参数资料
型号: MAX6639FATE+
厂商: Maxim Integrated
文件页数: 8/22页
文件大小: 234K
描述: IC 2CH TEMP MONITOR 16TQFN
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 60
功能: 风扇控制,温度监控器
传感器类型: 内部和外部
感应温度: 0°C ~ 150°C,外部传感器
精确度: -2.5°C 本地(最大),±1°C 远程(最大)
拓扑: ADC,PWM 发生器,转速计计数器
输出类型: I²C?/SMBus?
输出警报:
输出风扇:
电源电压: 3 V ~ 3.6 V
工作温度: -40°C ~ 125°C
安装类型: 表面贴装
封装/外壳: 16-WQFN 裸露焊盘
供应商设备封装: 16-TQFN-EP(5x5)
包装: 管件
The MAX6639 employs a register lock mechanism to
avoid getting temperature results from the temperature
register and the extended temperature register sam-
pled at two different time points. Reading the extended
register stops the MAX6639 from updating the tempera-
ture register for at least 0.25s, unless there is a temper-
ature register read before the scheduled update. This
allows enough time to read the main register before it is
updated, thereby preventing reading the temperature
register data from one conversion and the extended
temperature register data from a different conversion.
The MAX6639 measures the temperature at a fixed rate
of 4Hz immediately after it is powered on. Setting bit 7
of the configuration register (04h) shuts down the tem-
perature measurement cycle.
OT Output
When a measured temperature exceeds the corre-
sponding OT temperature threshold and OT is not
masked, the associated OT status register bit sets and
the OT output asserts. If OT for the respective channel
is masked, the OT status register sets, but the OT out-
put does not assert. To deassert the OT output and the
associated status register bit, either the measured tem-
perature must fall at least 5癈 below the trip threshold
or the trip threshold must be increased to at least 5癈
above the current measured temperature.
THERM
When a measured temperature exceeds the corre-
sponding THERM temperature threshold and THERM is
not masked, the associated THERM status register bit
is set and the THERM output asserts. If THERM for the
respective channel is masked, the THERM status regis-
ter is set, but the THERM output does not assert. To
deassert the THERM output and the associated status
register bit, either the measured temperature must fall
at least 5癈 below the trip threshold or the trip threshold
must be increased to at least 5癈 above the current
measured temperature. Asserting THERM internally or
externally forces both PWM outputs to 100% duty cycle
when bit 6 in address 13h (fan 1) or bit 6 in address
17h (fan 2) is set.
ALERT
The ALERT output asserts to indicate that a measured
temperature exceeds the ALERT trip threshold for that
temperature channel. The status bit and the ALERT out-
put clear by reading the ALERT status register. If the
ALERT status bit is cleared, but the temperature still
exceeds the ALERT temperature threshold, ALERT
reasserts on the next conversion, and the status bit sets
again. A successful alert response protocol clears
ALERT but does not affect the ALERT status bit.
TACH1 and TACH2 Inputs
To measure the fan speed, the MAX6639 has two
tachometers. Each tachometer has an accurate internal
clock to count the time elapsed in one revolution.
Therefore, it is counting the time between two tachome-
ter pulses for a fan with four poles. When the PWM sig-
nal is used to directly modulate the fans power supply,
the PWM frequency is normally in the 20Hz to 100Hz
range. In this case, the time required for one revolution
may be longer than the PWM on-time. For this reason,
the PWM pulses are periodically stretched to allow
tachometer measurement over a full revolution. Turn off
pulse stretching by setting bit 5 of register 13h or regis-
ter 17h when using a 4-wire fan.
The tachometer count is inversely proportional to the
fans RPM. The tachometer count data is stored in regis-
ter 20h (for TACH1) and register 21h (for TACH2).
Reading a value of 255 from the TACH count register
means the fans RPM is zero or too slow for the range.
Reading a value of zero in the TACH count register
means the fans RPM is higher than the range selected.
Table 2 shows the fans available RPM ranges. Use reg-
isters 10h or 14h to select the appropriate RPM range for
the fan being used.
FANFAIL
The FANFAIL output asserts to indicate that one of the
fans has failed or is spinning slower than the required
speed. The MAX6639 detects fan fault depending on the
fan-control mode. In PWM mode, the MAX6639 pro-
duces a square wave with a duty cycle set by the value
2-Channel Temperature Monitor with Dual,
Automatic, PWM Fan-Speed Controller
8
Maxim Integrated
MAX6639/MAX6639F
TEMP (?/SPAN>C)
TEMP (?/SPAN>C)
DIGITAL OUTPUT
241
+241
1111 0001
240
+240
1111 0000
126
+126
0111 1110
25
+25
0001 1001
1.50
1
0000 0001
0.00
0
0000 0000
Table 2. Temperature Data Byte Format
FAN RPM
RANGE
INTERNAL CLOCK
FREQUENCY (kHz)
2000
1
4000
2
8000
4
16,000
8
Table 3. Tachometer Setting
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相关代理商/技术参数
参数描述
MAX6639FATE+ 功能描述:板上安装温度传感器 2Ch Temperature Monitor 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
MAX6639FATE+T 功能描述:板上安装温度传感器 2Ch Temperature Monitor 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
MAX6639YAEE+ 功能描述:板上安装温度传感器 2Ch Temperature Monitor 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
MAX6639YAEE+T 功能描述:板上安装温度传感器 2Ch Temperature Monitor 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
MAX663C/D 功能描述:低压差稳压器 - LDO RoHS:否 制造商:Texas Instruments 最大输入电压:36 V 输出电压:1.4 V to 20.5 V 回动电压(最大值):307 mV 输出电流:1 A 负载调节:0.3 % 输出端数量: 输出类型:Fixed 最大工作温度:+ 125 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-20