s-8521b51mc-aukt2g Seiko Instruments Inc., s-8521b51mc-aukt2g Datasheet - Page 21

• Manufacturer Part Number: s-8521b51mc-aukt2g
• Description: Step-down, Pwm Control Or Pwm / Pfm Switchable Switching Regulator Controller
• Manufacturer: Seiko Instruments Inc.

Rev.8.3
Standard Circuits
1. Using a bipolar transistor
2. Using a Pch MOS FET transistor
Caution The above connection diagram and constant will not guarantees successful operation.
STEP-DOWN, PWM CONTROL or PWM / PFM SWITCHABLE SWITCHING REGULATOR CONTROLLOR
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Perform through evaluation using the actual application to set the constant.
V
V
IN
IN
+
+
C
C
IN
IN
R
b
SD
Tr
ON
Tr
SD
ON
C
/
b
OFF
/
OFF
EXT
VIN
EXT
VIN
Seiko Instruments Inc.
Figure 12
Figure 13
Oscillation
PWM control or
PWM/PFM switching
cotrol circuit
PWM control or
PWM/PFM switching
control circuit
Oscillation
circuit
circuit
VSS
VSS
source with soft start
source with soft start
Reference voltage
Reference voltage
L
L
V
V
ON
ON
/
/
OFF
OF F
+
−
+
−
VOUT
S-8520 / 8521 Series
VOUT
+
C
+
C
OUT
OUT
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