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Feature-Rich Teensy 3.x Board with 5V-Tolerant Digital Inputs
The Teensy 3.5 without headers is a strong step up from smaller Teensy boards when you need more I/O, more memory, and a faster processor but still want a compact board for real embedded work.
It uses a 120 MHz ARM Cortex-M4, brings out a large number of pins, and stands out in the Teensy 3.x family because its digital input pins are 5V tolerant.
Important: This version comes without headers, which is useful for custom soldering, lower profile builds, or direct integration into your own board layout.
Why you'll love it
- More speed and memory: A stronger option than Teensy 3.2 for bigger firmware
- 5V-tolerant digital inputs: Helpful when interfacing with older 5V logic devices
- Large I/O count: Good for wide control and sensor projects
- Native SD support: Useful for logging, playback, and data storage
- Good balance of cost and capability: A practical middle ground in the legacy Teensy range
Comparison table
| Product | Best for | Core / Speed | Main edge |
|---|---|---|---|
| Teensy 3.2 | Balanced embedded, MIDI, display, sensor builds | 32-bit Cortex-M4 / 72 MHz | Well-balanced speed, 5V-tolerant digital inputs |
| Teensy 3.5 without headers | More I/O with easier 5V digital interfacing | 32-bit Cortex-M4 / 120 MHz | More I/O and 5V-tolerant digital inputs |
| Teensy 3.6 without headers | Bigger legacy builds, audio, USB host | 32-bit Cortex-M4 / 180 MHz | Legacy high-end 3.x board with USB host |
| Teensy 4.1 Development Board | Large systems, Ethernet, SD, memory expansion | 32-bit Cortex-M7 / 600 MHz | Most I/O, SD, Ethernet, memory expansion |
What you can build
Use it for robotics, machine control, data logging, embedded UI projects, synth controllers, and systems where 5V-tolerant digital inputs make integration easier.
Starter bundles
Great pairings include the Audio Adapter Board for Teensy 3.x, displays, SD storage, and header strips or sockets that match your preferred build style.
Recommended add-ons
Recommended add-ons include CAN hardware, displays, button and encoder interfaces, audio hardware, and storage parts for larger embedded builds.
Technical specifications
| Product | Teensy 3.5 without headers |
|---|---|
| Main MCU | ARM Cortex-M4 |
| Clock Speed | 120 MHz |
| Memory | 512 KB Flash, 256 KB RAM, 4 KB EEPROM |
| USB | USB device 12 Mbit/sec |
| I/O Pins | 64 digital I/O, 20 PWM |
| Analog | 27 analog inputs, 2 analog outputs |
| Communication | 6 Serial, 3 SPI, 3 I2C, 1 CAN |
| Storage | Native SDIO SD card support |
| Logic Notes | Digital pins accept 0 to 5V signals |
Pinout & power notes
Teensy 3.5 runs as a 3.3V board, but its digital input pins are 5V tolerant. That makes it easier to connect to many legacy sensors and controllers, while still giving you stronger 32-bit performance.
Official resources
Official technical specs · Pinout reference · Schematic reference · Teensyduino setup
What’s in the box
1 × Teensy 3.5 board without headers
Frequently Asked Questions
What makes Teensy 3.5 different from 3.6? Teensy 3.5 gives you 5V-tolerant digital inputs, while Teensy 3.6 focuses more on speed and higher-end features.
Is this board good for logging and storage work? Yes. Native SD support makes it useful for data logging and playback.
Does it come with headers? No. This version is sold without headers.
Can I use it with Arduino IDE? Yes. Use the Teensy boards add-on in Arduino IDE.
Manila stock. Order before 16:00 PHT, ships today via J&T or LBC. Provincial: 1–3 working days.
Schools / class POs: we accept Purchase Orders for accredited schools and universities. contact us with your PO details.
Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
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