S-19253E12H-U5T1U Datasheet, PDF (10/30 Pages) Seiko Instruments Inc – CMOS VOLTAGE REGULATOR WITH SOFT-START FUNCTION

FOR AUTOMOTIVE 105°C OPERATION LOW DROPOUT HIGH OUTPUT CURRENT CMOS VOLTAGE REGULATOR WITH SOFT-START FUNCTION
S-19253xxxH Series
Rev.1.0_00
 Standard Circuit
Input
VIN
VOUT
Output
C_IN^*1
ON / OFF ^SSC
C_SS^*3
C_L^*2
VSS
Single GND
*1. C_IN is a capacitor for stabilizing the input.
*2. C_L is a capacitor for stabilizing the output.
*3. C_SS is a capacitor for soft-start.
Figure 9
GND
Caution The above connection diagram and constants will not guarantee successful operation. Perform
thorough evaluation including the temperature characteristics with an actual application to set the
constants.
 Condition of Application
Input capacitor (C_IN): A ceramic capacitor with capacitance of 2.2 μF or more is recommended.
Output capacitor (C_L): A ceramic capacitor with capacitance of 2.2 μF or more is recommended.
Caution Generally, in a voltage regulator, an oscillation may occur depending on the selection of the external
parts. Perform thorough evaluation including the temperature characteristics with an actual
application using the above capacitors to confirm no oscillation occurs.
 Selection of Input Capacitor (C_IN) and Output Capacitor (C_L)
The S-19253xxxH Series requires C_L between the VOUT pin and the VSS pin for phase compensation. The operation
is stabilized by a ceramic capacitor with capacitance of 2.2 μF or more. When using an OS capacitor, a tantalum
capacitor or an aluminum electrolytic capacitor, the capacitance also must be 2.2 μF or more. However, an oscillation
may occur depending on the equivalent series resistance (ESR).
Moreover, the S-19253xxxH Series requires C_IN between the VIN pin and the VSS pin for a stable operation.
Generally, an oscillaiton may occur when a voltage regulator is used under the conditon that the impedance of the
power supply is high.
Note that the output voltage transient characteristics varies depending on the capacitance of C_IN and C_L and the value
of ESR.
Caution Perform thorough evaluation including the temperature characteristics with an actual application to
select C_IN and C_L.
 Selection of Capacitor for Soft-start (C_SS)
The S-19253xxxH Series requires the capacitor for soft-start (C_SS) between the SSC pin and the VSS pin. Over the
entire temperature range, the S-19253xxxH Series operates stably with a ceramic capacitor of 0.68 nF or more.
According to C_SS capacitance, the rising speed of the output voltage is adjustable. The time that the output voltage
rises to 99% is 6.0 ms typ. at C_SS = 10 nF. The recommended value for applications is 0.68 nF ≤ C_SS ≤ 168 nF,
however; define the values by sufficient evaluation including the temperature characteristics under the usage
condition.
10