S-8327 Seiko, S-8327 Datasheet - Page 37

• Manufacturer Part Number: S-8327
• Description: (S-8323 / S-8327) SMALL PACKAGE PWM CONTROL STEP-UP SWITCHING REGULATOR
• Manufacturer: Seiko

SMALL PACKAGE PWM CONTROL STEP-UP SWITCHING REGULATOR
S-8323/8327 Series


36
Reference Data
Use reference data to choose the external parts.
Reference data give yor the procedure to choose the recommended external parts for various applications and its
characteristics data.
1. Procedure to choose the most suitable condition from reference data.
*1)
*2)
*3)
*4)
*5)
Choose the best condition for operation efficiency.
Choose desired output voltage from conditions (1) to (17) shown in Table 1 and 2.
When desired output voltage does not exist in Tables, choose the next higher voltage.
For instance, when V
Choose all conditions from conditions choosed above for output current needed for input voltage (min) of the
operational condition from “Reference data 1 (a) output voltage characteristics for output current”.
For instance, when 10mA output current is needed at V
Stand-by efficiency means the efficiency when the output current is small (approx. 100 A), operation efficiency
means the efficiency when the output current is large (several mA).
For instance, go to “YES” when operation efficiency is more important rather than stand-by efficiency.
Read the efficiency for input voltage and output current in operational condition from “Reference data 1 (b)
efficiency characteristics for output current”.
For instance, when V
There is no difference between conditions (4) to (6) when the output current is 100 A at stand-by condition.
Therefore, choose condition (6).
Read the ripple voltage under the operational condition selected above from “Reference data 2 ripple voltage
characteristics for output current”.
For instance, when condition (6) is selected above, the ripple voltage is
Ripple voltage is OK?
Stand-by
efficiency is OK?
Yes
Yes
END
Choose the condition for desired output current
Choose the desired output voltage
Operation efficiency is
more important rather than
stand-by efficiency?
Yes
START
*4
*5
OUT
IN
=0.9V at I
No
No
=3V for S-8323, choose from conditions (3) to (6).
Choose next best
condition for operation
efficiency
Increase output
current
OUT
=10mA, the efficiency is max. (75%) in condition (6) in (4) to (6).
*3
*1
*4
Seiko Instruments Inc.
No
*5
Choose the best condition for stand-by efficiency.
*4
*2
Operation efficiency is OK?
IN
=0.9V, choose from conditions (4) to (6).
Yes
mV at V
*4
No
IN
Choose next best condition
for stand-by efficiency
=0.9V and I
*4
OUT
=10mA.
*4