Datasheet

Data Sheet 2 Rev. 1.7, 2011-01-20
TLE 4274
Dimensioning Information on External Components
The input capacitor C
I
is necessary for compensating line influences. Using a resistor of
approx. 1 Ω in series with C
I
, the oscillating of input inductivity and input capacitance can
be damped. The output capacitor C
Q
is necessary for the stability of the regulation circuit.
Stability is guaranteed at values
C
Q
≥ 22 μF and an ESR of ≤ 3 Ω within the operating
temperature range.
Circuit Description
The control amplifier compares a reference voltage to a voltage that is proportional to the
output voltage and drives the base of the series transistor via a buffer. Saturation control
as a function of the load current prevents any oversaturation of the power element. The
IC also includes a number of internal circuits for protection against:
• Overload
• Overtemperature
• Reverse polarity