PIC16F15256-I/STX - 8-Bit MCU, 28KB Flash, 32MHz, 28-VQFN | Microchip
MPN: PIC16F15256-I/STX β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.62 | $1.62 |
| 10 | $1.46 | $14.60 |
| 100 | $1.21 | $121.00 |
| 500 | $1.04 | $520.00 |
| 1,000 | $0.93 | $930.00 |
| 3,000 | $0.85 | $2,550.00 |
PIC16F15256-I/STX Overview
An 8-bit microcontroller (MCU) is a small computer-on-a-chip that combines a CPU, non-volatile program memory, volatile data memory, and a curated set of digital and analog peripherals around a Harvard or modified-Harvard bus. Within the broader taxonomy, the PIC16F15256 belongs to the 8-bit MCU class -> PIC microcontrollers -> PIC16 family -> PIC16F152xx sub-family, and ultimately to the embedded processing semiconductor category that also includes 16-bit dsPIC, 32-bit ARM Cortex-M, and RISC-V microcontrollers. Its role in any system is to read sensors, run deterministic control loops, and drive actuators, displays, or communication busses.
Key features include up to 32MHz internal oscillator operation, 28KB self-programmable Flash with code protection, 2KB SRAM, an 18-channel 10-bit ADC, two 10-bit PWM outputs with two CCP modules, an EUSART (RS-232/RS-485), SPI and I2C with address masking, a hardware limit timer (HLT), windowed watchdog timer, and Microchip's eXtreme Low-Power (XLP) sleep modes drawing under 50 nA typical. The Peripheral Pin Select block remaps most digital peripherals to a wide choice of I/O pins, easing PCB layout.
Architecturally, the PIC16F15256 uses Microchip's enhanced mid-range 8-bit core with a hardware multiplier, single-cycle instruction fetch, and 256-byte EEPROM data memory. The on-chip voltage regulator supports operation from 1.8V to 5.5V across -40C to +85C industrial range. Built-in Core Independent Peripherals such as the CWG, NCO, and HLT allow complex waveform, frequency, and timing functions to execute without CPU intervention, freeing the core for application logic.
Typical applications include IoT sensor end nodes, battery-powered HVAC and thermostat controls, white-goods and small appliance controllers, low-cost BLDC fan and pump drivers, lighting controllers, and remote-control user-interface boards. The combination of small 4x4 mm VQFN footprint and rich analog/digital mix suits compact, cost-constrained designs.
Design consideration: when migrating from a 28-pin SPDIP/SOIC PIC16, the VQFN-28 (4x4) STX package requires a 0.4 mm pitch land pattern with an exposed thermal pad that MUST be soldered to the ground plane for thermal and electrical performance; skip this and the part may overheat or exhibit reset issues at full peripheral load.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC16F15256-I/STX β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
PIC16F15274-I/STX
β Drop-Inπ Reference alternative (not in catalog)
PIC16F15276-I/STX
β Drop-Inπ Reference alternative (not in catalog)
PIC16F15256-I/STX Maximum Ratings & Electrical Characteristics
| Device Family | PIC16F152xx |
| Core Architecture | 8-bit PIC enhanced mid-range |
| Program Memory (Flash) | 28 KB (28K x 8) |
| Data SRAM | 2 KB |
| EEPROM | 256 B |
| Maximum CPU Speed | 32 MHz |
| Operating Voltage Range | 1.8 V to 5.5 V |
| ADC | 10-bit, up to 18 channels |
| PWM Channels | 2 x 10-bit |
| CCP Modules | 2 |
| Communication Peripherals | 1 x EUSART, 1 x SPI, 1 x I2C |
| Peripheral Pin Select (PPS) | Yes |
| Hardware Limit Timer (HLT) | Yes |
| Watchdog Timer | Windowed WDT |
| eXtreme Low-Power (XLP) Sleep | Yes (<50 nA typical) |
| Operating Temperature Range | -40C to +85C (Industrial, 'I') |
| Package | 28-pin VQFN (4x4 mm) with exposed pad |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC16F15256-I/STX Pin Configuration
| Pin 1 | RA2 β Port A bit 2 / analog input / digital I/O with PPS |
| Pin 2 | RA3 β Port A bit 3 / analog input / digital I/O |
| Pin 3 | RA4 β Port A bit 4 / analog input / digital I/O |
