PIC16F18856-E/STXVAO - 28KB Flash 8-bit MCU, 28-VQFN | Microchip
MPN: PIC16F18856-E/STXVAO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.18 | $3.18 |
| 10 | $2.86 | $28.60 |
| 100 | $2.55 | $255.00 |
| 500 | $2.27 | $1,135.00 |
| 1,000 | $2.04 | $2,040.00 |
PIC16F18856-E/STXVAO Overview
An 8-bit microcontroller (MCU) is a single-chip computer that combines a CPU, non-volatile program memory (typically FLASH), volatile data memory (RAM), and a configurable set of peripherals on one die. PIC microcontrollers use a Harvard RISC architecture, which separates program and data buses so the CPU can prefetch instructions while reading data, simplifying deterministic timing. Within the broader taxonomy, the PIC16F18856 belongs to: microcontroller -> 8-bit MCU -> PIC16 family -> PIC16F1885X sub-family -> power-management and CIP-rich tier of mid-range PIC devices.
Key differentiating features include the ADCC for automated analog signal averaging, the Peripheral Pin Select (PPS) for flexible signal routing, the Configurable Logic Cell (CLC) and Complementary Waveform Generator (CWG) for hardware state machines, plus brown-out reset, power-on reset, PWM, and a windowed watchdog timer. These CIPs offload work from the core, reducing code size and enabling deterministic response without CPU intervention.
The internal architecture is built on Microchip's enhanced mid-range core with a 14-bit instruction word and a hardware multiplier. With 32 MHz operation, the device delivers 8 MIPS, sufficient for sensor processing, motor control loops, and serial protocol handling in real time. The XLP features (IDLE/DOZE modes, Sleep with <50 nA typical) make the part well-suited to battery-powered or energy-harvesting applications.
Typical applications include automotive body electronics, sensor interfacing with ADCC averaging, low-power IoT endpoints, LED lighting controllers, and Functional Safety sub-systems where the FuSa documentation package aids ISO 26262 qualification. The wide 2.3V-5.5V range also accommodates direct 3.3V or 5V designs without level shifting.
When designing with this part, allocate the bottom exposed pad as a solid ground thermal relief on the PCB, follow Microchip's MSSP and PPS configuration guidelines, and respect the /VAO qualification flow if your design is automotive. Failure to bond the e-pad increases thermal resistance and can trigger long-term reliability drift.
This page consolidates current distributor pricing, verified same-family and cross-package alternatives, and design notes that extend the manufacturer datasheet with practical engineering guidance for both prototyping and production.
Drop-in alternatives for PIC16F18856-E/STXVAO — 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 PIC16F18856-E/STXVAO (same form factor and footprint) — differing in ADC, Operating Temperature, Package, Core Independent Peripherals, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC16F18856-I/STX
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F18855-I/STX
✅ Drop-In📋 Reference alternative (not in catalog)
PIC16F18855T-I/ML
✅ Drop-In✓ In Stock
$1.26 / Unit
View Datasheet →PIC16F18854-I/ML
✅ Drop-In✓ In Stock
$1.02 / Unit
View Datasheet →PIC16F18855-E/ML
✅ Drop-In✓ In Stock
$0.71 / Unit
View Datasheet →PIC16F18856-E/STXVAO Maximum Ratings & Electrical Characteristics
| Core | PIC16 8-bit RISC (enhanced mid-range, 14-bit instruction word) |
| Program Memory (FLASH) | 28 KB (16K x 14 words) |
| Data RAM | 2 KB |
| Data EEPROM | 256 B |
| Maximum CPU Speed | 32 MHz (8 MIPS) |
| Supply Voltage (Vdd) | 2.3 V to 5.5 V |
| Operating Temperature | -40 C to +125 C (E grade) |
| Package | 28-VQFN (4x4 mm) with exposed pad |
| Mounting Type | Surface Mount |
| ADC | ADC with Computation (ADCC), multiple channels |
| Timers | Multiple 8/16-bit timers with PWM |
| Communication | MSSP (I2C/SPI), EUSART, PPS |
| Core Independent Peripherals | CLC, CWG, NCO, DSM, CCP, PWM |
| Qualification | AEC-Q100, Functional Safety (FuSa) - /VAO suffix |
| Low-Power Feature | XLP with Sleep < 50 nA typical |
| Watchdog | Windowed WDT with on-chip LFO |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC16F18856-E/STXVAO Pin Configuration
| Pin 1 | RA5 — Bidirectional I/O with PPS |
