Texas Instruments 8-A DC/DC Converter with Simultaneous Sequencing of Multiple Voltages TPS54880EVM TPS54880EVM Datenbogen
Produktcode
TPS54880EVM
A-2
Figure A-2. Input Voltage Ripple (Ch.2),Sync Signal (Ch.3) and Switching Waveforms of
Core Regulator (Ch.4) and I/O Regulator (Ch.1)
In many cases, this low frequency harmonic does not affect on overall perfor-
mance of system. However, by synchronizing both switching regulators out of
phase, it is possible to avoid the beating effect and to save some input capaci-
tors because of ripple cancellation effect. This optional synchronization circuit
is implemented into TPS54x80EVM-228. It includes the following parts shown
separately in Figure 4-1: C1, R1, R4, R5, D1, Q1. This circuit takes the phase
signal of core regulator U2 as its input, inverts this signal and synchronizes the
I/O regulator U1 out of phase of regulator U2. The related waveforms are
shown in Figure A-2.
mance of system. However, by synchronizing both switching regulators out of
phase, it is possible to avoid the beating effect and to save some input capaci-
tors because of ripple cancellation effect. This optional synchronization circuit
is implemented into TPS54x80EVM-228. It includes the following parts shown
separately in Figure 4-1: C1, R1, R4, R5, D1, Q1. This circuit takes the phase
signal of core regulator U2 as its input, inverts this signal and synchronizes the
I/O regulator U1 out of phase of regulator U2. The related waveforms are
shown in Figure A-2.
The comparison of input voltage ripple for synchronized and nonsynchronized
regulators is shown in Figure A-3 and Figure A-4 respectively
regulators is shown in Figure A-3 and Figure A-4 respectively