IRS20954SPBF International Rectifier, IRS20954SPBF Datasheet - Page 21

• Manufacturer Part Number: IRS20954SPBF
• Description: IC AMP DGTL AUDIO PROT 16-SOIC
• Manufacturer: International Rectifier
• Type: MOSFET Driverr

Specifications of IRS20954SPBF

• Applications: Amplifiers, Receivers
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Junction Temperature Estimation
The power dissipation in the IRS20954 consists of following dominant items;
www.irf.com
-
-
-
1.
The dissipation in floating input section is given by;
2.
The dissipation in low-side includes loss from logic circuitry and loss from driving LO, and is given by;
3.
The dissipation in high-side includes loss from logic circuitry and loss from driving LO and is given by;
=
P
≈
P
MID
LOW
V
(
I
+
QCC
P
P
P
P
Where
P
P
V
R
For obtaining a value of R
P
Where
P
P
R
R
R
Qg is total gate charge of low-side MOSFET.
P
BUS
=
=
MID
LOW
HIGH
MID
ZDD
LDD
+BUS
LOW
LDD
LO
HIGH
R
DD
O
g(int)
g
P
⋅
P
is external gate resistance.
DD
is equivalent output impedance of LO, typically 10 Ω for the IRS20954.
−
V
ZDD
: dissipation in floating input logic and protection
: Dissipation in Floating Input Section
LDD
is dissipation from gate drive stage to LO.
is a resistor feeding V
: dissipation in low-side
CC
is dissipation from internal logic circuitry.
: Dissipation in Low-side
is dissipation from internal logic circuitry.
: dissipation in high-side
V
is dissipation from internal zener diode clamping V
: Dissipation in High-side
is internal gate resistance of MOSFET.
is positive bus voltage feeding V
DD
)
+
+
+
P
⋅
P
⎛
⎜
⎜
⎝
V
LDD
LO
Vcc
DD
⋅
Q
g
⋅
f
SW
Not recommended for new designs.
⋅
R
DD
DD
O
Please use IRS20957SPBF.
, refer to Supplying V
+
from V
R
R
g
O
+
R
Figure 21: Negative V
+BUS
g
(int)
DD
.
⎞
⎟
⎟
⎠
from.
DD
section above.
DD
SS
voltage.
Clamping
IRS20954SPBF
21