TPS54122 Datasheet, PDF (1/40 Pages) Texas Instruments – Dual-Output, 3-A, QuietSupply With Integrated DC-DC Converter and Low-Noise LDO

Product
Folder
Sample &
Buy
Technical
Documents
Tools &
Software
Support &
Community
TPS54122
SBVS221B – NOVEMBER 2013 – REVISED AUGUST 2016
TPS54122 Dual-Output, 3-A, QuietSupply™
With Integrated DC-DC Converter and Low-Noise LDO
1 Features
•1 Input Voltage Range:
– VIN: 2.95 V to 6 V
– LDOIN: V_OUT + V_DO to 5.5 V
– BIAS: 2.375 V to 5.5 V
• Provides Two Configurable Supply Rails
• Independent Enable, Power Good, and Soft-Start
• 3-A, High-Efficiency, Synchronous, Step-Down
Switcher:
– Output Voltage Adjustable Down to 0.8 V
– Sync to External Clock: 300 kHz to 2 MHz
– 1% Reference Accuracy
• 3-A, Low-Noise LDO:
– Output Noise: 17 µV_RMS at 10 Hz to 1 MHz
with DC-DC Running
– Output Voltage Range: 0.8 V to 3.6 V
– Ultra-Low Dropout: 100 mV at 3 A (Typical)
– 1% Output Accuracy
– Excellent Load and Line Transient Response
• Small Package: 5.50 mm × 3.50 mm VQFN-24
3 Description
The TPS54122 device combines the efficiency of a
step-down switching (dc-dc) converter with a high
power-supply rejection (PSR), low-noise, low-dropout
regulator (LDO) to provide an ultralow-noise power
supply that delivers QuietSupply rails to noise-
sensitive applications.
The TPS54122 device is ideally suited for systems
with 5-V power busses and can support 3-A
continuous output current on both the dc-dc or LDO
output. The LDO output voltage can be set from 0.8 V
to 3.6 V and the dc-dc can be adjusted from 0.83 V to
5.0 V using external resistors. The TPS54122 device
can be used in a wide range of low-noise applications
because the dc-dc converter and LDO are completely
configurable. In addition, the TPS54122 device
includes features such as soft-start, switching
frequency synchronization, and a power-good signal.
The TPS54122 device can also be configured as a
dual-supply rail device, supplying a total of 3 A.
The TPS54122 device is available in a space-saving,
3.50 mm × 5.50 mm VQFN package, and is specified
to operate over a –40°C to +125°C ambient
temperature range.
2 Applications
• Telecom Infrastructure
• Pico and Femto Base Stations
• Powering Sensitive Clocking-Distribution Circuits
• Test and Measurement
• Powering RF Components: VCOs, Receivers,
ADCs
• Professional Audio
Device Information⁽¹⁾
PART NUMBER
PACKAGE
BODY SIZE (NOM)
TPS54122
VQFN (24)
5.50 mm × 3.50 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Application Circuit
12 V
3.3 V
DC-DC
TPS54122
Battery
VIN (DC-DC)
DC-DC Output ^{1.2 V} VCORE
Microprocessor
LDOIN
LDO Output ^{1.8 V} VCCIO
3.3 V
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.