tcv7102af TOSHIBA Semiconductor CORPORATION, tcv7102af Datasheet - Page 8

• Manufacturer Part Number: tcv7102af
• Description: Buck Dc-dc Converter Ic
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Usage Precautions
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Thermal Shutdown (TSD)
T
hysteresis of about 15°C (typ.). The device is enabled again when the junction temperature has dropped by
approximately 15°C from the TSD trip point. The device resumes the power supply when the soft-start circuit is
activated upon recovery from TSD state.
that the TSD circuit will not be activated during normal operation of the system.
The input voltage, output voltage, output current and temperature conditions should be considered when
selecting capacitors, inductors and resistors. These components should be evaluated on an actual system
prototype for best selection.
Parts of this product in the surrounding are examples of the representative, and the supply might become
impossible. Please confirm latest information when using it.
External components such as capacitors, inductors and resistors should be placed as close to the TCV7102AF as
possible.
The TCV7102AF has an ESD diode between the EN and V
satisfy V
C
to board layout. In that case, add a decoupling capacitor (C
The minimum programmable output voltage is 0.8V (typ.). If the difference between the input and output
voltages is small, the output voltage might not be regulated accurately and fluctuate significantly.
When TCV7102AF is in operation, a negative voltage is generated since regeneration current flows through the
switch pin (L
transistor, operation is undisturbed so an external flywheel diode is unnecessary. If there is the possibility of an
external negative voltage generation, add a diode for protection.
SGND pin is connected with the back of IC chip and serves as the heat radiation pin. Secure the area of a GND
pattern as large as possible for greater of heat radiation.
The overcurrent protection circuits in the Product are designed to temporarily protect Product from minor
overcurrent of brief duration. When the overcurrent protective function in the Product activates, immediately
cease application of overcurrent to Product. Improper usage of Product, such as application of current to Product
exceeding the absolute maximum ratings, could cause the overcurrent protection circuit not to operate properly
and/or damage Product permanently even before the protection circuit starts to operate.
The thermal shutdown circuits in the Product are designed to temporarily protect Product from minor
overheating of brief duration. When the overheating protective function in the Product activates, immediately
correct the overheating situation. Improper usage of Product, such as the application of heat to Product
exceeding the absolute maximum ratings, could cause the overheating protection circuit not to operate properly
and/or damage Product permanently even before the protection circuit starts to operate.
SD
IN
The TCV7102AF provides thermal shutdown. When the junction temperature continues to rise and reaches
Thermal shutdown is intended to protect the device against abnormal system conditions. It should be ensured
should be connected as close to the PGND and V
(150°C typ.), the TCV7102AF goes into thermal shutdown and shuts off the power supply. TSD has a
EN
− V
X
). Even if the current flows through the low side parasitic diode during the dead time of switching
IN2
V
< 0.3V.
GND
OUT
T
0
j
Figure 6 Thermal Shutdown Operation
Switching operation stops
temperature: T
TSD detection
SD
IN1
8
pins as possible. Operation might become unstable due
IN2
C
) of 0.1 μF to 1μF between the SGND and V
pins. The voltage between these pins should
Recovery from TSD
Soft start
Switching operation starts
Hysteresis: ΔT
SD
TCV7102AF
2011-06-23
IN2
pins.