TLE 8386-2EL Infineon Technologies, TLE 8386-2EL Datasheet - Page 23

• Manufacturer Part Number: TLE 8386-2EL
• Manufacturer: Infineon Technologies

Specifications of TLE 8386-2EL

• Packages: PG-SSOP-14
• Comment: LS-sense-booster (prefered as voltage source);Can be used in SEPIC- or FLYBACK-configuration as wellMax. output current dependent on output voltage.
• Vq (max): adj (max 9-times of VS)
• Iq (max): -
• Iq (typ): 7,000.0 µA
• Output: Boost Converter

Current sense resistor R
For control and protection, the TLE8386-2EL measures the power MOSFET current by a current sense resistor
R
•
•
•
•
•
The figure below shows the voltage waveform over the current sense resistor R
Figure 10
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•
•
The maximum (peak-to-peak) switch current ripple percentage (will be needed for further calculations of inductor
values) can be calculated considering the 20% margin by following equation:
•
•
Data Sheet
CS
To locate the current sense resistor as close as possible to the TLE8386-2EL
To use short (low resistive and low inductive) traces between the power MOSFET source and ground.
To use short (low resistive and low inductive) traces between the current sense resistor R
lowside and the pins SWCS and SGND (it is not recommended to use pin GND instead of pin SGND for power
MOSFET current measurement).
The value of R
steady state normal operation will be lower than the adjusted current limit threshold (current limit function!). It
is recommended to give a 20% margin.
The value of R
not be exceeded (please refer to power MOSFET data sheet).
V
V
current in the boost inductor L
V
, which is located between the power MOSFET source and ground. For proper function it is very important:
V
SENSEMAX
SENSEPEAK
SWCS
is recommended to fall in the range between 0.2 to 0.6 (please refer to calculations in the following chapters)
SENSE
= Switch peak over current threshold
= ripple voltage across R
Sense voltage V
= maximum average sense voltage at maximum output current I
= maximum peak sense voltage at maximum output current I
CS
CS
V
should be selected to make sure that the maximum peak sense voltage V
should be selected to make sure that the power MOSFET maximum drain current I
SENSE
CS
selection:
SENSE
On-Time
V
SENSEMAX
BOOST
waveform during a switching cycle
=
CS
.
-------------------------------------------------------------------------------- -
0 80
(switch ripple current) during on-time, represents the peak-to-peak ripple
,
Switching Cycle
V
V
SENSEPEAK
SWCS
∆V
SENSE
V
21
–
SENSE
0 50
,
V
SENSE
BO
BO
at end of on-time.
CS
measured during on-time.
during a switching cycle:
t
Application Information
Rev. 1.0, 2010-10-25
CS
SENSEPEAK
TLE8386-2EL
highside and
DMAX
during
will