鈻?/div>
Description
The A5973AD is a step down monolithic power
switching regulator with a minimum switch current
limit of 1.8 A so it is able to deliver more than
1.5 A DC current to the load depending on the
application conditions. The output voltage can be
set from 1.235 V to 35 V. The high current level is
also achieved thanks to an HSOP8 package with
exposed frame, that allows to reduce the R
th(JA)
down to approximately 40 擄C/W. The device uses
an internal P-channel D-MOS transistor (with a
typical R
DS(on)
of 250 m鈩? as switching element
to minimize the size of the external components.
An internal oscillator fixes the switching frequency
at 500 kHz. Having a minimum input voltage of
4 V only, it is particularly suitable for 5 V bus.
Pulse by pulse current limit with the internal
frequency modulation offers an effective constant
current short circuit protection. Pulse by pulse
current limit with the internal frequency
modulation offers an effective constant current
short circuit protection.
L1 15uH
Applications
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Dedicated to automotive applications
Figure 1.
Typical application
VCC
COMP
C4
VIN=4V to 35V
8
4
1
2
OUT
SYNCH
Vout=3.3V
A5973AD
FB
6
5
7
GND
INH
3
D1
STPS340U
R1
5k6
C2
330uF
6.3V
R2
3k3
C1
10uF
35V
CERAMIC
C3
220pF
22nF
R3
4k7
VREF
3.3V
May 2008
Rev 4
1/17
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