tb7102af TOSHIBA Semiconductor CORPORATION, tb7102af Datasheet - Page 8

• Manufacturer Part Number: tb7102af
• Description: Buck Dc-dc Converter Ic
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Undervoltage Lockout (UVLO)
voltage (V
the switch turns on, if V
Thermal Shutdown (TSD)
(160°C typ.), the TB7102AF goes into thermal shutdown and shuts off the power supply. TSD has a hysteresis of
about 20°C. The device is enabled again when the junction temperature has dropped by approximately 20°C from
the TSD trip point. The device resumes the power supply when the soft-start circuit is used upon recovery from
the TSD state .
that the TSD circuit will not be activated during normal operation of the system.
The TB7102AF has undervoltage lockout (UVLO) protection circuitry. The TB7102AF does not provide output
The TB7102AF provides thermal shutdown. When the junction temperature continues to rise and reaches T
Thermal shutdown is intended to protect the device against abnormal system conditions. It should be ensured
OUT
) until the input voltage has reached V
V
V
GND
GND
GND
OUT
OUT
V
T
IN
0
j
TSD Detection threshold: T
IN
Switching operation stops
drops below V
Figure 4 Undervoltage Lockout Operation
Switching operation stops
Figure 5 Thermal Shutdown Operation
detection voltage: V
Undervoltage lockout
UV
SD
(2.4 V typ.), UVLO shuts off the switch at V
UVR
8
UV
recovery voltage: V
Undervoltage lockout
(2.5 V typ.). UVLO has hysteresis of 0.1 V (typ.). After
Recovery from TSD
Switching operation starts
Soft start
Soft start
Switching operation starts
Hysteresis: ΔT
Hysteresis: ΔV
UVR
SD
UV
OUT
.
TB7102AF
2008-05-22
SD