R16AN0002EU0300 Rev.3.00
Page 6
Jan 6, 2022
ISL9241 Operation Modes Application Note
1.5
Supplemental Mode (Intel VAP)
Use Supplemental mode or Intel VMIN Active Protection (VAP) when the battery voltage is sufficient to provide
power to the system but the impedance from the battery to the system causes a large voltage drop, limiting the
power that can be drawn without crashing the system. This mode also supports rare peak power events that are
higher than what the battery power can support. Use this mode when there is only a battery in the system and the
adapter port is open.
When the battery voltage is high, the ISL9241 operates in reverse direction (OTG mode) and stores some energy
from the battery in the input capacitors (on the adapter side) at high voltage.
If the system voltage starts falling below a threshold during a high system load event due to high battery
impedance or low battery voltage, the energy from the input capacitor supplements the battery power and holds
up the system voltage until the load event ends.
After receiving the command to exit the mode, the energy stored in the input capacitors can be discharged using
an internal discharge path so that an external power source can be safely connected.
This mode’s setup can be controlled by an external microcontroller or host controller on the system. Several
parameters can be programmed to achieve the needed response from the ISL9241.
Figure 5. Supplemental Mode (Intel VMIN Active Protection)
System
Power
Battery
Mode
Power
Switch
is
ON
OTG
for
Stored
Power
Stored
Power
on
Capacitor
