- 您现在的位置：买卖IC网 > PDF目录17116 > LM89-1EVAL (National Semiconductor)BOARD EVALUATION LM89-1 PDF资料下载
参数资料
| 型号： | LM89-1EVAL |
| 厂商： | National Semiconductor |
| 文件页数： | 10/32页 |
| 文件大小： | 0K |
| 描述： | BOARD EVALUATION LM89-1 |
| 标准包装： | 1 |
| 传感器类型： | 温度 |
| 传感范围： | 0°C ~ 125°C |
| 接口： | SMBus（2 线/I²C） |
| 灵敏度： | ±1°C |
| 电源电压： | 3 V ~ 3.6 V |
| 嵌入式： | 否 |
| 已供物品： | 板，CD |
| 已用 IC / 零件： | LM89-1 |
| 相关产品： | LM89-1CIMX-ND - IC TEMP SENSOR DGTL 8-SOIC LM89-1CIMM/NOPBTR-ND - IC TEMP SENSOR DGTL 8-MSOP LM89-1CIMMX/NOPBTR-ND - IC TEMP SENSOR DGTL 8-MSOP LM89-1CIM-ND - IC TEMP SENSOR DGTL 8-SOIC |
第1页第2页第3页第4页第5页第6页第7页第8页第9页当前第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页
SNIS128C – AUGUST 2002 – REVISED MARCH 2013
3. LM89 clears STATUS REGISTER, resets the ALERT HIGH and sets the ALERT mask bit (D7 in the
Configuration register).
4. Master attends to conditions that caused the ALERT to be triggered. The fan is started, setpoint limits are
adjusted, etc.
5. Master resets the ALERT mask (D7 in the Configuration register).
RDTS Measurement
Remote High Limit
LM89 ALERT pin
ALERT mask set in
response to reading of
status register by
master
End of Temperature
conversion
Status Register: RTDS High
TIME
Figure 5. ALERT Output as an Interrupt Temperature Response Diagram
ALERT Output as an SMBus ALERT
When the ALERT output is connected to one or more ALERT outputs of other SMBus compatible devices and to
a master, an SMBus alert line is created. Under this implementation, the LM89's ALERT should be operated
using the ARA (Alert Response Address) protocol. The SMBus 2.0 ARA protocol, defined in the SMBus
specification 2.0, is a procedure designed to assist the master in resolving which part generated an interrupt and
service that interrupt while impeding system operation as little as possible.
The SMBus alert line is connected to the open-drain ports of all devices on the bus thereby AND'ing them
together. The ARA is a method by which with one command the SMBus master may identify which part is pulling
the SMBus alert line LOW and prevent it from pulling it LOW again for the same triggering condition. When an
ARA command is received by all devices on the bus, the devices pulling the SMBus alert line LOW, first, send
their address to the master and second, release the SMBus alert line after recognizing a successful transmission
of their address.
The SMBus 1.1 and 2.0 specification state that in response to an ARA (Alert Response Address) “after
acknowledging the slave address the device must disengage its SMBALERT pulldown”. Furthermore, “if the host
still sees SMBALERT low when the message transfer is complete, it knows to read the ARA again”. This SMBus
“disengaging of SMBALERT” requirement prevents locking up the SMBus alert line. Competitive parts may
address this “disengaging of SMBALERT” requirement differently than the LM89 or not at all. SMBus systems
that implement the ARA protocol as suggested for the LM89 will be fully compatible with all competitive parts.
The LM89 fulfills “disengaging of SMBALERT” by setting the ALERT mask bit (bit D7 in the Configuration
register, at address 09h) after successfully sending out its address in response to an ARA and releasing the
ALERT output pin. Once the ALERT mask bit is activated, the ALERT output pin will be disabled until enabled by
software. In order to enable the ALERT the master must read the STATUS REGISTER, at address 02h, during
the interrupt service routine and then reset the ALERT mask bit in the Configuration register to 0 at the end of
the interrupt service routine.
The following sequence describes the ARA response protocol.
1. Master Senses SMBus alert line low
2. Master sends a START followed by the Alert Response Address (ARA) with a Read Command.
3. Alerting Device(s) send ACK.
4. Alerting Device(s) send their Address. While transmitting their address, alerting devices sense whether their
address has been transmitted correctly. (The LM89 will reset its ALERT output and set the ALERT mask bit
once its complete address has been transmitted successfully.)
10
Product Folder Links: LM89
Copyright ? 2002–2013, Texas Instruments Incorporated
相关PDF资料 |
PDF描述 |
|---|---|
| KITMPR083EVM | KIT EVAL 8POSITION ROTARY TOUCH |
| RCC12DREN-S734 | CONN EDGECARD 24POS .100 EYELET |
| VE-J7P-EZ | CONVERTER MOD DC/DC 13.8V 25W |
| GBM28DSEN | CONN EDGECARD 56POS .156 EYELET |
| ADR06WARZ-RL | IC VREF SERIES PREC 3V 8SOIC |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LM8942 | 制造商:未知厂家 制造商全称:未知厂家 功能描述: |
| LM8972 | 制造商:未知厂家 制造商全称:未知厂家 功能描述: |
| LM89CIM | 制造商:Rochester Electronics LLC 功能描述: 制造商:Texas Instruments 功能描述: |
| LM89CIM/NOPB | 功能描述:IC TEMP SENSOR DGTL 8-SOIC RoHS:是 类别:集成电路 (IC) >> PMIC - 热管理 系列:- 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 |
| LM89CIMM | 功能描述:板上安装温度传感器 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 |
发布紧急采购，3分钟左右您将得到回复。