数据搜索系统,热门电子元器件搜索 |
|
ADM1029ARQ 数据表(PDF) 10 Page - Analog Devices |
|
ADM1029ARQ 数据表(HTML) 10 Page - Analog Devices |
10 / 48 page REV. 0 ADM1029 –10– D+ D– REMOTE SENSING TRANSISTOR LOW-PASS FILTER fC = 65kHz VDD TO ADC VOUT+ VOUT– I N I IBIAS BIAS DIODE Figure 5. Signal Conditioning for Remote Diode Temperature Sensors TEMPERATURE LIMITS The contents of the Local and Remote Temperature Value Regis- ters (addresses A0h to A2h) are compared to the contents of the High and Low Limit Registers at addresses 90h to 92h and 98h to 9Ah. How the ADM1029 responds to overtemperature/ undertemperature conditions depends on the status of the Tem- perature Fault Action Registers (addresses 40h to 42h). The response of CFAULT, INT, and fan-speed-to-temperature events depends on the setting of these registers, as explained later. Table II. Temperature Data Format Temperature Digital Output –128 °C 1000 0000 –125 °C 1000 0011 –100 °C 1001 1100 –75 °C 1011 0101 –50 °C 1100 1110 –25 °C 1110 0111 0 °C 0000 0000 +10 °C 0000 1010 +25 °C 0001 1001 +50 °C 0011 0010 +75 °C 0100 1011 +100 °C 0110 0100 +125 °C 0111 1101 +127 °C 0111 1111 To prevent ground noise interfering with the measurement, the more negative terminal of the sensor is not referenced to ground, but biased above ground by an internal diode at the D– input. If the sensor is used in a noisy environment, a capacitor of value up to 1000 pF may be placed between the D+/D– pins. To measure ∆V BE, the sensor is switched between operating currents of I and N × I. The resulting waveform is passed through a 65 kHz low-pass filter to remove noise, and to a chopper-stabilized amplifier that performs the functions of amplification and rectification of the waveform to produce a dc voltage proportional to ∆V BE. This voltage is measured by the ADC to give a temperature output in 8-bit two’s complement format. To further reduce the effects of noise, digital filtering is performed by averaging the results of 16 measurement cycles. An external temperature measurement takes nominally 9.6 ms. The results of external temperature measurements are stored in 8-bit, two’s complement format, as illustrated in Table II. OFFSET REGISTERS Digital noise and other error sources can cause offset errors in the temperature measurement, particularly on the remote sen- sors. The ADM1029 offers a way to minimize these effects. The offsets on the three temperature channels can be measured during system characterization and stored as two’s complement values in three offset registers at addresses 30h to 32h. The offset values are automatically added to, or subtracted from, the tem- perature values, depending on whether the two’s complement number corresponds to a positive or negative offset. Offset val- ues from –15 °C to +15°C are allowed. The default value in the offset registers is zero, so if no offsets are programmed, the temperature measurements are unaltered. |
类似零件编号 - ADM1029ARQ |
|
类似说明 - ADM1029ARQ |
|
|
链接网址 |
隐私政策 |
ALLDATASHEETCN.COM |
ALLDATASHEET是否为您带来帮助? [ DONATE ] |
关于 Alldatasheet | 广告服务 | 联系我们 | 隐私政策 | 链接交换 | 制造商名单 All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |