S-882Z Datasheet, PDF (12/24 Pages) Seiko Instruments Inc – ULTRA-LOW VOLTAGE OPERATION CHARGE PUMP IC FOR STEP-UP DC-DC CONVERTER STARTUP

ULTRA-LOW VOLTAGE OPERATION CHARGE PUMP IC FOR STEP-UP DC-DC CONVERTER STARTUP
S-882Z Series
Rev.1.2_00
„ Example of Connection with Step-up DC-DC Converter
The following are the connection examples based on the set condition.
The symbols used in the connection diagram are described in Table 7 below.
Symbol
SD1
C_VDD
SD2, R_OUT
R₁, R₂
Table 7
Description
A Schottky diode for preventing a voltage decline in the VDD pin due to output capacitor C_L at
step-up DC-DC converter startup.
The power smoothing capacitor of the step-up DC-DC converter. Set the capacitance value so
that C_VDD ≤ C_CPOUT × 0.1.
A Schottky diode and pull-down resistor to prevent the OUT pin voltage of the S-882Z Series
from exceeding the absolute maximum rated voltage.
Bleeder resistors to prevent the VM pin voltage of the S-882Z Series from exceeding the
absolute maximum rated voltage.
1. V_OUT ≤ 3.0 V, C_L ≤ C_CPOUT × 0.1, no load
VIN
VOUT
CCPOUT
CPOUT
VIN
S-882Z Series
OUT
VDD
VIN
OUT
Step-up DC-DC converter
VM
CIN
VSS
VSS
CL
2. V_OUT ≤ 3.0 V, C_L > C_CPOUT × 0.1
VIN
CCPOUT
CPOUT
VIN
S-882Z Series
OUT
VM
CIN
VSS
Figure 16
SD1
CVDD
VDD
VIN
OUT
Step-up DC-DC converter
VSS
VOUT
CL
Figure 17
12
Seiko Instruments Inc.