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Datasheet
AS1326
High Current, 0.8A DC-DC Step-Up Converters
1 General Description 2 Key Features
! Up to 800mA Output
The AS1326A/AS1326B are high-efficiency, high cur-
rent, DC-DC step-up converters specifically designed for
! Constant-Frequency (1MHz) Operation
battery-powered wireless applications. Low quiescent
supply current (65A), high operating frequency (1MHz),
! Up to 96% Efficiency
and minimal external component requirements make
these devices perfect for small hand-held applications.
! Input Range: 0.7 to 5.0V
Table 1. Standard Products
! Fixed Output: 3.3V
Model Input Signal Activation
! Adjustable Output: 2.5 to 5.0V
AS1326A Logic-Low On
! PWM Synchronous-Rectified Technology
AS1326B Logic-High On
! Logic-Controlled Shutdown: 0.1A
Both devices use synchronous-rectified pulse-width
modulation (PWM) boost technology to generate 2.5 to
! Synchronizable Switching Frequency
5.0V outputs from a wide range of inputs, such as 1 to 3
(0.5 to 1.2MHz)
alkaline/NiCd/NiMH cells or a single lithium-ion (Li+)
cell. Automatic powersave operation significantly
! Adjustable Current Limit
improves efficiency at light-loads.
! Adjustable Soft-Start
Continuous switching mode is available for applications
requiring constant-frequency operation at all load cur-
! 10-pin TDFN (3.0mm x 3.0mm) Package
rents. PWM operation can also be synchronized to an
external clock to protect sensitive frequency bands in
3 Applications
communications equipment.
Analog soft-start and adjustable current limit permit opti-
The devices are ideal for digital cordless phones. mobile
mization of rush in current and external component size.
phones, wireless handsets, hand-held instruments,
PDAs, two-way pagers, and any battery-operated equip-
The AS1326A/AS1326B are available in a 10-pin TDFN
ment.
(3.0mm x 3.0mm) package.
Figure 1. AS1326 - Block Diagram
5 Undervoltage
AS1326
+
Lockout
OUT
IC Power
9
2.15V
On Q
10 D POUT
AS1326B
Startup
only
ON
Controller
Osc
10
AS1326A
8
only
ONN On Rdy
En
LX
Reference
2
1.25V En Osc Osc
Ref GND
1MHz Osc
REF
7
CLK/SEL Mode Mode
3
PGND
GND
6
FB ISET
CLK/SEL
4
FB
1
ISET
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Technical content still valid