ML7406 datasheet(83/104 Pages) ETC2

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FEDL7406-02

ML7406

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○Temperature measurement function

ML7406 has temperature measurement function. This temperature information can be from A_MON pin (pin#23) as analog

output or digital information using[TEMP: B1 0x09] register. Analog or digital can be switched by [MON_CTRL: B0 0x4D]

(Note)

Please do not set TEMP_OUT( [MON_CTRL: B0 0x4D(4)]) and TEMP_ADC_OUT( [MON_CTRL: B0 0x4D(5)]) at the

same time. Correct value reading may not be guaranteed.

[Analog output]

ML7406 has current source circuits and its current flow through 75kΩ connected to A_MONpin (pin#23). From voltage

information, temperature information can be obtained.

Current from current source circuits are 10μA at 25˚C. The following formula can be used to calculate temperature from the

current.

Itemp = (273+ Temp) / (273+25) * 10 (μA)

Therefore, if 75kΩ resister is connected, temperature can be calculated using the following formula.

Vamon = (273+ Temp) / (275+25) * 10E-6 * 75000

If temperature is -40˚C to 85˚C, Vamon will be 0.59V to 0.9V.

The following formula can be used to calculate temperature from voltage .

Temp = Vamon * 397.3 - 273

[Digital output]

Digital temperature information is using 6 bit ADC to convert from the above analog information. Internally, 4samples

information are added and indicates as 8bit information in [TEMP: B1 0x09] register. Ignoring low 2 bits, upper 6bitare used

for average temperature information.

Temperature information is updated every 16μs([ADC_CLK_SET: B1 0x08] register. If 1.73MHzis selected, it is updated

every 18.5μs.

ML7406 Datasheet(PDF) 83 Page - List of Unclassifed Manufacturers