Info:
The target voltage is set to 3.3V in production. It can be changed through MPLAB X
project properties, and in the Atmel Studio device programming dialog. Any change to the target
voltage is persistent, even through a power toggle.
The MIC5353 supports a maximum current load of 500 mA. It is an LDO regulator in a small package,
placed on a small PCB, and the thermal shutdown condition can be reached at lower loads than 500 mA.
The maximum current load depends on the input voltage, the selected output voltage, and the ambient
temperature. The figure below shows the safe operating area for the regulator, with an input voltage of
5.1V and an ambient temperature of 23
°
C.
Figure 3-3. Target Regulator Safe Operation Area
3.3.2
External Supply
ATtiny1607 Curiosity Nano can be powered by an external voltage instead of the on-board target
regulator. When the Voltage Off (
VOFF
) pin is shorted to ground (
GND
) the on-board debugger firmware
disables the target regulator, and it is safe to apply an external voltage to the VTG pin.
WARNING
Applying an external voltage to the VTG pin without shorting
VOFF
to
GND
may cause
permanent damage to the kit.
WARNING
Absolute maximum external voltage is 5.5V for the on-board level shifters, and the standard
operating condition of the ATtiny1607 is 1.8-5.5V. Applying a higher voltage may cause
permanent damage to the kit.
Programming, debugging, and data streaming is still possible with an external power supply: The
debugger and signal level shifters will be powered from the USB cable. Both regulators, the debugger,
and the level shifters are powered down when the USB cable is removed.
3.3.3
VBUS Output Pin
ATtiny1607 Curiosity Nano has a VBUS output pin which can be used to power external components that
need a 5V supply. The VBUS output pin has a PTC fuse to protect the USB against short circuits. A side
ATtiny1607 Curiosity Nano
Curiosity Nano
©
2019 Microchip Technology Inc.
User Guide
DS50002897A-page 11
