A S 134 6- 4 9
Du al St ep- Down C on ver t e r w ith B att ery Mon ito r i ng
1 General Description
The AS1346, AS1347, AS1348, AS1349 family is a high-efficiency,
constant-frequency dual buck converter available with fixed voltage
versions. The device provides two independent DC/DC Converters
with output currents between 0.5A and 1.2A. The wide input voltage
range (2.7V to 5.5V), automatic powersave mode and minimal
external component requirements make the AS134x family perfect
for SSD and many other battery-powered applications.
In shutdown mode the typical supply current decreases to
≤1μA.
The highly efficient duty cycle (100%) provides low dropout
operation, prolonging battery life in portable systems.
An internal synchronous switching scheme increases efficiency and
eliminates the need for an external Schottky diode. The fixed
switching frequency (2.0MHz) allows the use of small surface mount
inductors.
The integrated monitoring function can be configured that either the
output voltage (Power Okay function ) or the input voltage (Battery
Monitoring Function) can be supervised.
Table 1. Available Products
Devices
AS1346
AS1347
AS1348
AS1349
I
OUT1
1.2A
0.5A
0.5A
1.2A
I
OUT2
0.5A
0.5A
0.95A
1.2A
2 Key Features
High Efficiency: Up to 95%
Output Current:
Input Voltage Range: 2.7V to 5.5V
Output Voltage Range: 1.2V to 3.6V (available in 100mV steps)
Constant Frequency Operation: 2.0MHz
180º Out of Phase Operation
Low Battery Detection
Low Dropout Operation: 100% Duty Cycle
Shutdown Mode Supply Current:
1μA
No Schottky Diode Required
Output Disconnect in Shutdown
Non standard variants available within two weeks
12-Pin TDFN 3x3mm Package
3 Applications
The device is ideal for SSD applications, mobile communication
devices, laptops and PDAs, ultra-low-power systems, threshold
detectors/discriminators, telemetry and remote systems, medical
instruments, or any other space-limited application with low power-
consumption requirements.
The AS1346-49 is available in a 12-Pin TDFN 3x3mm package.
Figure 1. AS1346 - Typical Application Diagram with POK Function
V
IN
2.7V to 5.5V
L1 = 3.3μH
C
IN
PVIN
PVIN
VDD
EN1
EN2
LBI
PGND
SW1
V
OUT1
3.3V 1200mA
C
OUT1
L2 = 3.3μH
C
OUT2
AS1346
FB1
SW2
FB2
LBO
AGND
V
OUT2
1.8V 500mA
POK Function
Revision 1.10
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AMSCO [ AUSTRIAMICROSYSTEMS AG ]
