l4949eptr-e STMicroelectronics, l4949eptr-e Datasheet - Page 11

• Manufacturer Part Number: l4949eptr-e
• Description: Multifunction Very Low Drop Voltage Regulator
• Manufacturer: STMicroelectronics

L4949ED-E, L4949EP-E
3.3
present functions are required. The modular approach of this device allows to get easily also
other features and functions when required.
Voltage regulator
The voltage regulator uses an Isolated Collector Vertical PNP transistor as a regulating
element.
Figure 4.
With this structure very low dropout voltage at currents up to 100mA is obtained. The
dropout operation of the standby regulator is maintained down to 3V input supply voltage.
The output voltage is regulated up to the transient input supply voltage of 40V. With this
feature no functional interruption due to overvoltage pulses is generated. The typical curve
showing the standby output voltage as a function of the input supply voltage is shown in
Figure
To reduce the quiescent current peak in the undervoltage region and to improve the
transient response in this region, the dropout voltage is controlled, the quiescent current as
a function of the supply input voltage is shown in
5. The current consumption of the device (quiescent current) is less than 300 µA.
Foldback characteristic of V
Doc ID 16823 Rev 1
O
Figure
6.
Application information
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