TOBY-R2 series - System integration manual
UBX-16010572 - R10
System description
Page 25 of 151
1.5.3
Generic digital interfaces supply output (V_INT)
The V_INT output pin of the TOBY-R2 series modules is connected to an internal 1.8 V supply with
current capability specified in the TOBY-R2 series data sheet
. This supply is internally generated
by a switching step-down regulator integrated in the Power Management Unit and it is internally used
to source the generic digital I/O interfaces of the cellular module, as described in
. The output
of this regulator is enabled when the module is switched on and it is disabled when the module is
switched off.
Baseband
Processor
70
VCC
71
VCC
72
VCC
5
V_INT
Switching
Step-Down
Power
Management
TOBY-R2 series
Digital I/O
Figure 12: TOBY-R2 series generic digital interfaces supply output (V_INT) simplified block diagram
The switching regulator operates in Pulse Width Modulation (PWM) mode for greater efficiency at
high output loads and it automatically switches to Pulse Frequency Modulation (PFM) power save
mode for greater efficiency at low output loads. The V_INT output voltage ripple is specified in the
TOBY-R2 series data sheet