| Pin 4 | RA5 β Port A bit 5 / analog input / digital I/O |
| Pin 5 | VDD β Positive supply voltage (1.8V to 5.5V) |
| Pin 6 | VSS β Ground reference |
| Pin 7 | RA6 β Port A bit 6 / digital I/O |
| Pin 8 | RA7 β Port A bit 7 / digital I/O / ICSPCLK |
| Pin 9 | RA1 β Port A bit 1 / analog input / digital I/O |
| Pin 10 | RA0 β Port A bit 0 / analog input / ICSPDAT |
| Pin 11 | RA3 β Port A bit 3 (alternate position) |
| Pin 12 | RC0 β Port C bit 0 / analog input / digital I/O |
| Pin 13 | RC1 β Port C bit 1 / analog input / digital I/O |
| Pin 14 | RC2 β Port C bit 2 / analog input / digital I/O |
| Pin 15 | RC3 β Port C bit 3 / analog input / digital I/O |
| Pin 16 | RC4 β Port C bit 4 / digital I/O |
| Pin 17 | RC5 β Port C bit 5 / digital I/O |
| Pin 18 | RC6 β Port C bit 6 / digital I/O |
| Pin 19 | RC7 β Port C bit 7 / digital I/O |
| Pin 20 | RB0 β Port B bit 0 / analog input / digital I/O |
| Pin 21 | RB1 β Port B bit 1 / analog input / digital I/O |
| Pin 22 | RB2 β Port B bit 2 / analog input / digital I/O |
| Pin 23 | RB3 β Port B bit 3 / analog input / digital I/O |
| Pin 24 | RB4 β Port B bit 4 / analog input / digital I/O |
| Pin 25 | RB5 β Port B bit 5 / analog input / digital I/O |
| Pin 26 | RB6 β Port B bit 6 / ICSPCLK / digital I/O |
| Pin 27 | RB7 β Port B bit 7 / ICSPDAT / digital I/O |
| Pin 28 | EP β Exposed thermal pad - must be soldered to ground plane |
Typical Applications
PIC16F15256-I/STX is suitable for 7 applications: IoT Sensor End Nodes, Battery-Powered HVAC and Thermostat Controls, Small Appliance and White-Goods Controllers, Low-Cost BLDC Fan and Pump Drivers, LED Lighting Controllers, Remote Control and User Interface Boards, Industrial Sensor and Process Modules.
IoT Sensor End Nodes
The PIC16F15256-I/STX suits battery-powered IoT sensor end nodes thanks to its XLP sleep current under 50 nA typical, 1.8V-5.5V Vdd range, 32MHz/8 MIPS core, and 10-bit ADC with up to 18 channels. The 18-channel ADC enables multi-sensor reading (temperature, humidity, light, voltage) without an external mux; the 28KB Flash accommodates MQTT-SN or LoRaWAN stack fragments plus sensor calibration tables. PPS remaps serial peripherals to free pins, and the 4x4 mm VQFN footprint fits inside small sensor puck enclosures.
Recommended
Battery-Powered HVAC and Thermostat Controls
Thermostat and HVAC control boards benefit from the PIC16F15256-I/STX's combination of 10-bit ADC for temperature sensing (NTC thermistor or digital sensor input), 2x PWM outputs for damper or valve actuation, and EUSART for communication with the HVAC master controller. XLP sleep currents under 50 nA let battery-only thermostats achieve multi-year life on 2x AA cells. The 2KB SRAM supports smooth UI state machines, and 28KB Flash holds HVAC state diagrams plus optional BLE provisioning routines.
Recommended
Small Appliance and White-Goods Controllers
For coffee makers, blenders, washing machine control boards, and similar white-goods, the PIC16F15256-I/STX provides the right mix of 2 PWM channels, 2 CCP, hardware limit timer (HLT) for safety cutoffs, and EUSART for HMI panel communication. The -40C to +85C industrial temperature range supports under-counter or garage installations. 28KB Flash fits full UI state machines plus fault logging, and the exposed pad on the VQFN enables reliable thermal dissipation inside enclosed appliance chassis.
Recommended
Low-Cost BLDC Fan and Pump Drivers
The PIC16F15256-I/STX's CWG (Complementary Waveform Generator), NCO (Numerically Controlled Oscillator), and 2 PWM channels make it suitable for low-power BLDC fan or peristaltic pump control with back-EMF sensing via the 10-bit ADC. The hardware limit timer adds a hardware-level safety cutoff independent of firmware execution, an important safety feature for unattended pump installations. PPS allows placing PWM outputs on pins optimized for the gate-driver PCB layout.
