Data Sheet

LTM4640

analog.com

Rev. 0

29 of 38

Figure 35 shows a thermal capture of LTM4640 with 12V input, 1V output at 20A, 600kHz, 21°C ambient

temperature, without airflow and heat sink conditions.

Figure 35. Thermal Image at 12VIN, 1VOUT at 20A, 600kHz, 21°C Ambient Temperature, without Airflow and Heat Sinking

Table 9. 1V Output

DERATING CURVE

VIN (V)

POWER LOSS

CURVE

AIRFLOW

(LFM)

HEAT SINK

θJA (°C/W)

Figure 29, Figure 30

5, 12

Figure 26

0

None

14

Figure 29, Figure 30

5, 12

Figure 26

200

None

11

Figure 29, Figure 30

5, 12

Figure 26

400

None

10

Table 10. 1.5V Output

DERATING CURVE

VIN (V)

POWER LOSS

CURVE

AIRFLOW

(LFM)

HEAT SINK

θJA (°C/W)

Figure 31, Figure 32

5, 12

Figure 27

0

None

14

Figure 31, Figure 32

5, 12

Figure 27

200

None

11

Figure 31, Figure 32

5, 12

Figure 27

400

None

10

Table 11. 3.3V Output

DERATING CURVE

VIN

(V)

POWER LOSS

CURVE

AIRFLOW

(LFM)

HEAT SINK

θJA (°C/W)

Figure 33, Figure 34

5, 12

Figure 28

0

None

15

Figure 33, Figure 34

5, 12

Figure 28

200

None

12

Figure 33, Figure 34

5, 12

Figure 28

400

None

11