收藏本站
ADT7463
http://onsemi.com
27
pullup on the gate is tied to 5 V. The MOSFET should also
have a low on resistance to ensure that there is not significant
voltage drop across the FET. This reduces the voltage
applied across the fan and therefore the maximum operating
speed of the fan.
Figure 40 shows how a 3wire fan may be driven using
PWM control.
Figure 40. Driving a 3wire Fan Using an Nchannel
MOSFET
ADT7463
TACH/AIN
PWM
Q1
NDT3055L
12 V
FAN
3.3 V
12 V
12 V
10 kW
4.7 kW
10 kW
10 kW
TACH
Figure 40 uses a 10 kW pullup resistor for the TACH
signal. This assumes that the TACH signal is opencollector
from the fan. In all cases, the TACH signal from the fan must
be kept below 5 V maximum to prevent damaging the
ADT7463. If in doubt as to whether the fan used has an
opencollector or totem pole TACH output, use one of the
input signal conditioning circuits shown in the Fan Speed
Measurement section of the data sheet.
Figure 41 shows a fan drive circuit using an NPN
transistor such as a generalpurpose MMBT2222. While
these devices are inexpensive, they tend to have much lower
current handling capabilities and higher on resistance than
MOSFETs. When choosing a transistor, care should be taken
to ensure that it meets the fans current requirements.
Ensure that the base resistor is chosen such that the
transistor is saturated when the fan is powered on.
Figure 41. Driving a 3wire Fan Using
an NPN Transistor
ADT7463
TACH/AIN
PWM
Q1
MMBT2222
12 V
FAN
3.3 V
12 V
12 V
10 kW
4.7 kW
470 W
10 kW
TACH
Driving Two Fans from PWM3
Note that the ADT7463 has four TACH inputs available
for fan speed measurement, but only three PWM drive
outputs. If a fourth fan is being used in the system, it should
be driven from the PWM3 output in parallel with the third
fan. Figure 42 shows how to drive two fans in parallel using
low cost NPN transistors. Figure 43 is the equivalent circuit
using the NDT3055L MOSFET. Note that since the
MOSFET can handle up to 3.5 A, it is simply a matter of
connecting another fan directly in parallel with the first.
Care should be taken in designing drive circuits with
transistors and FETs to ensure that the PWM pins are not
required to source current and that they sink less than the
8 mA maximum current specified on the data sheet.
Figure 42. Interfacing Two Fans in Parallel to the
PWM3 Output Using Low Cost NPN Transistors
ADT7463
PWM3
Q1
MMBT3904
3.3 V
1 kW
TACH4
2.2 kW
3.3 V
TACH3
10 W
10 W
12 V
Q2
MMBT2222
Q3
MMBT2222
Figure 43. Interfacing Two Fans in Parallel to the
PWM3 Output Using a Single Nchannel MOSFET
ADT7463
TACH4
Q1
NDT3055L
3.3 V
10 kW
TYP
TACH3
PWM3
3.3 V
3.3 V
10 kW
TYP
10 kW
TYP
+V
+V
5 V
or
12 V
FAN
TACH
5 V
or
12 V
FAN
TACH
