TLE4260 Datasheet, PDF (3/14 Pages) Siemens Semiconductor Group – 5-V Low-Drop Voltage Regulator

TLE 4260
Circuit Description
The control amplifier compares a reference voltage, which is kept highly accurate by
resistance adjustment, 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 over-saturation of the power element. If the output voltage goes
below 96% of its typical value, an external capacitor is discharged on pin 4 by the reset
generator. If the voltage on the capacitor reaches the lower threshold V_ST, a reset signal
is issued on pin 2 and not cancelled again until the upper threshold V_DT is exceeded. For
an output current of less than I_{QN Off} = 10 mA the standby changeover turns off the reset
generator. The latter is turned on again when the output current increases, the output
voltage drops below 4.2 V or the delay capacitor is discharged by external measures.
The IC also incorporates a number of internal circuits for protection against:
• Overload
• Overvoltage
• Overtemperature
• Reverse polarity
Overvoltage
Monitoring
Input ¹
Adjustment
Temperature
Sensor
Saturation
Control and
Protection
Circuit
BANDGAP
Reference
Control
Amplifier
+
-
Buffer
STANDBY
Changeover
7 _Output
RESET
Generator
4 RESET
Delay
2 _RESET
3
GND
Block Diagram
Semiconductor Group
3
AEB00578
1998-11-01