- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄361034 > LM79CCVF (NATIONAL SEMICONDUCTOR CORP) Microprocessor System Hardware Monitor PDF資料下載
參數(shù)資料
| 型號： | LM79CCVF |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | 模擬信號調理 |
| 英文描述： | Microprocessor System Hardware Monitor |
| 中文描述： | SPECIALTY ANALOG CIRCUIT, PQFP44 |
| 封裝： | 10 X 10 MM, PLASTIC, QFP-44 |
| 文件頁數(shù)： | 20/31頁 |
| 文件大?。?/td> | 481K |
| 代理商： | LM79CCVF |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁當前第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁
Functional Description
(Continued)
7.0 TEMPERATURE MEASUREMENT SYSTEM
The LM79 bandgap type temperature sensor and ADC per-
form 8-bit two’s-complement conversions of the tempera-
ture. A digital comparator is also incorporated that compares
the readings to the user-programmable Overtemperature
setpoint and Hysteresis values.
7.1 Temperature Data Format
Temperature data can be read from the Temperature, T
OI
Set
Point, and T
HYST
Set Point registers; and written to the T
OI
Set Point, and T
HYST
Set Point registers. Temperature data
is represented by an 8-bit, two’s complement word with an
LSB (Least Significant Bit) equal to 1.0C:
Temperature
Digital Output
Binary
0111 1101
0001 1001
0000 0001
0000 0000
1111 1111
1110 0111
1100 1001
Hex
7Dh
19h
01h
00h
FFh
E7h
C9h
+125C
+25C
+1.0C
+0C
1.0C
25C
55C
7.2 Temperature Interrupts
The normal mode for temperature interrupts in the LM79 is
an “Interrupt” mode operating in the following way: Exceed-
ing T
causes an interrupt that will remain active indefinitely
until reset by reading Interrupt Status Register 1. Once an
interrupt event has occurred by crossing T
, then reset, an
interrupt will only occur again by the temperature going
below T
. Again, it will remain active indefinitely until
being reset by reading Interrupt Status Register 1.
A “Comparator” mode for temperature interrupts can be
made available by setting the T
limit to 127C. This
results in a simple “thermostat” type of function where an
interrupt will be set whenever the temperature exceeds the
T
OI
limit. Reading Interrupt Status Register 1 will clear the
interrupt as usual, but the interrupt will set again after the
completion of another measurement cycle. It will remain set
until the temperature goes below the T
OI
limit (allow up to
two measurement cycles for clearing after descending below
T
OI
while in Comparator mode).
DS100036-18
FIGURE 10. Temperature-to-Digital Transfer Function
(Non-Linear Scale for Clarity)
DS100036-19
*
Note:
Interrupt resets occur only when interrupt Status Register 1 is read.
(a) Interrupt Mode
DS100036-20
Interrupt resets occur when Interrupt Status Register 1 is read but will set
again when monitoring cycle continues (as long as temperature exceeds
T
). When temperature descends below T
allow up to two monitoring
loops before the Temperature Interrupt resets.
(b) Comparator Mode
FIGURE 11. Temperature Interrupt Response Diagram
L
www.national.com
20
相關PDF資料 |
PDF描述 |
|---|---|
| LM79 | |
| LM81CIMTX-32 | Serial Interface ACPI-Compatible Microprocessor System |
| LM81 | Serial Interface ACPI-Compatible Microprocessor System |
| LM81CIMT-31 | Serial Interface ACPI-Compatible Microprocessor System |
| LM82CIMQAX | Remote Diode and Local Digital Temperature Sensor with Two-Wire Interface |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| LM79GCP | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Negative Adjustable Voltage Regulator |
| LM79L | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:3-Terminal Negative Regulators |
| LM79L00 | 制造商:FCI 制造商全稱:First Components International 功能描述:LM79L00 Series 3-Terminal Negative Output voltage Regulators |
| LM79L05 | 制造商:KEXIN 制造商全稱:Guangdong Kexin Industrial Co.,Ltd 功能描述:Three-terminal negative voltage regulator |
| LM79L05A | 制造商:FAIRCHILD 制造商全稱:Fairchild Semiconductor 功能描述:3-Terminal 0.1A Negative Voltage Regulator |
發(fā)布緊急采購，3分鐘左右您將得到回復。