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Output Voltage with temperature (5mA Load)
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1.38
1.36
1.34
1.32
1.30
1.28
1.26
1.24
1.22
TJUNC = TAMB + PD ∗ (θJC) + PD ∗ (θCA
= TAMB + PD ∗ (θJA
)
)
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LQFKHVꢀ RIꢀ FRSSHUꢀ DOORFDWHGꢀ IRUꢀ ³KHDWꢀ VSUHDGLQJ´ꢌꢀ WKH
UHVXOWLQJꢀθJAꢀLVꢀDERXWꢀꢑ0°C/Wꢂꢀ
-50
0
50
100
150
Temperature [oC]
Output Voltage with temperature (500mA Load)
1.35
1.34
1.33
1.32
1.31
1.30
1.29
1.28
1.27
1.26
1.25
Based on a power dissipation of .8W (Load x Vin-Vout =
.4A x [3.3V-1.3V]) with an ambient of 70°C, the result-
ing junction temperature will be:
TJUNC = TAMB + PD ∗ (θJA
)
= 70°C + .8W ∗ (70°C/W)
= 70°C + 55°C = 125°C
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-50
-25
0
25
50
75
Temperature [oC]
Measurements showing performance up to a junction
temperature of 125°C are presented in )LJXUH ꢁꢂꢀThey
were performed under light load conditions (5mA); this
allows the ambient temperature to be representative of
the internal junction temperature.
Ground Current with Temperature (No Load)
700
600
500
400
300
200
100
0
Note: The use of multi-layer board construction with
separate ground and power planes will further enhance
the overall thermal performance. In the event of no cop-
per area being dedicated for heat spreading, a multi-
layer board construction using only the minimum size
pad layout will typically provide the CM3001 with an
overall θJA of 70°C/W, which allows up to 0.8W to be
dissipated safely.
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VSHFLILFꢀDSSOLFDWLRQꢂ
-50
0
50
100
150
Temperature [oC]
)LJXUHꢃꢂꢆꢃꢃꢀꢁꢂꢃꢃꢄ
!071472,3.0ꢅ;8ꢆꢅ%02507,9:70
2002 California Micro Devices Corp. All rights reserved.
6
215 Topaz Street, Milpitas, California 95035
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Tel: (408) 263-3214
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Fax: (408) 263-7846
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www.calmicro.com 01/24/02