Let's Make Robots!

COSMA's brain

Attached you find the Rev. 0 schematic of COSMA's brain (Eagle). This board connects directly to a FTDI  board. As I need MOSI, MISO and SCK also for the micro SD card, I added solder jumpers, so those pins are not connected to the SD card/voltage level shifter while burning the bootloader on the chip.

The board mainly contains:

- ATMEGA2560

- Micro SD card socket

- Voltage level shifter HEF4050 for the SD card

- MPU 6050 (6 DOF accelerometer/gyroscope)

- I2C voltage level shifter for the MPU 6050 based on BSS138 N-channel MOSFETs

- DS1307 based RTC with backup Lithium coin cell battery

- Connectors for DS18B20 temperture sensor, 8 FSRs, 2 analog sound sensors, ArduEye and EMIC-2

- 1.5A LDO (LM1086) for servos

- 1.5A LDO (LM1086) for 5V devices

- 400mA LDO (MIC2920) for 3.3V devices

Let me know if you have any suggestions, improvement ideas or seeing any design flaws :)

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Cosmo_motherboard_schematic.pdf97.58 KB