MAX17843 datasheet(31/131 Pages) MAXIM

31 / 131 page

Die Temperature Measurement

The die temperature measurement allows the host to

compute the device temperature (TDIE) as it relates to

the acquisition accuracy, and allows the device to auto-

matically shut itself down when TDIE > 145°C. The mea-

surement employs a source whose voltage (VPTAT) is

proportional to absolute temperature (PTAT), as shown in

Figure 10. The VPTAT measurement is enabled by setting

DIAGSEL[2:0] to 0b110 and the 14-bit measurement is

stored in DIAG[15:2]. The die temperature measurement

requires a settling time of 50µs from the start of the mea-

surement cycle until the diagnostic conversion. As long as

two or more cell measurements are enabled, there will be

sufficient settling time for this measurement. See Figure 17

and Table 10 for a detailed view of this timing.

The PTAT voltage is computed as follows:

VPTAT = (DIAG[15:2]/16384d) x VREF

where VREF = 2.307V. The measured voltage can be

converted into °C as follows:

TDIE (in °C) = (VPTAT/AV_PTAT) + TOS_PTAT - 273°C

See the Electrical Characteristics table for AV_PTAT and

TOS_PTAT values.

Die Temperature Alert

The ALRTTEMP bit is updated at the end of each mea-

surement cycle for which DIAGSEL[2:0] = 0b110. If

ALRTTEMP is set, it signifies that TDIE > TALRTTEMP, or

that the diagnostic measurement did not have sufficient

settling time (< 50μs) and therefore can not be accurate. If

ALRTTEMP is set, the host should consider the possibility

that the acquisition does not meet the expected accuracy

specification, or that the die temperature measurement

itself may be inaccurate due to insufficient settling time

(< 2 cell measurements enabled).

Figure 10. Die Temperature Measurement

MUX

ADC

VREF

VTHRM

AGND

VPTAT

ALRTEMP

1.230V

MAX17843

12-Channel, High-Voltage Smart Sensor

Data-Acquisition Interface

www.maximintegrated.com

Maxim Integrated │ 31

MAX17843 датащи(PDF) 31 Page - Maxim Integrated Products

MAX17843 датащи(HTML) 31 Page - Maxim Integrated Products

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL