RT3605BE
Operation
rises due to output voltage droop. Then rising COMP
G-NAVP
TM
Control Mode
TM
The RT3605BE adopts G-NAVP
(Green Native AVP)
which is Richtek’s proprietary topology. It is derived from
current mode constant on-time control with finite DC gain
of error amplifier and DC offset cancellation. The topology
can achieve easy loadline design and provide high DC
accuracy and fast transient response. When sensed
current signal reaches sensed voltage signal, the
RT3605BE generates a PWM pulse to achieve loop
modulation. Figure 1 shows the basic G-NAVP
TM
behavior
waveforms. The COMP signal is the sensed voltage that
is inverted and amplified signal of output voltage. While
current loading is increasing, referring to Figure 1, COMP
Steady State
forces PWM turn on earlier and closely. While inductor
current reaches loading current, COMP enters another
steady state of higher voltage and the corresponding
output voltage is in the steady state of lower voltage. The
loadline, output voltage drooping by an amount which is
proportional to loading current, is achieved.
Load Transient
Loading Current
ΔIcc
V
OUT
VID
ΔI
cc
x R
LL
Sensed Current Signal
COMP
PWM
Figure 1. G-NAVP
TM
Behavior Waveform
Copyright
©
2019 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS3605BE-00
December 2019
www.richtek.com
7
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
