RT6210
Application Information
Output Voltage Setting
The output voltage can be adjusted by setting the feedback
resistors R1 and R2, as Figure 1. Choose a 10kΩ resistor
for R2 and calculate R1 by using the equation below :
R1
UVLO
V
IN
VOUT VFB (1 +
)
R2
where VFB is the feedback voltage (typically equal to VREF
V
EN
)
3V
V
OUT
V
REF
R1
FB
V
SS
RT6210
GND
R2
V
OUT
Figure 1. Output Voltage Setting by a Resistive Voltage
Divider
V
SW
Chip Enable Operation
Normal Operation with
pulse skipping mode
Soft-Start
Delay time
Soft-Start
The RT6210 provides enable/disable control through the
EN pin. The chip remains in shutdown mode by pulling
the EN pin below Logic-Low threshold (0.875V). During
the shutdown mode, the RT6210 disables most of the
logic circuitry to lower the quiescent current. When VEN
rises above Logic-High threshold (VTH_EN 1.3V), the
RT6210 will begin initialization for a new soft-start cycle.
Figure 2. Power-Up Sequence Controlled by the EN Pin
UVLO
V
IN
If the EN pin is floating, VEN will be pulled Low by a 1μA
current drawn from the EN pin. Connecting a 1kΩ to 100kΩ
pull-up resistor is recommended. An external MOSFET
can be added to implement a logic-controlled enable
control. Figure 2 shows the power up sequence, which is
controlled by the EN pin.
V
EN
3V
V
REF
The RT6210 also provides enable control through VIN pin.
If the VEN is above Logic-High threshold first, the chip will
V
SS
remain in shutdown mode until the VIN rises above VUVLO
.
Figure 3 shows the power up sequence, which is controlled
by the VIN pin.
V
OUT
V
SW
Normal Operation with
pulse skipping mode
Soft-Start
Delay time
Soft-Start
Figure 3. Power-Up Sequence Controlled by the VIN Pin
Copyright 2019 Richtek Technology Corporation. All rights reserved.
©
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
12
DS6210-01 February 2019
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