| Pin 2 | RA4 — Bidirectional I/O with PPS |
| Pin 3 | RA3 — Bidirectional I/O with PPS |
| Pin 4 | RA2 — Bidirectional I/O with PPS |
| Pin 5 | RA1 — Bidirectional I/O with PPS |
| Pin 6 | RA0 — Bidirectional I/O with PPS |
| Pin 7 | VSS — Ground reference |
| Pin 8 | RA7 — Bidirectional I/O with PPS |
| Pin 9 | RA6 — Bidirectional I/O with PPS |
| Pin 10 | RC0 — Bidirectional I/O with PPS |
| Pin 11 | RC1 — Bidirectional I/O with PPS |
| Pin 12 | RC2 — Bidirectional I/O with PPS |
| Pin 13 | RC3 — Bidirectional I/O with PPS |
| Pin 14 | RC4 — Bidirectional I/O with PPS |
| Pin 15 | RC5 — Bidirectional I/O with PPS |
| Pin 16 | RC6 — Bidirectional I/O with PPS |
| Pin 17 | RC7 — Bidirectional I/O with PPS |
| Pin 18 | VSS — Ground reference |
| Pin 19 | RB7 — Bidirectional I/O with PPS |
| Pin 20 | RB6 — Bidirectional I/O with PPS |
| Pin 21 | RB5 — Bidirectional I/O with PPS |
| Pin 22 | RB4 — Bidirectional I/O with PPS |
| Pin 23 | RB3 — Bidirectional I/O with PPS |
| Pin 24 | RB2 — Bidirectional I/O with PPS |
| Pin 25 | RB1 — Bidirectional I/O with PPS |
| Pin 26 | RB0 — Bidirectional I/O with PPS |
| Pin 27 | VDD — Positive supply (2.3V-5.5V) |
| Pin 28 | VDD — Positive supply (2.3V-5.5V) |
Typical Applications
PIC16F18856-E/STXVAO is suitable for 6 applications: Automotive Body Electronics, Low-Power IoT Sensor Nodes, LED Lighting and Signage Controllers, Industrial Sensor Conditioning, Small Motor and Solenoid Control, Functional Safety Subsystems.
Automotive Body Electronics
The PIC16F18856-E/STXVAO is well suited to automotive body electronics such as lighting controllers, seat modules, mirror adjusters, and HVAC blend-door actuators where AEC-Q100 with -40 C to +125 C and Functional Safety (FuSa) documentation are required. Its 28 KB of FLASH holds typical LIN-based body controller stacks plus diagnostic routines, while 2 KB RAM is sufficient for state-machine scheduling and PWM commutation. The ADCC channel count supports multiple temperature and position sensor inputs, and the CWG peripheral can drive MOSFET half-bridges for motor control. Compared with non-automotive 8-bit MCUs, the /VAO grade gives OEMs the PPAP and FMEDA evidence needed for ISO 26262 qualification.
Recommended
Low-Power IoT Sensor Nodes
The PIC16F18856-E/STXVAO fits battery-powered IoT sensor endpoints such as wireless environmental monitors, smart thermostats, and predictive-maintenance vibration sensors thanks to its eXtreme Low Power (XLP) Sleep mode below 50 nA. Its 32 MHz core and 2 KB RAM can run small RTOS loops or cooperative taskers while leaving the ADCC to average sensor samples in hardware, freeing the CPU for protocol handling on the MSSP/EUSART. The CLC, NCO, and DSM peripherals implement wake-up logic and tone generation without software overhead. At a 2.3-5.5 V supply, the part runs directly from a single lithium cell or a 3.3 V regulated rail.
Recommended
LED Lighting and Signage Controllers
For architectural LED lighting, signage pixel drivers, and horticulture fixtures, the PIC16F18856-E/STXVAO offers enough PWM channels and CWG resources to drive multi-channel constant-current LED drivers directly. The 32 MHz core sustains DMX, DALI, or proprietary LED protocols while the ADCC channels monitor thermistors for thermal foldback. The exposed thermal pad keeps the die cool under continuous high-frequency PWM, and the wide 2.3-5.5 V range lets the design accept 5 V or 12 V buck-derived rails. Drop-in same-package parts like the PIC16F18855 family simplify SKU scaling.
Recommended
Industrial Sensor Conditioning
In industrial 4-20 mA loop transmitters, thermocouple front-ends, and bridge sensor signal conditioners, the PIC16F18856-E/STXVAO delivers an integrated ADCC for hardware-averaged readings, which is critical for stable measurements in noisy plant environments. Its 28 KB FLASH accommodates linearization tables for thermocouples and RTDs, while the MSSP/I2C peripheral links to external EEPROM or digital potentiometers. The CLC and DSM peripherals synthesize excitation waveforms for ratiometric bridge measurements. The -40 C to +125 C E grade plus AEC-Q100 /VAO qualification gives extra margin in factories with wide temperature swings.
