hufa76407dk8 Fairchild Semiconductor, hufa76407dk8 Datasheet - Page 8

• Manufacturer Part Number: hufa76407dk8
• Description: 3.5a, 60v, 0.105 Ohm, Dual N-channel, Logic Level Ultrafet Power Mosfet
• Manufacturer: Fairchild Semiconductor

T
T
The transient thermal impedance (Z
varied top copper board area. Figure 24 shows the effect of
copper pad area on single pulse transient thermal
impedance. Each trace represents a copper pad area in
square inches corresponding to the descending list in the
©2001 Fairchild Semiconductor Corporation
T
J2
J2
J2
= (0.5 Watts)(159
= 150
=
P
2
R
o
C
160
120
80
40
JA
0
10
+
-1
P
COPPER BOARD AREA - DESCENDING ORDER
0.020 in
0.140 in
0.257 in
0.380 in
0.493 in
1
R
o
C/W) + (0 Watts)(97
2
2
2
2
2
+
T
A
FIGURE 24. THERMAL RESISTANCE vs MOUNTING PAD AREA
JA
) is also effected by
10
o
0
C/W) + 70°C
t, RECTANGULAR PULSE DURATION (s)
(EQ. 5)
10
graph. Spice and SABER thermal models are provided for
each of the listed pad areas.
Copper pad area has no perceivable effect on transient
thermal impedance for pulse widths less than 100ms. For
pulse widths less than 100ms the transient thermal
impedance is determined by the die and package. Therefore,
CTHERM1 through CTHERM5 and RTHERM1 through
RTHERM5 remain constant for each of the thermal models. A
listing of the model component values is available in Table 1.
1
10
2
HUFA76407DK8 Rev. B
10
3