1 Features
1• 350-mA High-Performance LDO
• Low Quiescent Current: 38 μA
• Excellent Load Transient Response:
±15 mV for ILOAD = 0 mA to 350 mA in 1 μs
• Excellent Line Transient Response:
ΔVOUT = ±2 mV for ΔVBIAS = ±600 mV in 1 μs
ΔVOUT = ±200 μV for ΔVIN = ±400 mV in 1 μs
• Low Noise: 48 μVRMS (10 Hz to 100 kHz)
• 80 dB VIN PSRR (10 Hz to 10 kHz)
• 70 dB VBIAS PSRR (10 Hz to 10 kHz)
• Fast Start-Up Time: 140 μs
• Built-In Soft-Start With Monotonic VOUT Rise and
Start-Up Current Limited to 100 mA + ILOAD
• Overcurrent and Thermal Protection
• Low Dropout: 110 mV at ILOAD = 350 mA
• Stable with 2.2-μF Output Capacitor
• Available in 1.33 mm × 0.96 mm DSBGA-5 and 2
mm × 2 mm SON-6 Packages

2 Applications
• Digital Cameras
• Cellular Camera Phones
• Wireless LAN
• Handheld Products

3 Description
The TPS720 family of dual rail, low-dropout linear
regulators (LDOs) offers outstanding ac performance
(PSRR, load and line transient response), while
consuming a very low quiescent current of 38 μA.
The VBIAS rail that powers the control circuit of the
LDO draws very low current (on the order of the
quiescent current of the LDO) and can be connected
to any power supply that is equal to or greater than
1.4 V above the output voltage. The main power path
is through VIN, which can be a lower voltage than
VBIAS; it can be as low as VOUT + VDO, increasing the
efficiency of the solution in many power-sensitive
applications. For example, VIN can be an output of a
high-efficiency, DC-DC step-down regulator.
The TPS720 supports a novel feature in which the
output of the LDO regulates under light loads when
the IN pin is left floating. The light-load drive current
is sourced from VBIAS under this condition. This
feature is particularly useful in power-saving
applications where the DC-DC converter connected
to the IN pin is disabled but the LDO is still required
to regulate the voltage to a light load.
The TPS720 is stable with ceramic capacitors and
uses an advanced BICMOS fabrication process that
yields a dropout of 110 mV at a 350-mA output load.
The TPS720 has the unique feature of providing a
monotonic VOUT rise (overshoot limited to 3%) with
VIN inrush current limited to 100 mA + ILOAD with an
output capacitor of 2.2 μF.
The TPS720 uses a precision voltage reference and
feedback loop to achieve overall accuracy of 2% over
load, line, process, and temperature extremes. An
ultra-small DSBGA package makes the TPS720 ideal
for handheld applications. The TPS720 is also
available in a SON-8 package. This family of devices
is fully specified over the temperature range of
TJ = –40°C to 125°C.