Recommended
Small Motor and Solenoid Control
The PIC16F18856-E/STXVAO drives small DC motors, stepper windings, and solenoid valves via its PWM and Complementary Waveform Generator (CWG) peripherals, with the ADCC providing back-EMF or current sensing. Its deterministic 8 MIPS throughput is enough for closed-loop PI control at modest RPM, and the Configurable Logic Cell (CLC) implements hardware interlocks without CPU latency. The /VAO grade supports automotive accessory motors such as fuel-door locks and tailgate actuators. The 28-VQFN's exposed pad simplifies PCB thermal layout for continuous-drive applications.
Recommended
Functional Safety Subsystems
Because the /VAO suffix adds Microchip's Functional Safety documentation package (FMEDA, safety manual, diagnostic coverage data), the PIC16F18856-E/STXVAO is a good fit for ISO 26221 ASIL-rated sub-systems such as airbag squib drivers' auxiliary controllers, electronic parking brakes, and battery management BMS slaves. The windowed watchdog with on-chip LFO plus brown-out and power-on reset provide the diagnostic primitives safety integrators expect. PPS-mappable peripherals let designers isolate fault domains on the die. Pin-compatible /VAO siblings such as the PIC16F18877 series enable memory scaling while keeping the safety case intact.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F18856-E/STXVAO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F18856-I/STX | PIC16F18855-I/STX | PIC16F18855T-I/ML | PIC16F18854-I/ML | PIC16F18855-E/ML |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-VQFN (4x4) exposed pad | 28-VQFN (4x4) - same | 28-VQFN (4x4) - same | 28-VQFN (4x4) - same | 28-VQFN (4x4) - same | 28-VQFN (4x4) - same |
| FLASH Program Memory | 28 KB | 28 KB | 14 KB | 14 KB | 7 KB | 14 KB |
| Data RAM | 2 KB | 2 KB | 2 KB | 2 KB | 2 KB | 2 KB |
| Maximum CPU Speed | 32 MHz (8 MIPS) | 32 MHz | 32 MHz | 32 MHz | 32 MHz | 32 MHz |
| Operating Temperature | -40C to +125C (E grade) | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +125C |
| Automotive /VAO Grade | Yes (AEC-Q100 + FuSa) | No | No | No | No | No |
| Supply Voltage | 2.3V to 5.5V | 2.3V to 5.5V | 2.3V to 5.5V | 2.3V to 5.5V | 2.3V to 5.5V | 2.3V to 5.5V |
| Core Independent Peripherals | CLC, CWG, NCO, DSM, CCP, PWM | Same | Same | Same | Same | Same |
Key Differentiators
- Functional Safety (FuSa) documentation included (vs PIC16F18856-I/STX)
- Largest program memory in 28-VQFN PIC16F1885X family (vs PIC16F18855-I/STX)
- Extended -40 C to +125 C operating range plus AEC-Q100 (vs PIC16F18854-I/ML)
Design Notes
The 28-VQFN's exposed thermal pad must be soldered to a continuous ground copper pour with multiple thermal vias to keep junction temperature within the AEC-Q100 /VAO -40 C to +125 C envelope. Under typical 32 MHz active current of a few mA plus I/O switching, the die dissipation is modest, but missing or starved e-pad solder joints raise theta_JA and can cause long-term reliability drift. Follow Microchip's package outline drawing for the via count and pitch.
Place VDD/VSS decoupling (100 nF ceramic plus 1-10 uF bulk) within 2 mm of each supply pin pair. Use a star-ground topology tying the VQFN exposed pad, VSS pins, and decoupling capacitor grounds to one continuous plane. Route PPS-mapped peripheral signals (MSSP I2C/SPI, EUSART, PWM) away from analog ADCC inputs to minimize digital crosstalk into sensitive measurements.
Do not assume any 28-VQFN PIC16F1885X is pin-compatible with non-PIC microcontrollers; the PPS, CLC, and CIP registers are unique to Microchip's PIC architecture. When migrating across 18854/18855/18856, confirm that FLASH size still fits the firmware image, and verify that the configuration words for oscillator, watchdog, and brown-out reset match the /VAO safety case if the application is automotive. Failure to update the configuration words can lock the device out or skip required diagnostics.
Estimated: With one ground via every 1 mm under the e-pad and a 1 oz copper pour on outer layers, the effective theta_JA for a 28-VQFN (4x4) on a 4-layer PCB is approximately 30-40 C/W, versus >80 C/W without e-pad soldering. Designers targeting continuous high-current GPIO toggling should size the copper pour to keep junction rise under 50 C above ambient. Always confirm with thermal characterization on the final PCB.
Compliance Information
AEC-Q100 qualified with /VAO Functional Safety (FuSa) documentation per Microchip automotive grade scheme. RoHS and lead-free compliant per Microchip product page. Halogen-free status not stated in the provided data; flagged as unknown.
