AS1355
3 0 0 m A , Tri p l e L D O
1 General Description
The AS1355 is a high-performance triple CMOS low-dropout voltage
regulator in a single QFN package. The efficient set of
programmable power supplies is optimized to deliver the best
compromise between quiescent current and regulator performance
for mobile phones, PDAs, MP3 players, and other battery powered
devices.
Stability is guaranteed with ceramic output capacitors of only 1µF
(±20% – X5R) up to 4.7µF (±20% – X5R). The low equivalent series
resistance (ESR) of these capacitors ensures low output impedance
at high frequencies.
Regulation performance is excellent even under low dropout
conditions, when the power transistor has to operate in linear mode.
The low-noise performance allows direct connection of noise
sensitive circuits without additional filtering networks.
The AS1355 is available in a 16-pin QFN 3x3 package.
Accuracy: ±1.0%
PSRR: 70dB at 1kHz, 60dB at 100kHz
Load Regulation: 3mV (0 to 300mA)
Supply Range: 2.3V to 5.5V
0.1V Dropout Voltage @ Iload = 200mA
Shutdown Current: 1µA
Supply Current Without Load: 160µA
Softstart for Low Inrush Current
Stable with low ESR Ceramic Capacitors from 1µF to 4.7µF
Low Noise: 40µV rms @10Hz to 100kHz Bandwidth
Thermal Protection
Over-Current Protection
Temperature Range: -40°C to +85°C
Packages:
2 Key Features
3 Independent Voltage Regulators with Shutdown
Output Current: 300mA each LDO
Programmable Output Voltage Range: 1.25V to 3.6V in 50mV
- 16-pin QFN 3x3
- 16-pin TQFN 3x3
3 Applications
The AS1355 is ideal for cordless and mobile phones, MP3 players,
CD and DVD players, PDAs, hand-held computers, digital cameras,
and any other hand-held battery-powered device.
Steps
Figure 1. AS1355 - Typical Application Diagram
+5V
VDD1
VOUT1
1µF
3.3V
VDD2
1µF
VDD3
VOUT2
1µF
1.8V
AS1355
VOUT3
1µF
REF
1.5V
VDDA
EN1
C
REF
= 100nF
(Improved Noise Performance)
GND
µP
EN2
EN3
www.ams.com/LDOs/AS1355
Revision 1.3
1 - 12
AMSCO [ AUSTRIAMICROSYSTEMS AG ]
