irs20954s International Rectifier Corp., irs20954s Datasheet - Page 11

• Manufacturer Part Number: irs20954s
• Description: Protected Digital Audio Driver
• Manufacturer: International Rectifier Corp.

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Self Reset Protection
By simply putting a capacitor between the CSD and V
Shutdown Input
By externally discharging Ct down to below V
shutdown mode. The operation resumes when the voltage of CSD pin comes back and cross the upper threshold of
CSD, Vth1, by its charging process.
Designing Ct
Timing capacitor Ct programs the protection resume interval timing t
or
For example, t
shutdown release, is given as:
or
Protection-resume timing t
the repetitive sequences of shutdown and resume when the load is in continuous short circuit. In most of
applications, the minimum recommended protection-resume timing t
t
Ct
t
Ct
SU
PR
1
t
t
1
0
. 0
SU
PR
˜ 1 .
1 .
7 .
where I
˜ 7
˜
˜
˜
˜
V
Ct
I
V
I
Ct
CSD
CSD
DD
DD
I
PR
I
˜
CSD
˜
CSD
V
V
CSD
V
is 1.2 s with a 10 µF capacitor for V
DD
DD
DD
[F]
[F]
Figure 8: Self-Reset Protection Configuration
is charge/discharge current in CSD pin, 100 µA.
is supply voltage respect to V
[sec]
[sec]
PR
should be long enough to avoid over heating and failure of the MOSFET from
th2
, for example with a transistor shown in Fig. 9, the IRS20954 enters
Ct
SS
, the OCP in the IRS20954 acts as a self.
VDD
CSD
VSS
VREF
OCSET
NC
DT
IN
SS.
DD
=10.8 V. The start-up time t
CSH
VCC
COM
HO
VB
VS
NC
LO
PR
PR
given as:
is 0.1 s.
SU
, from power-up to
IRS20954S
11