S1F78100Y2A Epson Electronics America, Inc., S1F78100Y2A Datasheet - Page 70

• Manufacturer Part Number: S1F78100Y2A
• Description: High Precision Voltage Regulators
• Manufacturer: Epson Electronics America, Inc.

Changing the temperature coefficient:
Application notes on voltage regulator circuit:
S1F70000 Series
Technical Manual
• The temperature coefficient of the regulated voltage depends on the temperature coefficient of the reference
• To satisfy the absolute maximum ratings of the S1F76540, the setup resistor(s) must be inserted between V
• The regulation voltage adjustment input (pin RV) has the very high input impedance, and its noise insertion can
voltage (if the division ratio of setup resistors does not depend on the temperature). It is necessary to change the
temperature coefficient using thermistors, resistors or others to set any other temperature coefficient of the
regulated voltage. The following explains how to calculate the V
If the temperature coefficient of R1 and R2 is identical in equation (3), the V
perature coefficient of internal reference voltage only.
and V
destroyed if the R1 resistor is connected to pin V
connection.
drop the regulator stability. As shown in Figure 2.5, shield the cable between the division resistor and RV pin or
use a cable as short as possible between them.
V
REG
T
C
C
C
R1 (T
R2 (T
V
0
TR1
TR2
T
REF
REG
(T) = 1 +
0
0
(T
)
)
pins of the S1F76540 that uses the voltage regulator. The S1F76540 IC itself may be degraded or
0
) : Internal reference voltage (V) at 25 C
{
: 25 C
: Temperature coefficient of resistor R1 (Ratio to the value at 25 C)
: Temperature coefficient of resistor R2 (Ratio to the value at 25 C)
: Temperature coefficient of internal reference voltage (%/ C)
: R1 value ( ) at 25 C
: R2 value ( ) at 25 C
C
C
TR2
TR1
R2 (T
R1 (T
0
0
)
)
}
[
1+ (T – T
EPSON
DD
0
)
of S1F76540 that does not use the regulator during serial
100
C
T
]
REG
voltage in temperature T.
REG
• • • • Equation (3)
voltage depends on the tem-
S1F76540 Series
2–27
DD