TLE6368 Datasheet, PDF (8/58 Pages) Infineon Technologies AG – Multi-Voltage Processor Power Supply

TLE 6368 / SONIC
2
Detailed circuit description
In the following major buck regulator blocks, the linear voltage regulators and trackers,
the undervoltage reset function, the watchdog and the SPI are described in more detail.
For applications information e.g. choice of external components, please refer to section
5.
2.1 Buck Regulator
The diagram below shows the internal implemented circuit of the Buck converter, i. e. the
internal DMOS devices, the regulation loop and the other major blocks.
5V
Int. voltage
regulator
FB/L_IN
C+
Int. charge
pump
14V
150µA
8 to 10V
CCP
C-
BOOT-
STRAP
IN
to
current sense
amplifier
Main switch ON/OFF
SW
Gate driver
under-
voltage
lockout
Main
DMOS
IN
Divider
Oscillator
1.4MHz
Vref=6V
Voltage
feedback
amplifier
from
Current
current sensing
sense
amplifier
Lowpass
Lowpass
+
SLEW
Slope
control
switching frequency 330kHz
Slope
compensation
Gate off signal
from overtemp or
sleep command
Trigger for
gate on
Current
comparator
PWM logic
Trigger for
gate off
Slope switch
charge signal
Slope switch
discharge signal
Slope logic
Zero cross
detection
Delay unit
external components
pins
Slope
DMOS
BOOST
SW
Figure 3 Detailed Buck regulator diagram
The 1.5A Buck regulator consists of two internal DMOS power stages including a current
mode regulation scheme to avoid external compensation components plus additional
blocks for low EME and reduced switching loss. Figure 3 indicates also the principle how
Data Sheet, Rev. 1.32
8
2004-10-15