Texas Instruments TPS54560 Step-Down DC-DC Converter Evaluation Module TPS54560EVM-515 TPS54560EVM-515 Datenbogen
Produktcode
TPS54560EVM-515
SW
VIN
GND
BOOT
FB
COMP
TPS54560
EN
RT/CLK
Cpole
Czero
Rcomp
RT
Co
Lo
Cboot
Cin
R1
R2
Cd
VIN
VOUT
+
+
GND
SLVSBN0A – MARCH 2013 – REVISED MARCH 2014
8.4 Device Functional Modes
8.4.1 Operation with V
IN
< 4.5 V (Minimum V
IN
)
The device is recommended to operate with input voltages above 4.5 V. The typical VIN UVLO threshold is 4.3 V
and the device may operate at input voltages down to the UVLO voltage. At input voltages below the actual
UVLO voltage, the device will not switch. If EN is externally pulled up to V
and the device may operate at input voltages down to the UVLO voltage. At input voltages below the actual
UVLO voltage, the device will not switch. If EN is externally pulled up to V
IN
or left floating, when V
IN
passes the
UVLO threshold the device will become active. Switching is enabled the soft start sequence is initiated. The
TPS54560 will start at the soft start time determined by the internal soft start time.
TPS54560 will start at the soft start time determined by the internal soft start time.
8.4.2 Operation with EN Control
The enable threshold voltage is 1.2 V typical. With EN held below that voltage the device is disabled and
switching is inhibited even if V
switching is inhibited even if V
IN
is above its UVLO threshold. The IC quiescent current is reduced in this state. If
the EN voltage is increased above the threshold while V
IN
is above its UVLO threshold, the device becomes
active. Switching is enabled, and the soft start sequence is initiated. The TPS54560 will start at the soft start time
determined by the internal soft start time.
determined by the internal soft start time.
8.4.3 Alternate Power Supply Topologies
8.4.3.1 Inverting Power
The TPS54560 can be used to convert a positive input voltage to a negative output voltage. Idea applications are
amplifiers requiring a negative power supply. For a more detailed example see
amplifiers requiring a negative power supply. For a more detailed example see
Figure 35. TPS54560 Inverting Power Supply from
Application Note
22
Copyright © 2013–2014, Texas Instruments Incorporated
Product Folder Links: