NCV8772
http://onsemi.com
14
RESET DELAY AND RESET THRESHOLD OPTIONS
(D2PAK−7)
DT = GND
Reset
Time
DT = V
out
Reset
Time
Reset
Threshold
NCV87721D7S 8 ms 128 ms 93%
NCV87722D7S 8 ms 32 ms 93%
NCV87723D7S 16 ms 64 ms 93%
NCV87724D7S 32 ms 128 ms 93%
NCV87725D7S 4 ms 8 ms 93%
NCV8772AD7S 8 ms 128 ms 90%
NCV8772BD7S 8 ms 32 ms 90%
NCV8772CD7S 16 ms 64 ms 90%
NCV8772DD7S 32 ms 128 ms 90%
NCV8772ED7S 4 ms 8 ms 90%
NOTE: The timing values can be selected from the following list:
4, 8, 16, 32, 64, 128 ms. Contact factory for options not
included in ORDERING INFORMATION table on page 14.
Thermal Considerations
As power in the NCV8772 increases, it might become
necessary to provide some thermal relief. The maximum
power dissipation supported by the device is dependent
upon board design and layout. Mounting pad configuration
on the PCB, the board material, and the ambient temperature
affect the rate of junction temperature rise for the part. When
the NCV8772 has good thermal conductivity through the
PCB, the junction temperature will be relatively low with
high power applications. The maximum dissipation the
NCV8772 can handle is given by:
P
D
(
max
)
+
ƪ
T
J(max)
* T
A
ƫ
R
qJA
(eq. 1)
Since T
J
is not recommended to exceed 150°C, then the
NCV8772 soldered on 645 mm
2
, 1 oz copper area, FR4 can
dissipate up to 2.35 W (for D2PAK−5) when the ambient
temperature (T
A
) is 25°C. See Figure 34 for R
q
JA
versus
PCB area. The power dissipated by the NCV8772 can be
calculated from the following equations:
P
D
+ V
in
ǒ
I
q
@I
out
Ǔ
) I
out
ǒ
V
in
* V
out
Ǔ
(eq. 2)
or
V
in(max)
+
P
D(max)
)
ǒ
V
out
I
out
Ǔ
I
out
) I
q
(eq. 3)
NOTE: Items containing I
q
can be neglected if I
out
>> I
q
.
Figure 34. Thermal Resistance vs. PCB Copper Area
(D2PAK−5)
40
50
60
70
80
90
100
0 100 200 300 400 500 600 700
COPPER HEAT SPREADER (mm
2
)
R
q
JA
, THERMAL RESISTANCE (°C/W)
PCB 1 oz Cu
PCB 2 oz Cu
Hints
V
in
and GND printed circuit board traces should be as
wide as possible. When the impedance of these traces is
high, there is a chance to pick up noise or cause the regulator
to malfunction. Place external components, especially the
output capacitor, as close as possible to the NCV8772 and
make traces as short as possible.
ORDERING INFORMATION
Device Output Voltage
Reset Delay Time
(DT = GND/V
out
for D2PAK−7)
Reset Threshold Marking Package Shipping
†
NCV87722DT50RKG 5.0 V 16 ms 93% 772250G DPAK−5
(Pb−Free)
2500 /
Tape & Reel
NCV87721D5S50R4G 5.0 V 8 ms 93% NC
V8772150
D2PAK−5
(Pb−Free)
800 /
Tape & Reel
NCV87725D7S50R4G 5.0 V 4/8 ms 93% NC
V8772550
D2PAK−7
(Pb−Free)
750 /
Tape & Reel
NCV87722DT33RKG 3.3 V 16 ms 93% 772233G DPAK−5
(Pb−Free)
2500 /
Tape & Reel
NCV87722D5S33R4G 3.3 V 16 ms 93% NC
V8772233
D2PAK−5
(Pb−Free)
800 /
Tape & Reel
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D.
(56 pages)
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