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BDxxFC0 series

Datasheet

Datasheet

TSZ02201-0G2G0A600040-1-2

© 2016 ROHM Co., Ltd. All rights reserved.

16.May.2016 Rev.004

www.rohm.com

TSZ22111・15・001

●Thermal Design

■

HTSOP-J8

Figure 74.

■

TO252-3/5

Figure 75.

IC mounted on ROHM standard board based on JEDEC.

Board material: FR4

Board size

1s

114.3 mm x 76.2 mm x 1.57 mmt

2s2p

114.3 mm x 76.2 mm x 1.6 mmt

Mount condition: PCB and exposed pad are soldered.

Top copper foil: The footprint ROHM recommend.

+ wiring to measure.

①: 1-layer PCB (Copper foil area on the reverse side of

PCB: 0 mm x 0 mm)

②: 4-layer PCB (2 inner layers and copper foil area on the

reverse side of PCB: 74.2mm x 74.2 mm)

Condition

Condition

IC mounted on ROHM standard board based on JEDEC.

Board material: FR4

Board size

1s

114.3 mm x 76.2 mm x 1.57 mmt

2s2p

114.3 mm x 76.2 mm x 1.6 mmt

Mount condition: PCB and exposed pad are soldered.

Top copper foil: The footprint ROHM recommend.

+ wiring to measure.

①: 1-layer PCB (Copper foil area on the reverse side of

PCB: 0 mm x 0 mm)

②: 4-layer PCB (2 inner layers and copper foil area on the

reverse side of PCB: 74.2mm x 74.2 mm)

Condition

Condition

When operating at temperature more than Ta=25°C, please refer to the power dissipation characteristic curve shown in Figure

74 and 75.

The IC characteristics are closely related to the temperature at which the IC is used, so it is necessary to operate the IC at

temperatures less than the maximum junction temperature Tjmax.

Figure 74 and 75 show the acceptable power dissipation characteristic curves of the HTSOP-J8 and TO252-3/5 packages. Even

when the ambient temperature (Ta) is at normal temperature (25°C), the chip junction temperature (Tj) may be quite high so

please operate the IC at temperatures less than the acceptable power dissipation.

The calculation method for power consumption Pc(W) is as follows

Pc=(Vcc－Vo)×Io+Vcc×Icc

Acceptable loss Pd ≥ Pc

Solving this for load current Io in order to operate within the acceptable loss

It is then possible to find the maximum load current Iomax with respect to the applied voltage Vcc at the time of thermal design.

Calculation Example) When TO252-3 / TO252-5, Ta=85°C, Vcc=13.5V, Vo=5.0V

Io ≤

Pd－Vcc×Icc

Vcc－Vo

Vcc

: Input voltage

Vo

: Output voltage

Io

: Load current

Icc

: Circuit current

Io ≤ 365.6mA (Icc : 0.5mA)

Io ≤

3.115－13.5×Icc

8.5

Figure 75

②θja=20.8 °C/W → -48.1mW/°C

25°C = 6W → 85°C =3.115W

②

2.8 W

①

0.6W

0

0.5

1

1.5

2

2.5

3

3.5

0

255075

100

125

150

Ambient Temperature: Ta[°C]

②

6W

①

1.1 W

0

2

4

6

8

0

255075

100

125

150

Ambient Temperature: Ta [°C]