Figure 3-1. Curiosity Nano Standard Pinout
USB
DEBUGGER
PS LED
NC
NC
ID
ID
CDC RX
CDCRX
CDC TX
CDCTX
DBG1
DBG1
DBG2
DBG2
VBUS
VBUS
VOFF
VOFF
DBG3
DBG3
DBG0
DBG0
GND
GND
VTG
VTG
CURIOSITY NANO
3.3
Power Supply
The kit is powered through the USB port and contains two LDO regulators, one to generate 3.3V for the
on-board debugger, and an adjustable LDO regulator for the target microcontroller ATtiny1607 and its
peripherals. The voltage from the USB connector can vary between 4.4V to 5.25V (according to the USB
specification) and will limit the maximum voltage to the target. The figure below shows the entire power
supply system on ATtiny1607 Curiosity Nano.
Figure 3-2. Power Supply Block Diagram
USB
Target
MCU
Power source
Cut strap
Power consumer
P3V3
DEBUGGER
Power converter
DEBUGGER
Regulator
VUSB
Target
Regulator
Power
Supply
strap
Adjust
Level
shifter
VLVL
VREG
I/O
I/O
GPIO
straps
I/O
On/Off
Measure
On/Off
ID system
#VOFF
PTC
Fuse
Power protection
VBUS
Target
Power
strap
VTG
3.3.1
Target Regulator
The target voltage regulator is a MIC5353 variable output LDO. The on-board debugger can adjust the
voltage output supplied to the kit target section by manipulating the MIC5353's feedback voltage. The
hardware implementation is limited to an approximate voltage range from 1.7V to 5.1V. Additional output
voltage limits are configured in the debugger firmware to ensure that the output voltage never exceeds
the hardware limits of the ATtiny1607 microcontroller. The voltage limits configured in the on-board
debugger on ATtiny1607 Curiosity Nano are 1.8-5.1V.
ATtiny1607 Curiosity Nano
Curiosity Nano
©
2019 Microchip Technology Inc.
User Guide
DS50002897A-page 10
