參數(shù)資料
型號: MAX6639FATE+
廠商: Maxim Integrated
文件頁數(shù): 16/22頁
文件大小: 234K
描述: IC 2CH TEMP MONITOR 16TQFN
產(chǎn)品培訓模塊: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
標準包裝: 60
功能: 風扇控制,溫度監(jiān)控器
傳感器類型: 內(nèi)部和外部
感應溫度: 0°C ~ 150°C,外部傳感器
精確度: -2.5°C 本地(最大),±1°C 遠程(最大)
拓撲: ADC,PWM 發(fā)生器,轉速計計數(shù)器
輸出類型: I²C?/SMBus?
輸出警報:
輸出風扇:
電源電壓: 3 V ~ 3.6 V
工作溫度: -40°C ~ 125°C
安裝類型: 表面貼裝
封裝/外殼: 16-WQFN 裸露焊盤
供應商設備封裝: 16-TQFN-EP(5x5)
包裝: 管件
Fan 1 and 2 Pulses and Min RPM (24h and 25h)
D[7:6]: This sets the number of tachometer pulses per
revolution for the fan. When set properly, a 2000RPM fan
with two pulses per revolution has the same tachometer
count as a 2000RPM fan with four pulses per revolution.
Table 10 lists tachometer pulses per revolution.
D[5:0]: This sets the minimum allowable fan tachometer
count (maximum speed). This limits the maximum
speed of the fan to reduce noise at high temperatures.
For reasonable speed resolution, the fan RPM range
should be set so this value is between approximately
30 and 60. If a maximum RPM limit is unnecessary, this
value can be set to the full-speed tachometer count.
Fan 1 and 2 Duty Cycle (26h and 27h)
These registers contain the present value of the PWM
duty cycle. In PWM fan-control mode, the desired (tar-
get) value of the PWM duty cycle can be written directly
into this register.
Channel 1 and Channel 2 Fan-Start Temperature
(28h and 29h)
These registers contain the temperatures at which fan
control begins (in automatic RPM mode).
Applications Information
Fan-Drive Circuits
A variety of fan-drive circuit configurations can be used
with the MAX6639 to control the fans speed. Four of
the most common are shown in Figures 6 through 10.
PWM Power-Supply Drive (High Side or Low Side)
The simplest way to control the speed of a 3-wire (sup-
ply, ground, and tachometer output) fan is to modulate
its power supply with a PWM signal. The PWM frequen-
cy is typically in the 20Hz to 40Hz range, with 33Hz
being a common value. If the frequency is too high, the
fans internal control circuitry does not have sufficient
time to turn on during a power-supply pulse. If the fre-
quency is too low, the power-supply modulation
becomes more easily audible.
The PWM can take place on the high side (Figure 6) or
the low side (Figure 7) of the fans power supply. In
either case, if the tachometer is used, it is usually nec-
essary to periodically stretch a PWM pulse so there is
enough time to count the tachometer pulse edges for
speed measurement. The MAX6639 allows this pulse
stretching to be enabled or disabled to match the
needs of the application.
Pulse stretching can sometimes be audible if the fan
responds quickly to changes in the drive voltage. If the
acoustic effects of pulse stretching are too noticeable,
2-Channel Temperature Monitor with Dual,
Automatic, PWM Fan-Speed Controller
16
Maxim Integrated
MAX6639/MAX6639F
REGISTERS 24h
OR 25h D[7:6]
TACHOMETER PULSES PER
REVOLUTION
00
1
01
2
10
3
11
4
Table 10. Tachometer Pulses per
Revolution
V
CC
PWM1
4.7k?/DIV>
4.7k?/DIV>
TACH1
3V TO 5.5V
TACH
OUTPUT
V
FAN
(5V OR 12V)
Figure 6. High-Side PWM Drive Circuit
V
CC
TACH1
4.7k?/DIV>
4.7k?/DIV>
PWM1
3V TO 5.5V
3V TO 5.5V
TACH
OUTPUT
V
FAN
(5V OR 12V)
Figure 7. Low-Side Drive Circuit
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相關代理商/技術參數(shù)
參數(shù)描述
MAX6639FATE+ 功能描述:板上安裝溫度傳感器 2Ch Temperature Monitor RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準確性:+/- 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 關閉: 安裝風格: 封裝 / 箱體: 設備功能:Temperature and Humidity Sensor
MAX6639FATE+T 功能描述:板上安裝溫度傳感器 2Ch Temperature Monitor RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準確性:+/- 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 關閉: 安裝風格: 封裝 / 箱體: 設備功能:Temperature and Humidity Sensor
MAX6639YAEE+ 功能描述:板上安裝溫度傳感器 2Ch Temperature Monitor RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準確性:+/- 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 關閉: 安裝風格: 封裝 / 箱體: 設備功能:Temperature and Humidity Sensor
MAX6639YAEE+T 功能描述:板上安裝溫度傳感器 2Ch Temperature Monitor RoHS:否 制造商:Omron Electronics 輸出類型:Digital 配置: 準確性:+/- 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 關閉: 安裝風格: 封裝 / 箱體: 設備功能:Temperature and Humidity Sensor
MAX663C/D 功能描述:低壓差穩(wěn)壓器 - LDO RoHS:否 制造商:Texas Instruments 最大輸入電壓:36 V 輸出電壓:1.4 V to 20.5 V 回動電壓(最大值):307 mV 輸出電流:1 A 負載調(diào)節(jié):0.3 % 輸出端數(shù)量: 輸出類型:Fixed 最大工作溫度:+ 125 C 安裝風格:SMD/SMT 封裝 / 箱體:VQFN-20