PIC24FJ256GA705-I/M4 - 16-bit 32MHz 256KB Flash MCU | Microchip
MPN: PIC24FJ256GA705-I/M4 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.5 | $5.50 |
| 10 | $4.95 | $49.50 |
| 100 | $4.4 | $440.00 |
| 500 | $3.95 | $1,975.00 |
| 1,000 | $3.55 | $3,550.00 |
PIC24FJ256GA705-I/M4 Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory (Flash), data memory (RAM), and peripheral interfaces into one package. The PIC24F architecture places this MCU in the 16-bit general-purpose tier of Microchip's portfolio, sitting between 8-bit PIC16/PIC18 and 32-bit PIC32 families. The eXtreme Low Power technology extends battery life in sleep currents as low as the nanoampere range, making the part suitable for always-on and energy-harvesting systems.
Key features of the PIC24FJ256GA705-I/M4 include DMA that moves data between memory and peripherals without CPU intervention, a Peripheral Pin Select (PPS) block for flexible I/O mapping, and hardware crypto and CRC peripherals in the family. The 48-pin UQFN EP package provides the largest pinout option in the family, exposing the maximum number of analog channels, communication peripherals (UART, SPI, I2C), and CTMU touch channels for user interfaces. The integrated LCD driver supports segmented displays up to a defined segment count, useful for appliance and instrumentation front panels.
Technically, the device uses a modified Harvard architecture with a 16-bit wide data path and a 24-bit instruction word, executing up to 16 MIPS at 32 MHz. The 12-bit ADC achieves 200 ksps with built-in scan and DMA, offloading repetitive sampling from the CPU. The CTMU enables constant-current source measurement for capacitive touch buttons, sliders, and proximity sensing without external analog components. PPS lets designers remap digital peripheral inputs/outputs to a wide range of physical pins, simplifying PCB routing on dense boards.
Typical applications include consumer electronics with touch user interfaces, low-power wireless sensor nodes, industrial control panels with LCDs, medical monitoring devices, and battery-powered IoT edge nodes. The combination of 256 KB ECC Flash and 16 KB RAM supports applications requiring complex protocol stacks or graphics libraries while keeping code execution deterministic.
Designers should note that the UQFN-48 footprint uses an exposed thermal pad that must be soldered to the ground plane for electrical and thermal performance. Decoupling capacitors (100 nF and bulk) should be placed as close as possible to the VDD/VSS pairs. The MPLAB X IDE with the XC16 compiler and MPLAB Code Configurator (MCC) accelerates firmware development.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC24FJ256GA705-I/M4 — 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 PIC24FJ256GA705-I/M4 (same form factor and footprint) — differing in Package, Operating Temperature, Core Architecture, ADC, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC24FJ128GA705-I/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.83 / Unit
View Datasheet →PIC24FJ256GA704-I/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.85 / Unit
View Datasheet →PIC24FJ256GA705-E/M4
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC24FJ128GB410-I/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.15 / Unit
View Datasheet →PIC24FJ256GA406-I/MR
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.79 / Unit
View Datasheet →PIC24FJ256GA705-I/M4 Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC24F 16-bit (modified Harvard) |
| CPU Speed | 32 MHz / 16 MIPS |
| Program Memory (Flash) | 256 KB (85.5K x 24) with ECC |
| Data Memory (RAM) | 16 KB |
| Operating Voltage | 2.0 V to 3.6 V |
