DS18B20 datasheet(3/21 Pages) DALLAS

Part #	DS18B20

Description	Programmable Resolution 1-Wire Digital Thermometer

PDF	21 Pages

Scroll/Zoom	100%

Manufacturer	DALLAS [Dallas Semiconductor]

Direct Link	https://www.maximintegrated.com/en.html

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DS18B20

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Another feature of the DS18B20 is the ability to operate without an external power supply. Power is

instead supplied through the 1-Wire pullup resistor via the DQ pin when the bus is high. The high bus

signal also charges an internal capacitor (CPP), which then supplies power to the device when the bus is

low. This method of deriving power from the 1-Wire bus is referred to as “parasite power.” As an

alternative, the DS18B20 may also be powered by an external supply on VDD.

DS18B20 BLOCK DIAGRAM Figure 1

VPU

4.7k

POWER

SUPPLY

SENSE

64-BIT ROM

AND

1-wire PORT

VDD

INTERNAL VDD

CPP

PARASITE POWER

CIRCUIT

MEMORY CONTROL

LOGIC

SCRATCHPAD

8-BIT CRC GENERATOR

TEMPERATURE SENSOR

ALARM HIGH TRIGGER (TH)

ALARM LOW TRIGGER (TL)

CONFIGURATION REGISTER

(EEPROM)

GND

DS18B20

DS18B20 Datasheet(PDF) 3 Page - Dallas Semiconductor