/MCLR/VPP is a shared MCLR reset and ICSP programming voltage pin. If left as a floating digital input, it can randomly reset the MCU. Always tie RA3 to VDD through a 10 kohm pull-up resistor. When using ICSP, ensure the ICSPDAT/ICSPCLK lines (RA0/RA1) do not have series resistors or capacitors - they must connect directly to the programming header for reliable flash programming.
Configure unused I/O pins as outputs driving low (not inputs floating) to minimize sleep current. For ADC inputs, ensure source impedance is below 10 kohm to avoid ADC acquisition-time errors; if higher-impedance sensors are used (e.g. a resistor divider > 50 kohm), add an op-amp buffer. When using the internal 8 MHz HFINTOSC, calibrate with the OSCTUNE register if UART baud-rate accuracy must be within 2%.
Compliance Information
RoHS-compliant per Microchip product page. Not AEC-Q100 qualified; automotive designs should consider PIC16F18325 or AEC-Q100-graded PIC16 alternatives.