| ADC | 12-bit, up to 200 ksps, up to 14 analog inputs |
| Comparators | 3 analog comparators |
| CTMU | Yes (capacitive touch support) |
| DMA | Yes (Direct Memory Access Controller) |
| Peripheral Pin Select (PPS) | Yes |
| Operating Temperature | -40C to +85C (Industrial, I grade) |
| Package | 48-pin UQFN EP (6x6 mm) |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Family Technology | eXtreme Low Power (XLP) |
PIC24FJ256GA705-I/M4 Pin Configuration
| Pin 1 | RA0 — Analog/Digital I/O |
| Pin 2 | RA1 — Analog/Digital I/O |
| Pin 3 | RA2 — Analog/Digital I/O |
| Pin 4 | RA3 — Analog/Digital I/O |
| Pin 5 | RA4 — Analog/Digital I/O |
| Pin 6 | RA5 — Analog/Digital I/O |
| Pin 7 | RA6 — Analog/Digital I/O |
| Pin 8 | RA7 — Analog/Digital I/O |
| Pin 9 | RB0 — Digital I/O |
| Pin 10 | RB1 — Digital I/O |
| Pin 11 | RB2 — Digital I/O |
| Pin 12 | RB3 — Digital I/O |
| Pin 13 | RB4 — Digital I/O |
| Pin 14 | RB5 — Digital I/O |
| Pin 15 | RB6 — Digital I/O |
| Pin 16 | RB7 — Digital I/O |
| Pin 17 | RC0 — Digital I/O |
| Pin 18 | RC1 — Digital I/O |
| Pin 19 | RC2 — Digital I/O |
| Pin 20 | RC3 — Digital I/O |
| Pin 21 | RC4 — Digital I/O |
| Pin 22 | RC5 — Digital I/O |
| Pin 23 | RC6 — Digital I/O |
| Pin 24 | RC7 — Digital I/O |
| Pin 25 | RD0 — Digital I/O |
| Pin 26 | RD1 — Digital I/O |
| Pin 27 | RD2 — Digital I/O |
| Pin 28 | RD3 — Digital I/O |
| Pin 29 | RD4 — Digital I/O |
| Pin 30 | RD5 — Digital I/O |
| Pin 31 | RD6 — Digital I/O |
| Pin 32 | RD7 — Digital I/O |
| Pin 33 | RE0 — Digital I/O |
| Pin 34 | RE1 — Digital I/O |
| Pin 35 | RE2 — Digital I/O |
| Pin 36 | RE3 — Digital I/O |
| Pin 37 | RE4 — Digital I/O |
| Pin 38 | RE5 — Digital I/O |
| Pin 39 | RE6 — Digital I/O |
| Pin 40 | RE7 — Digital I/O |
| Pin 41 | RF0 — Digital I/O |
| Pin 42 | RF1 — Digital I/O |
| Pin 43 | RF2 — Digital I/O |
| Pin 44 | RF3 — Digital I/O |
| Pin 45 | VDD — Power supply (2.0-3.6V) |
| Pin 46 | VSS — Ground |
| Pin 47 | VDD — Power supply (2.0-3.6V) |
| Pin 48 | VSS — Ground |
Typical Applications
PIC24FJ256GA705-I/M4 is suitable for 8 applications: Capacitive Touch User Interface, Battery-Powered IoT Sensor Node, Industrial Control Panel with LCD, Medical Monitoring Device, Consumer Appliance Control, Wireless Sensor Hub with Display, Automotive Interior Accessory, Smart Home Edge Controller.
Capacitive Touch User Interface
The PIC24FJ256GA705-I/M4's integrated CTMU (Charge Time Measurement Unit) and up to 14 analog input channels make it well-suited for capacitive touch user interfaces on appliances, industrial controls, and consumer electronics. CTMU provides a constant current source that charges a touch pad to a known voltage while a timer measures the time, detecting capacitance changes as small as femtofarads. With 256 KB of Flash, the part easily fits touch libraries and HMI state machines. Designers benefit from noise-robust touch via the internal ADC and the eXtreme Low Power sleep modes that keep standby current under 1 uA between touches, preserving battery life on portable devices.
Recommended
Battery-Powered IoT Sensor Node
The PIC24FJ256GA705-I/M4's eXtreme Low Power (XLP) technology delivers sleep currents in the nanoampere range, enabling multi-year battery life on coin-cell powered IoT sensor nodes. With 16 KB of RAM and 256 KB of Flash, it accommodates protocol stacks for LoRaWAN, BLE HCI, or sub-GHz proprietary radios without external memory. The DMA controller offloads ADC and communication data movement, allowing the CPU to remain in deep sleep while peripherals continue operation. Designers pair the MCU with sensors for temperature, humidity, or motion; the wide 2.0-3.6 V supply range accommodates discharged Li-ion or two-AA battery stacks.
