BDXXFC0WEFJ Datasheet, PDF (10/20 Pages) Rohm – Low saturation with PDMOS output

BDxxFC0WEFJ series
●Thermal Design
◎HTSOP-J8
4.0
⑤3.76W
3.0
④2.11W
2.0
③1.10W
1.0
②0.82W
①0.50W
0
0
25
50
75
100
125
℃ Ambient_周Te_囲m_温p_度e_:r_Ta_atu_[℃re_] : Ta [ ]
Datasheet
Measurement condition: mounted on a ROHM board
× × PCB size: 70mm 70mm 1.6mm
・ ^{(PCB with thermal via)}
Solder the thermal pad to Ground
① IC only
θ ℃ j-a=249.5 /W
② （ × ） 1-layer copper foil : 0mm 0mm
θ ℃ j-a=153.2 /W
③ （ × ） 2-layer copper foil : 15mm 15mm
θ ℃ j-a=113.6 /W
④ （ × ） 2-layer copper foil : 70mm 70mm
θ ℃ j-a=59.2 /W
⑤ （ × ） 4-layer copper foil : 70mm 70mm
θ ℃ j-a=33.3 /W
150
As the power consumption increases above the maximum allowable power dissipation of the chip, the temperature across
the chip also increases. When considering thermal design for the regulator, operation should be maintained within the
following conditions:
℃ 1. Ambient temperature Ta can be not higher than 85 .
℃ 2. Chip junction temperature (Tj) can be not higher than 150 .
Chip junction temperature can be determined as follows:
Calculation based on ambient temperature (Ta)
θ × Tj=Ta+ j-a W
＜ ＞ Reference values
θ ℃ × j-a: HTSOP-J8 153.2 /W 1-layer PCB (copper foil density 0mm 0mm)
℃ × 113.6 /W 2-layer PCB (copper foil density 15mm 15mm)
℃ × 59.2 /W 2-layer PCB (copper foil density 70mm 70mm)
℃ × 33.3 /W 4-layer PCB (copper foil density 70mm 70mm)
× × PCB size: 70mm 70mm 1.6mm (PCB with thermal via)
Most of the heat loss that occurs in the BDxxFC0WEFJ series is generated from the output Pch FET. Power loss is
determined by the voltage drop across VCC-OUT and the output current. Be sure to confirm the system’s input and output
voltages, as well as the output current conditions in relation to the power dissipation characteristics of the VCC and VOUT in
the design. Bearing in mind that the power dissipation may vary substantially depending on the PCB employed, it is
important to consider PCB size based on thermal design and power dissipation characteristics of the chip with the PCB.
× Power consumption [W] = Input voltage (VCC) - Output voltage (VOUT) IOUT (Average)
Example: Where VCC=5.0V, VOUT=3.3V, IOUT (Average) = 0.1A,
× Power consumption [W] = 5.0V - 3.3V 0.1A
=0.17W
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TSZ22111 15 001
10/17
TSZ02201-0R6R0A600480-1-2
2013.08.27 Rev.001