ep5368 Enpirion, ep5368 Datasheet - Page 9

• Manufacturer Part Number: ep5368
• Description: 600ma Synchronous Buck Regulator With Integrated Inductor
• Manufacturer: Enpirion

April 2008
External Voltage Divider
As described above, the external voltage
divider option is chosen by connecting the
VS0, VS1, and VS2 pins to VIN or logic “high”.
The EP5368QI uses a separate feedback pin,
V
must be connected to V
Figure 4.
Figure 4. External Divider application circuit.
The output voltage is selected by the following
formula:
R
gain. Then R
V
0.603V to V
Dynamically Adjustable Output
The EP5368QI is designed to allow for
dynamic switching between the predefined VID
voltage levels The inter-voltage slew rate is
optimized to prevent excess undershoot or
overshoot
transition. The slew rate is identical to the soft-
start slew rate of 1.5V/mS.
Dynamic transitioning between internal VID
settings and the external divider is not allowed.
©Enpirion 2008 all rights reserved, E&OE
V
R
V
FB
OUT
OUT
a
b
IN
must be chosen as 200K Ω to maintain loop
=
, when using the external divider. VSENSE
V
4.7uF
=
0603
. 1
can be programmed over the range of
OUT
. 0
206
603
−
x
. 0
10
IN
V
603
as
b
5
-0.4V.
(
1
V
V
V
ENABLE
is given as:
S0
S1
S2
V
Ω
+
in
EP5368QI
Ra
Rb
the
)
GND
output
V
Sense
OUT
V
V
out
FB
as indicated in
Ra
Rb
voltage
levels
V
22µF
0805
OUT
9
Input and Output Capacitors
The input capacitance requirement is 4.7uF
0603 MLCC. The input capacitor must be a
X5R/X7R MLCC. Y5V or equivalent dielectric
formulations lose capacitance with frequency,
bias, and with temperature, and are not
suitable for switch-mode DC-DC converter
input filter applications.
The
approximately 20uF. Enpirion recommends a
single 22uF 0805 MLCC. Ripple performance
can be improved by using 2 x 10uF 0805 MLC
capacitors.
The output capacitor must be a X5R/X7R or
equivalent MLCC. Y5V or equivalent dielectric
formulations lose capacitance with frequency,
bias, and temperature and are not suitable for
switch-mode DC-DC converter output filter
applications.
Please consult Enpirion Applications Support
for other capacitor case size combinations.
Operation at 700mA Output Current
Operation at 700mA is supported by using the
application circuit shown in Figure 5.
modification in the compensation is to ensure
stability over the entire set of input and output
voltage conditions.
Figure 5. Applications circuit for operation at 700mA.
V
IN
4.7uF
0603
output
V
V
V
ENABLE
V
S0
S1
S2
in
capacitance
EP5368QI
GND
www.enpirion.com
V
Sense
V
V
out
FB
requirement
Ra
Rb
EP5368QI
C
a
V
22µF
0805
The
OUT
is