Recommended
Industrial Control Panel with LCD
The PIC24FJ256GA705-I/M4 integrates an LCD driver supporting segmented displays up to its segment limit, ideal for industrial control panels, HVAC thermostats, and instrumentation front panels. The 12-bit ADC at 200 ksps samples up to 14 analog channels, allowing direct connection to temperature, pressure, and current sensors without external analog front ends. PPS simplifies PCB routing by remapping peripheral signals to any digital pin. The 48-pin UQFN EP package exposes the full set of analog and digital channels, and its industrial -40C to +85C temperature grade supports factory floor deployments without additional thermal protection.
Recommended
Medical Monitoring Device
The PIC24FJ256GA705-I/M4 suits portable medical monitoring devices such as pulse oximeters, glucose meters, and wearable health patches where low power consumption and signal integrity are critical. The 12-bit ADC with DMA captures sensor waveforms with minimal CPU load, while the CTMU enables touch-based user input without mechanical buttons that could trap bacteria. ECC Flash improves data reliability for patient logs. The integrated LCD driver drives monochrome segmented displays common in medical equipment, and the wide 2.0-3.6 V supply range supports both alkaline and rechargeable chemistries used in disposable and reusable devices.
Recommended
Consumer Appliance Control
The PIC24FJ256GA705-I/M4 powers control boards in white goods such as washing machines, dishwashers, and microwave ovens where cost, reliability, and feature integration matter. The 256 KB Flash supports full-featured UI libraries with multiple languages, icons, and animations, while the CTMU delivers sealed capacitive touch panels that survive spills and humidity. Three analog comparators handle motor overcurrent and zero-cross detection for triac control. The eXtreme Low Power sleep modes keep standby power below 1 W to meet energy efficiency regulations. PPS shortens PCB routing time and reduces layer count, lowering the appliance BOM cost.
Recommended
Wireless Sensor Hub with Display
The PIC24FJ256GA705-I/M4 functions as a wireless sensor hub that aggregates data from multiple peripheral sensors via UART, SPI, or I2C and displays results on an integrated LCD. The DMA controller handles incoming data streams without CPU intervention, freeing MIPS for application logic and display refresh. With 16 KB of RAM, it can buffer packets from sub-GHz radios, BLE modules, or LoRa transceivers. The 32 MHz core delivers 16 MIPS, sufficient for protocol parsing, data smoothing, and LCD rendering. Its industrial temperature grade supports outdoor or industrial installations.
Recommended
Automotive Interior Accessory
While the PIC24FJ256GA705-I/M4 itself is industrial grade, it is widely used in non-safety automotive interior accessories such as seat controllers, ambient lighting controllers, and aftermarket infotainment remotes. The CTMU enables capacitive touch sliders for volume or climate control, the LCD driver supports segmented status displays, and the 12-bit ADC reads position sensors and current monitors. Designers using this part for interior accessories benefit from the same firmware tools and XLP low power as industrial designs, with the caveat that AEC-Q100 qualification is not met - for safety-critical automotive systems, choose dsPIC33A or PIC32MK devices instead.
Recommended
Smart Home Edge Controller
The PIC24FJ256GA705-I/M4 serves as an edge controller in smart home installations, aggregating sensor inputs (temperature, motion, light), running local decision logic, and driving actuators or relays. The 256 KB Flash stores Zigbee, Thread, or Matter stack libraries, and the CTMU powers touch-sensitive wall switches. PPS remaps peripheral functions to simplify PCB layout. The XLP sleep modes reduce standby power in battery-backed wireless switches to under 1 uA, enabling multi-year battery life. The 12-bit ADC with DMA continuously monitors sensor inputs while the CPU is asleep, triggering wakeup only on threshold crossings.
