MIC4425BM TR Micrel Inc, MIC4425BM TR Datasheet - Page 10

• Manufacturer Part Number: MIC4425BM TR
• Description: IC DRIVER MOSFET 3A DUAL 8-SOIC
• Manufacturer: Micrel Inc

Specifications of MIC4425BM TR

• Configuration: Low-Side
• Input Type: Inverting and Non-Inverting
• Delay Time: 33ns
• Current - Peak: 3A
• Number Of Configurations: 2
• Number Of Outputs: 2
• Voltage - Supply: 4.5 V ~ 18 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• High Side Voltage - Max (bootstrap): -
• Other names: MIC4425BMTR; MIC4425BMTR

MIC4423/4424/4425
Then quiescent power loss:
Total power dissipation, then, is:
Assuming an SOIC package, with an θ
result in the junction running at:
above ambient, which, given a maximum ambient tempera-
ture of 60°C, will result in a maximum junction temperature
of 89.4°C.
EXAMPLE 2: A MIC4424 operating on a 15V input, with one
driver driving a 50Ω resistive load at 1MHz, with a duty cycle
of 67%, and the other driver quiescent, in a maximum ambi-
ent temperature of 40°C:
First, I
Given R
and:
(because only one side is operating)
and:
(this assumes that the unused side of the driver has its input
grounded, which is more efficient)
MIC4423/4424/4425
O
must be determined.
0.2454 x 120 = 29.4°C
P
I
I
= (1,000,000 x 15 x 3.3 x 10
= 0.025 W
P
= 0.015W
P
P
O
I
P
P
O
O
O
Q
L
Q
D
from the characteristic curves then,
T
L
= V
= 15 / (3.3 + 50)
= 0.281A
= I
= 15 x [(0.67 x 0.00125) + (0.33 x 0.000125) +
= V
= 12 x [(0.5 x 0.0035) + (0.5 x 0.0003)]
= 0.0228W
= 0.2160 + 0.0066 + 0.0228
= 0.2454W
= (0.281)
= 0.174W
= F x V
2
S
(1 x 0.000125)]
x R
/ (R
S
x [D x I
O
O
x D
S
+ R
x (A•s)/2
2
x 3.3 x 0.67
LOAD
H
+ (1 – D) x I
)
–9
) / 2
JA
L
]
of 120°C/W, this will
10
then:
In a ceramic package with an θ
power results in a junction temperature given the maximum
40°C ambient of:
The actual junction temperature will be lower than calculated
both because duty cycle is less than 100% and because the
graph lists R
will be somewhat lower.
Definitions
P
P
C
P
P
R
V
D = Duty Cycle expressed as the fraction of time the input
I
I
I
H
D
D
Q
L
L
L
T
f = Operating Frequency of the driver in Hertz
O
S
= Output resistance of a driver in Ohms.
= Load Capacitance in Farads.
= Power supply current drawn by a driver when both
= Power supply current drawn by a driver when both
= Output current from a driver in Amps.
= Total power dissipated in a driver in Watts.
= Power dissipated in the driver due to the driver’s
= Power dissipated in a quiescent driver in Watts.
= Power dissipated in a driver when the output
= Power supply voltage to the IC in Volts.
(0.213 x 100) + 40 = 61.4°C
to the driver is high.
inputs are high and neither output is loaded.
load in Watts.
changes states (“shoot-through current”) in Watts.
NOTE: The “shoot-through” current from a dual
transition (once up, once down) for both drivers is
stated in the graph on the following page in ampere-
nanoseconds. This figure must be multiplied by the
number of repetitions per second (frequency to find
Watts).
P
inputs are low and neither output is loaded.
D
= 0.174 + 0.025 + 0.0150
= 0.213W
DS(on)
at a T
J
of 125°C and the R
JA
of 100°C/W, this amount of
DS(on)
Micrel, Inc.
at 61°C T
July 2005
J