- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄97865 > DS1821 (DALLAS SEMICONDUCTOR) DIGITAL TEMP SENSOR-SERIAL, 8BIT(s), 1Cel, ROUND, SURFACE MOUNT PDF資料下載
參數(shù)資料
| 型號： | DS1821 |
| 廠商： | DALLAS SEMICONDUCTOR |
| 元件分類： | Switch/Digital Output Temperature Sensor |
| 英文描述： | DIGITAL TEMP SENSOR-SERIAL, 8BIT(s), 1Cel, ROUND, SURFACE MOUNT |
| 封裝： | PR-35, 3 PIN |
| 文件頁數(shù)： | 10/17頁 |
| 文件大小： | 461K |
| 代理商： | DS1821 |
DS1821
Page 2 of 17
DETAILED PIN DESCRIPTIONS Table 1
PR35
8-PIN
SOIC*
SYMBOL
DESCRIPTION
1
2
GND
Ground pin.
21
DQ
Open drain data input/output pin – 1-wire operation; Open drain
thermostat output pin –thermostat operation.
38
VDD
Power supply pin.
*All pins not specified in this table are “No Connect” pins.
OVERVIEW
Figure 1 shows a block diagram of the DS1821 and pin descriptions are given in Table 1. The DS1821
can operate as a standalone thermostat with user-programmable trip-points or as 8-bit temperature sensor
with a 1-wire digital interface. The open-drain DQ pin functions as the thermostat output for thermostat
operation and as the data I/O pin for 1-wire communications. The 1-wire interface provides user access to
the nonvolatile (EEPROM) thermostat trip-point registers (TH and TL), the status/configuration register,
and the temperature register.
When configured as standalone thermostat, temperature conversions start immediately at power-up. In
this mode, the DQ pin becomes active when the temperature of the DS1821 exceeds the limit
programmed into the TH register, and remains active until the temperature drops below the limit
programmed into the TL register.
The DS1821 uses Dallas’ exclusive 1-wire bus protocol that implements bus communication with one
control signal. This system is explained in detail in the 1-WIRE BUS SYSTEM section of this datasheet.
DS1821 BLOCK DIAGRAM Figure 1
TEMPERATURE SENSOR FUNCTIONALITY
The core functionality of the DS1821 is its proprietary direct-to-digital temperature sensor, which
provides 8-bit (1°C increment) centigrade temperature readings over the range of -55°C to +125°C.
A block diagram of the temperature measurement circuitry is shown in Figure 2. This circuit measures
the temperature by counting the number of clock cycles generated by an oscillator with a low temperature
coefficient (temp-co) during a gate period determined by a high temp-co oscillator. The low temp-co
VDD
4.7K
DQ
GND
TH REGISTER
TL REGISTER
CONFIGURATION REGISTER
AND CONTROL LOGIC
TEMPERATURE SENSOR
1-WIRE
INTERFACE
AND
I/O CONTROL
VDD
POWER
SUPPLY
SENSE
DIGITAL
COMPARATOR/
LOGIC
DS1821
相關PDF資料 |
PDF描述 |
|---|---|
| DS1821T | DIGITAL TEMP SENSOR-SERIAL, 8BIT(s), RECTANGULAR, THROUGH HOLE MOUNT |
| DS1822-PAR+T&R | DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 2Cel, RECTANGULAR, THROUGH HOLE MOUNT |
| DS1822-PAR/T&R | DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 2Cel, RECTANGULAR, THROUGH HOLE MOUNT |
| DS1822-PAR | DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 0.20Cel, ROUND, THROUGH HOLE MOUNT |
| DS1822Z/T&R | DIGITAL TEMP SENSOR-SERIAL, 12BIT(s), 2Cel, RECTANGULAR, SURFACE MOUNT |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| DS1821_07 | 制造商:DALLAS 制造商全稱:Dallas Semiconductor 功能描述:Programmable Digital Thermostat and Thermometer |
| DS1821+ | 功能描述:板上安裝溫度傳感器 Programmable Digital Thermostat/Thrmmtr 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 |
| DS1821C+ | 功能描述:恒溫器 Programmable Digital Thermo-stat/monitor RoHS:否 制造商:Maxim Integrated 功能: 開路溫度: 閉合溫度: 準確性:+/- 1 C 溫度范圍:- 55 C to + 125 C 電流額定值:500 uA 電壓額定值:2.7 V to 5.5 V 產(chǎn)品:Thermostats |
| DS1821-C02 | 功能描述:板上安裝溫度傳感器 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 |
| DS1821-C04 | 制造商:DSC 功能描述: |
發(fā)布緊急采購，3分鐘左右您將得到回復。