Recommended
LED Lighting Controllers
Smart LED drivers and architectural lighting controllers benefit from the PIC16F15256-I/STX's PWM channels for dimming, I2C address masking for RGBW fixture addressing, and 28KB Flash for DMX/RDM or DALI command parsing. The 32MHz core handles 8-bit PWM resolution at high frequency to avoid flicker in film/video contexts. SPI can drive high-density LED matrices via shift registers, and the small VQFN footprint fits inside compact GU10 or MR16 form-factor LED modules.
Recommended
Remote Control and User Interface Boards
Universal remote controls, smart-home keypads, and HMI panels use the PIC16F15256-I/STX as their controller: 10-bit ADC reads resistive touch or joystick inputs, PWM drives vibration motors, EUSART or SPI connects to a wireless companion chip (BLE/Zigbee/LoRa), and 28KB Flash stores key maps plus IR code libraries. The 2KB SRAM supports multi-layer menu navigation without thrashing, and PPS allows reassigning pins during PCB revisions without code rework.
Recommended
Industrial Sensor and Process Modules
Industrial 4-20 mA loop-powered sensor modules, panel meters, and small process controllers use the PIC16F15256-I/STX for ADC-based sensor readout, UART for Modbus RTU communication, and EEPROM-backed calibration storage. The 1.8V-5.5V wide supply range supports operation from 24V industrial rails via simple LDO down-conversion. XLP sleep extends battery life in wireless HART field instruments, and the -40C to +85C rating covers outdoor and cabinet-mounted installations.
Recommended
Recommended Products Summary
Engineering reference data for PIC16F15256-I/STX β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC16F15274-I/STX | PIC16F15276-I/STX |
|---|---|---|---|
| Package | 28-VQFN (4x4) | 28-VQFN (4x4) - same | 28-VQFN (4x4) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Program Memory | 28 KB | 56 KB (+100%) | 56 KB (+100%) |
| SRAM | 2 KB | 4 KB (+100%) | 4 KB (+100%) |
| CPU Speed | 32 MHz / 8 MIPS | 32 MHz / 8 MIPS | 32 MHz / 8 MIPS |
| Operating Voltage | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| 10-bit ADC Channels | Up to 18 | Up to 18 | Up to 18 |
| PWM Channels | 2 x 10-bit | 2 x 10-bit | 2 x 10-bit |
| PPS (Peripheral Pin Select) | Yes | Yes | Yes |
| XLP Sleep Current | <50 nA typical | <50 nA typical | <50 nA typical |
Key Differentiators
- Higher Flash/RAM density in the same VQFN footprint (vs PIC16F15274-I/STX)
- Industrial temperature range with same peripherals as commercial-grade cousins (vs PIC16F15254-I/SS)
- Compact 4x4 mm VQFN with rich peripheral set (vs PIC16F15255-I/SP)
Design Notes
The 28-VQFN (4x4) STX package uses a center exposed thermal pad that MUST be soldered to a grounded copper pour to meet thermal and electrical specifications. Minimum recommended copper area is 1 square inch of 1 oz copper on at least one PCB layer. Without this, the die may overheat at elevated peripheral activity, leading to thermal-reset behavior or oscillator drift.
For the 0.4 mm pitch VQFN-28 land pattern, use NSMD (non-solder mask defined) pads with a stencil aperture ratio that delivers approximately 0.1 mm paste thickness; this minimizes mid-pad solder voids under the thermal pad and avoids the 'floating pad' issue that triggers thermal issues. Place a 0.1uF X7R bypass capacitor within 2 mm of VDD pin 5, with a 1uF bulk cap close by.
When migrating code from a PIC16F15255-I/SP (28-SPDIP) prototype to the PIC16F15256-I/STX (28-VQFN), verify PPS remapping: the VQFN package shares the same RA/RB/RC port layout as the SPDIP, but if your firmware uses absolute pin numbers for SPI/UART, you may need to reconfigure the PPS registers. Always burn the BOR (Brown-Out Reset) and PWRT (Power-up Timer) configuration bits to avoid erratic startup at low Vdd.
Compliance Information
RoHS and REACH compliant per Microchip product environmental compliance information. Lead-free matte-tin finish. Not AEC-Q100 qualified - for automotive applications use the PIC16F15256-E/STX automotive grade variant or a Q100-qualified PIC16F equivalent.
