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 PIC16F15376
microcontroller. The voltage limits configured in the on-board debugger on PIC16F15376 Curiosity Nano are
2.3-5.1V.
Info:
The target voltage is set to 3.3V in production. It can be changed through MPLAB X project
properties. 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 printed circuit board (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.
PIC16F15376 Curiosity Nano
Curiosity Nano
©
2019 Microchip Technology Inc.
User Guide
50002900B-page 10
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
