s-8426a Seiko Instruments Inc., s-8426a Datasheet - Page 21

• Manufacturer Part Number: s-8426a
• Description: Battery Backup Switching Ic
• Manufacturer: Seiko Instruments Inc.

Rev.1.0
Output
voltage
Input
voltage
Figure 37 Output Voltage Variation due to Output Current
2. Load Transient Response Based on Output Current Fluctuation
2. 1 Load Variation
Figure 39 shows the ringing waveforms at the VOUT pin and Figure 40 shows the ringing waveforms at the VRO
pin due to the load variation, respectively.
The overshoot and undershoot are caused in the output voltage if the output current fluctuates between 10 µA and
50 mA (V
variation due to the output current. Figure 38 shows the test circuit for reference. The latter half of this section
describes ringing waveform and parameter dependency.
VOUT pin
VRO pin
50 mA
_00
Output current
Output current
Output voltage
Output voltage
(50 mV/div)
(20 mV/div)
RO
is between 10 µA and 30 mA) while the input voltage is constant. Figure 37 shows the output voltage
10 µA
50 mA
30 mA
Figure 39 Ringing Waveform due to Load Variation (VOUT Pin)
Figure 40 Ringing Waveform due to Load Variation (VRO Pin)
10 µA
Overshoot
10 µA
t (500 ms/div)
t (20 ms/div)
Seiko Instruments Inc.
Undershoot
BATTERY BACKUP SWITCHING IC
VIN
S-8426A Series
V
V
IN
IN
VSS
Figure 38 Test Circuit
= 6.0 V, C
= 6.0 V, C
10 µA
10 µA
VOUT
30 mA
50 mA
OUT
RO
t (50 µs/div)
C
t (50 µs/div)
= 22 µF, Ta = 25 °C
= 22 µF, Ta = 25 °C
OUT
S-8426A Series
Oscillo
scope
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