Specifications Feature Teensy 4.1 Teensy 4.0 Ethernet 10 / 100 Mbit DP83825 PHY (6 pins) -none- USB Host 5 Pins with power management 2 SMT Pads SDIO (4 bit data) Micro SD Socket 8 SMT Pads PWM Pins 35 31 Analog Inputs 18 14 Serial Ports 8 7 Flash Memory 8 Mbyte 2 Mbyte QSPI Memory 2 chips + Program Memory Program memory Breadboard I/O 42 24 Bottom SMT Pads 7 16 SD Card Signals 6 0 Total I/O Pins 55 40 Differences between Teensy 4.1 & Teensy 4.0 ARM Cortex-M7 at 600 MHz Float point math unit, 64 & 32 bits 1984K Flash, 1024K RAM (512K tightly coupled), 1K EEPROM (emulated) USB device 480 Mbit/sec & USB host 480 Mbit/sec 40 digital input/output pins, 31 PWM output pins 14 analog input pins 7 serial, 3 SPI, 3 I2C ports 2 I2S/TDM and 1 S/PDIF digital audio port 3 CAN Bus (1 with CAN FD) 32 general purpose DMA channels Cryptographic Acceleration & Random Number Generator RTC for date/time Programmable FlexIO Pixel Processing Pipeline Peripheral cross triggering Power On/Off management