Datas heet
AS1335
1 . 5 A , 1 . 5 M H z , S y n c h r o n o u s D C / D C St e p - D o w n C o n v e r t e r
1 General Description
The AS1335 is a high-efficiency, constant-frequency
synchronous buck converter available in a fixed or an
adjustable output voltage version. The wide input volt-
age range (2.6V to 5.25V), the high output current (up to
1.5A) and minimal external component requirements
make the AS1335 perfect for any single Li-Ion battery-
powered application.
Typical supply current with no load is 400µA and
decreases to
≤1µA
in shutdown mode. The highly effi-
cient duty cycle (100%) provides low dropout operation,
prolonging battery life in portable systems.
The device also offers a power-ok signal with a 215ms
delay, which can be reseted or delayed further via the
RSI pin.
An internal synchronous switch increases efficiency and
eliminates the need for an external Schottky diode. The
internally fixed switching frequency (1.5MHz) allows for
the use of small surface mount external components.
The AS1335 is available in a 10-pin TDFN 3x3mm pack-
age.
2 Key Features
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High Efficiency: Up to 96%
Output Current: 1.5A
Input Voltage Range: 2.6V to 5.25V
Output Voltage Range: 0.6V to V
IN
Constant Frequency Operation: 1.5MHz
No Schottky Diode Required
Power OK with 215ms delay
Low Dropout Operation: 100% Duty Cycle
Low Quiescent Supply Current: 400µA
Shutdown Mode Supply Current:
≤1µA
Current Mode Operation for Excellent Line/Load
Transient Response
Thermal Protection
10-pin TDFN 3x3mm Package
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3 Applications
The device is ideal for mobile communication devices,
laptops and PDAs, ultra-low-power systems, threshold
detectors/discriminators, telemetry and remote systems,
medical instruments, or any other space-limited applica-
tion with low power-consumption requirements.
Figure 1. AS1335 - Typical Application Diagram
V
IN
2.6V to 5.25V
C
IN
22µF
VIN
NC
SW
2.2µH
C
OUT
22µF
V
OUT
1.0V, 1.5A
PGND
AS1335
EN
POK
GND
GND
FB
RSI
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