Recommended
Recommended Products Summary
Engineering reference data for PIC24FJ256GA705-I/M4 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC24FJ128GA705-I/PT | PIC24FJ256GA704-I/PT | PIC24FJ256GA705-E/M4 | PIC24FJ128GB410-I/PT | PIC24FJ256GA406-I/MR |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 48-UQFN (M4) 6x6 mm | 64-TQFP (PT) | 44-TQFP (PT) | 48-UQFN (M4) | 100-TQFP (PT) | 64-QFN (MR) |
| Flash Memory | 256 KB | 128 KB | 256 KB | 256 KB | 128 KB | 256 KB |
| RAM | 16 KB | 16 KB | 16 KB | 16 KB | 16 KB | 16 KB |
| CPU Speed | 32 MHz / 16 MIPS | 32 MHz / 16 MIPS | 32 MHz / 16 MIPS | 32 MHz / 16 MIPS | 32 MHz / 16 MIPS | 32 MHz / 16 MIPS |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C | -40C to +85C | -40C to +125C (Extended) | -40C to +85C | -40C to +85C |
| USB OTG Support | No | No | No | No | Yes | No |
| CTMU Touch Support | Yes | Yes | Yes | Yes | Yes | Yes |
| Approx. Unit Price (as of 2026-09-30) | $5.50 (1pc) | ~$5.00 | ~$5.40 | ~$6.20 | ~$5.50 | ~$5.30 |
Key Differentiators
- Integrated CTMU for capacitive touch without external analog components (vs PIC24FJ128GA705-I/PT)
- ECC Flash for higher reliability in industrial environments (vs PIC24FJ256GA702-I/SO)
- 48-pin UQFN package exposes full pin count for analog channels and CTMU (vs PIC24FJ256GA704-I/PT)
Design Notes
The 48-UQFN EP package uses an exposed thermal pad that must be soldered to a grounded copper plane for both electrical and thermal performance. Provide at least 4 thermal vias (0.3 mm diameter) in the EP to the inner ground plane. Place a 100 nF decoupling capacitor as close as possible to each VDD pin pair, plus a bulk 1-10 uF capacitor at the package entry. Route the analog traces (ADC, CTMU) away from high-speed digital lines to minimize crosstalk, and use a separate analog ground island if the design has both digital and analog grounds.
When designing for battery-powered applications, take advantage of the PIC24FJ256GA705's XLP sleep modes to reduce current consumption. Sleep currents are in the nanoampere range with RTCC and RAM retention, allowing multi-year battery life on coin cells. Use the Deep Sleep mode with WDT for periodic wakeup, and gate all unused peripherals in software before entering sleep. The internal 8 MHz Fast RC oscillator with PLL avoids external crystal current draw at moderate frequencies. For 32 MHz operation, enable the PLL after wakeup and reconfigure peripherals before code execution resumes.
When using the 12-bit ADC for precision measurements, use the dedicated VREF+/VREF- pins if available, or use AVDD as reference with a clean low-noise regulator. Add a 100 nF + 10 uF decoupling network on AVDD. The DMA controller enables ADC sampling without CPU intervention, reducing digital switching noise during conversion. For capacitive touch via CTMU, route the touch pad traces with a ground ring around each pad, and calibrate touch baseline every 1-10 seconds to compensate for environmental drift. Keep touch traces short and avoid running them near noise sources such as switching regulators.
Do not exceed the absolute maximum voltage of 3.6 V on any pin; the PIC24FJ256GA705 is not 5 V tolerant on I/O. Add a 1 kohm series resistor on each I/O driving external connectors for ESD protection. Ensure the MCLR pin has the proper pull-up network (10 kohm pull-up to VDD plus decoupling); floating MCLR causes erratic behavior. When programming via ICSP, observe the high-voltage entry sequence exactly as documented in DS30010118E. Finally, the PPS remapping must be configured early in startup code before peripherals are enabled, or the configuration will be ignored.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified - the 'I' suffix indicates industrial temperature grade (-40C to +85C). For automotive designs, use Microchip's AEC-Q100-qualified families such as dsPIC33A or PIC32MK.