Driving Up to Three Fans from PWM2
TACH measurements for fans are synchronized to
particular PWM channels, e.g., TACH1 is synchronized to
PWM1. TACH3 and TACH4 are both synchronized to
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*
相关PDF资料
ADT7476AARQZ-R IC REMOTE THERMAL CTLR 24QSOP
ADT7481ARMZ-1RL IC SENSOR TEMP 2CH ALARM 10MSOP
ADT7482ARMZ-REEL IC SENSOR TEMP 2CH ALARM 10MSOP
ADT7485AARMZ-R IC TEMP/VOLT DGL SENS SST 10MSOP
ADT7486AARMZ-RL IC TEMP SENS DGTL 2CH SST 10MSOP
ADT7488AARMZ-RL IC TEMP/VOLT DGTL W/SST 10MSOP
ADT7518ARQZ IC SENSOR TEMP QD ADC/DAC 16QSOP
AT30TS00-MAH-T SENSOR DGTL TEMP I2C/SMBUS 8WDFN
相关代理商/技术参数
ADT7463ARQZ-REEL7 功能描述:IC REMOTE THERMAL CTRLR 24-QSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 热管理 系列:dBCool® 标准包装:1 系列:- 功能:温度监控系统（传感器） 传感器类型:内部和外部 感应温度:-40°C ~ 125°C，外部传感器 精确度:±2.5°C 本地（最大值），±5°C 远程（最大值） 拓扑:ADC，比较器，寄存器库 输出类型:2 线 SMBus? 输出警报:无 输出风扇:无 电源电压:2.7 V ~ 5.5 V 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:SOT-23-8 供应商设备封装:SOT-23-8 包装:Digi-Reel® 其它名称:296-22675-6
ADT7466 制造商:AD 制造商全称:Analog Devices 功能描述:dBCool Remote Thermal Controller and Voltage Monitor
ADT7466ARQZ 功能描述:板上安装温度传感器 RMT THRM CTR VLT MON RoHS:否 制造商:Omron Electronics 输出类型:Digital 配置: 准确性:+/- 1.5 C, +/- 3 C 温度阈值: 数字输出 - 总线接口:2-Wire, I2C, SMBus 电源电压-最大:5.5 V 电源电压-最小:4.5 V 最大工作温度:+ 50 C 最小工作温度:0 C 关闭: 安装风格: 封装 / 箱体: 设备功能:Temperature and Humidity Sensor
ADT7466ARQZ-REEL 功能描述:板上安装温度传感器 RMT THRM CTR VLT MON RoHS:否 制造商:Omron Electronics 输出类型:Digital 配置: 准确性:+/- 1.5 C, +/- 3 C 温度阈值: 数字输出 - 总线接口:2-Wire, I2C, SMBus 电源电压-最大:5.5 V 电源电压-最小:4.5 V 最大工作温度:+ 50 C 最小工作温度:0 C 关闭: 安装风格: 封装 / 箱体: 设备功能:Temperature and Humidity Sensor
ADT7466ARQZ-REEL7 功能描述:IC REMOTE THERMAL CTRLR 16QSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 热管理 系列:dBCool® 标准包装:1 系列:- 功能:温度监控系统（传感器） 传感器类型:内部和外部 感应温度:-40°C ~ 125°C，外部传感器 精确度:±2.5°C 本地（最大值），±5°C 远程（最大值） 拓扑:ADC，比较器，寄存器库 输出类型:2 线 SMBus? 输出警报:无 输出风扇:无 电源电压:2.7 V ~ 5.5 V 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:SOT-23-8 供应商设备封装:SOT-23-8 包装:Digi-Reel® 其它名称:296-22675-6
ADT7466ARQZ-RL7 功能描述:板上安装温度传感器 RMT THRM CTR VLT MON RoHS:否 制造商:Omron Electronics 输出类型:Digital 配置: 准确性:+/- 1.5 C, +/- 3 C 温度阈值: 数字输出 - 总线接口:2-Wire, I2C, SMBus 电源电压-最大:5.5 V 电源电压-最小:4.5 V 最大工作温度:+ 50 C 最小工作温度:0 C 关闭: 安装风格: 封装 / 箱体: 设备功能:Temperature and Humidity Sensor
ADT7466ZEVB 功能描述:BOARD EVALUATION ADT7466 RoHS:是 类别:编程器，开发系统 >> 过时/停产零件编号 系列:dBCool® 标准包装:1 系列:- 传感器类型:CMOS 成像，彩色（RGB） 传感范围:WVGA 接口:I²C 灵敏度:60 fps 电源电压:5.7 V ~ 6.3 V 嵌入式:否 已供物品:成像器板 已用 IC / 零件:KAC-00401 相关产品:4H2099-ND - SENSOR IMAGE WVGA COLOR 48-PQFP4H2094-ND - SENSOR IMAGE WVGA MONO 48-PQFP
ADT7467 制造商:AD 制造商全称:Analog Devices 功能描述:dBCool Remote Thermal Monitor and Fan Controller