Datasheet

The user can also set the 32.768 kHz crystal oscillator in Bypass mode instead of connecting a crystal. In this case,
the user has to provide the external clock signal on XIN32. The input characteristics of the XIN32 pin are given in the
section “Electrical Characteristics”. T
o enter Bypass mode, the OSCBYPASS bit in the Mode register (SUPC_MR)
must be set before setting XTALSEL.
Related Links
58. Electrical Characteristics for SAM V70/V71
59. Electrical Characteristics for SAM E70/S70
23.4.3 Core Voltage Regulator Control/Backup Low-power Mode
The SUPC controls the embedded voltage regulator.
The voltage regulator automatically adapts its quiescent current depending on the required load current. Refer to the
section “Electrical Characteristics”.
The user can switch off the voltage regulator, and thus put the device in Backup mode, by writing a ‘1’ to
SUPC_CR.VROFF.
This asserts the vddcore_nreset signal after the write resynchronization time, which lasts two slow clock cycles (worst
case). Once the vddcore_nreset signal is asserted, the processor and the peripherals are stopped one slow clock
cycle before the core power supply shuts off.
When the internal voltage regulator is not used and VDDCORE is supplied by an external supply, the voltage
regulator can be disabled by writing a ‘0’ to SUPC_MR.ONREG.
Related Links
58. Electrical Characteristics for SAM V70/V71
59. Electrical Characteristics for SAM E70/S70
23.4.4 Using Backup Batteries/Backup Supply
When backup batteries or, more generally, a separate backup supply is used, only VDDIO is present in Backup
mode. No other external supply is applied.
Figure 23-2. Separate Backup Supply Powering Scheme
Main Supply
V
DDCORE Supply
ADC, DAC
Analog Comp
.
USB
Transceivers
VDDIN
Voltage
Regulator
VDDOUT
VDDCORE
VDDIO
VDDPLL
VDDUTMIC
VDDUTMII
Note: Restrictions
With main supply < 3.0V
, USB is not usable.
With main supply < 2.7V, MediaLB is not usable.
With main supply < 2.0V, ADC, DAC and Analog comparator are not usable.
With main supply and VDDIN > 3V, all peripherals are usable.
SAM E70/S70/V70/V71 Family
Supply Controller (SUPC)
© 2019 Microchip T
echnology Inc.
Datasheet
DS60001527D-page 155