參數(shù)資料
型號: MAX6659MEE
廠商: MAXIM INTEGRATED PRODUCTS INC
元件分類: 溫度/濕度傳感器
英文描述: 【1∑C, SMBus-Compatible Remote/Local Temperature Sensors with Overtemperature Alarms
中文描述: DIGITAL TEMP SENSOR-SERIAL, 11BIT(s), 1Cel, RECTANGULAR, SURFACE MOUNT
封裝: 0.150 INCH, 0.025 INCH PITCH, MO-137AB, QSOP-16
文件頁數(shù): 8/17頁
文件大?。?/td> 275K
代理商: MAX6659MEE
M
surements. The noise can be reduced with careful PC
board layout and proper external noise filtering.
High-frequency EMI is best filtered at DXP and DXN
with an external 2200pF capacitor. Larger capacitor
values can be used for added filtering, but do not
exceed 3300pF because it can introduce errors due to
the rise time of the switched current source.
PC Board Layout
Follow these guidelines to reduce the measurement
error of the temperature sensors:
1) Place the MAX6657/MAX6658/MAX6659 as close
as is practical to the remote diode. In noisy environ-
ments, such as a computer motherboard, this dis-
tance can be 4in to 8in (typ). This length can be
increased if the worst noise sources are avoided.
Noise sources include CRTs, clock generators,
memory buses, and ISA/PCI buses.
2) Do not route the DXP-DXN lines next to the deflec-
tion coils of a CRT. Also, do not route the traces
across fast digital signals, which can easily intro-
duce +30
°
C error, even with good filtering.
3) Route the DXP and DXN traces in parallel and in
close proximity to each other, away from any higher
voltage traces, such as +12VDC. Leakage currents
from PC board contamination must be dealt with
carefully since a 20M
leakage path from DXP to
ground causes about +1
°
C error. If high-voltage
traces are unavoidable, connect guard traces to GND
on either side of the DXP-DXN traces (Figure 1).
4) Route through as few vias and crossunders as pos-
sible to minimize copper/solder thermocouple
effects.
5) When introducing a thermocouple, make sure that
both the DXP and the DXN paths have matching
thermocouples. A copper-solder thermocouple
exhibits 3μV/
°
C, and it takes about 200μV of voltage
error at DXP-DXN to cause a +1
°
C measurement
error. Adding a few thermocouples causes a negli-
gible error.
6) Use wide traces. Narrow traces are more inductive
and tend to pick up radiated noise. The 10mil widths
and spacings that are recommended in Figure 1 are
not absolutely necessary, as they offer only a minor
improvement in leakage and noise over narrow
traces. Use wider traces when practical.
7) Add a 200
resistor in series with V
CC
for best
noise filtering (see
Typical Operating Circuit
).
Twisted-Pair and Shielded Cables
Use a twisted-pair cable to connect the remote sensor
for remote-sensor distances longer than 8in or in very
noisy environments. Twisted-pair cable lengths can be
between 6ft and 12ft before noise introduces excessive
errors. For longer distances, the best solution is a
shielded twisted pair like that used for audio micro-
phones. For example, Belden #8451 works well for dis-
tances up to 100ft in a noisy environment. At the
device, connect the twisted pair to DXP and DXN and
the shield to GND. Leave the shield unconnected at the
remote sensor.
For very long cable runs, the cable
s parasitic capaci-
tance often provides noise filtering, so the 2200pF
capacitor can often be removed or reduced in value.
Cable resistance also affects remote-sensor accuracy.
For every 1
of series resistance, the error is approxi-
mately +1/2
°
C.
Low-Power Standby Mode
Standby mode reduces the supply current to less than
10μA by disabling the ADC. Enter hardware standby
(MAX6659 only) by forcing the
STBY
pin low, or enter
software standby by setting the RUN/STOP bit to 1 in
the Configuration Byte register. Hardware and software
standbys are very similar
all data is retained in memo-
ry, and the SMB interface is alive and listening for
SMBus commands. The only difference is that in soft-
ware standby mode, the one-shot command initiates a
conversion. With hardware standby, the one-shot com-
mand is ignored. Activity on the SMBus causes the
device to draw extra supply current.
Driving the
STBY
pin low overrides any software con-
version command. If a hardware or software standby
command is received while a conversion is in progress,
the conversion cycle is interrupted, and the tempera-
8
_______________________________________________________________________________________
MINIMUM
10MILS
10MILS
10MILS
10MILS
GND
DXN
DXP
GND
Figure 1. Recommended DXP-DXN PC Traces
±1°C, SMBus-Compatible Remote/Local Temperature
Sensors with Overtemperature Alarms
相關(guān)PDF資料
PDF描述
MAX6670AUB40 Remote Temperature Switches with Integrated Fan Controller/Driver
MAX6670 Remote Temperature Switches with Integrated Fan Controller/Driver
MAX6668AUA40 Remote Temperature Switches with Integrated Fan Controller/Driver
MAX6668AUA45 Remote Temperature Switches with Integrated Fan Controller/Driver
MAX6668AUA70 Remote Temperature Switches with Integrated Fan Controller/Driver
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MAX6659MEE+ 功能描述:板上安裝溫度傳感器 Remote/Local Temperature Sensor RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準(zhǔn)確性:+/- 1.5 C, +/- 3 C 溫度閾值: 數(shù)字輸出 - 總線接口:2-Wire, I2C, SMBus 電源電壓-最大:5.5 V 電源電壓-最小:4.5 V 最大工作溫度:+ 50 C 最小工作溫度:0 C 關(guān)閉: 安裝風(fēng)格: 封裝 / 箱體: 設(shè)備功能:Temperature and Humidity Sensor
MAX6659MEE+T 功能描述:板上安裝溫度傳感器 Remote/Local Temperature Sensor RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準(zhǔn)確性:+/- 1.5 C, +/- 3 C 溫度閾值: 數(shù)字輸出 - 總線接口:2-Wire, I2C, SMBus 電源電壓-最大:5.5 V 電源電壓-最小:4.5 V 最大工作溫度:+ 50 C 最小工作溫度:0 C 關(guān)閉: 安裝風(fēng)格: 封裝 / 箱體: 設(shè)備功能:Temperature and Humidity Sensor
MAX6659MEE-T 功能描述:板上安裝溫度傳感器 RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準(zhǔn)確性:+/- 1.5 C, +/- 3 C 溫度閾值: 數(shù)字輸出 - 總線接口:2-Wire, I2C, SMBus 電源電壓-最大:5.5 V 電源電壓-最小:4.5 V 最大工作溫度:+ 50 C 最小工作溫度:0 C 關(guān)閉: 安裝風(fēng)格: 封裝 / 箱體: 設(shè)備功能:Temperature and Humidity Sensor
MAX665C/D 功能描述:電荷泵 DICE SALES DICE RoHS:否 制造商:Maxim Integrated 功能:Inverting, Step Up 輸出電壓:- 1.5 V to - 5.5 V, 3 V to 11 V 輸出電流:100 mA 電源電流:1 mA 最大工作溫度:+ 70 C 封裝 / 箱體:SOIC-8 Narrow 封裝:Tube
MAX665C/D+ 功能描述:電荷泵 RoHS:否 制造商:Maxim Integrated 功能:Inverting, Step Up 輸出電壓:- 1.5 V to - 5.5 V, 3 V to 11 V 輸出電流:100 mA 電源電流:1 mA 最大工作溫度:+ 70 C 封裝 / 箱體:SOIC-8 Narrow 封裝:Tube