Texas Instruments TPS79301EVM, Руководство пользователя

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TPS793xx Family of LDO Regulators
1-2 Introduction
1.1 TPS793xx Family of LDO Regulators
Like all LDO linear regulators, the TPS793xx family of LDO regulators use a
series pass element and feedback network, including an error amplifier and
voltage reference, to provide a regulated output voltage from a slightly higher,
possibly varying input voltage. However, these regulators have been
optimized to reduce ripple and noise on the output. For example, advanced
feedback compensation techniques were used to increase the bandwidth and
open loop gain of the feedback network while maintaining stability with any
2.2-
µ
F ceramic capacitor. Since PSRR is directly proportional to the frequency
response of the loop of the error amplifier, these regulators’ higher loop gain
and larger bandwidth result in better PSRR over a wider range of frequencies
than standard regulators. In addition to circuit design optimization to reduce
circuit noise, the primary contributor to the noise of any regulator, the bandgap
reference, has been pinned out to allow further noise reduction through the
use of a filtering capacitor. Capabilities of this regulator include:
-
200-mA load current
-
TPS793xx family is available in 1.8-V, 2.5 V, 2.8 V, 2.85 V, 3.0 V, 3.3-V,
4.75-V, and adjustable with positive ENABLE.
-
PSRR of 75 dB at 10 kHz
-
Approximately 30-
µ
V output noise
-
Start-up in approximately 60
µ
s
-
Excellent line and load transient responses
-
Very low dropout voltage
-
5-Pin SOT23 (DBV) package to minimize board space consumption
1.2 EVM Design Strategy
The purpose of this EVM is to facilitate evaluation of the TPS793xx family of
LDO regulators. Each EVM package contains one SLVP191 test board, with
either a TPS79301DBV linear regulator or a TPS79328DBV linear regulator,
as well as supporting passive components. The TPS79301DBV adjustable
device has been configured to provide 1.5-V output, and the TPS79328DBV
provides a 2.8-V output. The board’s small size and side clips facilitate
attaching it to other PCBs as a power module.
The board has additional passive components that can be configured to test
other SOT–23 packaged regulators with the same pin-out.