TLD5098EL Datasheet, PDF (19/39 Pages) Infineon Technologies AG – DC/DC Boost, Buck-Boost, SEPIC controller

TLD5098EL
Linear Regulator
8
Linear Regulator
8.1
Description
The internal linear voltage regulator supplies the internal gate drivers with a typical voltage of 5V and current up
to I_LIM,min (Parameter 8.2.2). An external output capacitor with ESR lower than R_IVCC,ESR (Parameter 8.2.5) is
required on pin IVCC for stability and buffering transient load currents. During normal operation the external boost
and dimming MOSFET switches will draw transient currents from the linear regulator and its output capacitor.
Proper sizing of the output capacitor must be considered to supply sufficient peak current to the gate of the
external MOSFET switches.
Integrated undervoltage protection for the external switching MOSFET:
An integrated undervoltage reset threshold circuit monitors the linear regulator output voltage (V_IVCC) and resets
the device in case the output voltage falls below the IVCC Undervoltage Reset switch OFF Threshold (V_IVCC,RTH,d
Parameter 8.2.7). The Undervoltage Reset threshold for the IVCC pin helps to protect the external switches from
excessive power dissipation by ensuring the gate drive voltage is sufficient to enhance the gate of an external logic
level N-channel MOSFET.
IN
14
EN / PWMI ¹³
Linear Regulator
IVCC
1
Gate
Drivers
Figure 8 Voltage Regulator Block Diagram and Simplified Application Circuit
Datasheet
19
Rev. 1.0, 2010-10-13