Hardware Hacking

LM75A Description
Digital temperature sensor and thermal Watchdog(tm)
LM75A Vendor
Philips Semiconductors
LM75A Categories
Digital Thermometers & Thermostats

LM75A Features
Pin-for-pin replacement for industry standard LM75 and offers improved temperature resolution of 0.125 Cel. and specification of a single part over power supply range from 2.8 V to 5.5 V.
Small 8-pin package types: SO8 and TSSOP8
I²C-bus interface with up to 8 devices on the same bus
Power supply range from 2.8 V to 5.5 V
Temperatures range from -55 Cel. to +125 Cel.
11-bit ADC that offers a temperature resolution of 0.125 Cel.
Temperature accuracy of +- 2 Cel. from -25 Cel. to +100 Cel.
Programmable temperature threshold and hysteresis set points
Supply current of 3.5 uA in shut-down mode for power conservation
Stand-alone operation as thermostat at power-up.

LM75A Datasheet and Application Notes
LM75A Datasheet

Products related to LM75A
LM75AD LM75ADP

DS75 Description
Digital Thermometer and Thermostat
DS75 Vendor
Maxim
DS75 Categories
Digital Thermometers & Thermostats

DS75 Features
FEATURES
Temperature Measurements Require No External Components
Measures Temperatures from -55°C to +125°C (-67°F to +257°F)
±2°C Accuracy Over a -25°C to +100°C Range
Thermometer Resolution is User-Configurable from Nine (Default) to 12 Bits (0.5°C to 0.0625°C Resolution)
9-Bit Conversion Time is 150ms (Max)
Thermostatic Settings are User-Definable
Data is Read/Written Via 2-Wire Serial (Interface (SDA and SCL Pins)
Multidrop Capability Simplifies Distributed Temperature-Sensing Applications
Wide Power-Supply Range (+2.7V to +5.5V).
Pin/software Compatible with the LM75
Available in 8-Pin µMAX and SO Packages and as a 1.5mm x 1.3mm Flip Chip. See Table 1 for Ordering Information
Applications Include Personal Computers, Cellular Base Stations, Office Equipment, or Any Thermally Sensitive System

DS75 Datasheet and Application Notes
DS75 Datasheet

Parameter Value
Interface 2-Wire/SMBus
Accuracy (±°C) 2
Supply Voltage Range (V) 2.7-5.5
Op. Range (°C) -55 to +125
Temp. Thresh. (°C) 1, Prog.
Meas. Res. (Bits) 9 - 12
Package 8/µMAX (µSOP)
Package 8/SO.150
Package FlipChip

DS1921L-F5X Description
Thermochron iButton
DS1921L-F5X Vendor
Maxim
DS1921L-F5X Categories
Digital Thermometers & Thermostats

DS1921L-F5X Features
Digital Thermometer Measures Temperature in 0.5°C Increments
Built-In Real-Time Clock (RTC) and Timer has Accuracy of ±2 Minutes per Month from 0°C to 45°C
Automatically Wakes Up and Measures Temperature at User-Programmable Intervals From 1 to 255 Minutes
Logs up to 2048 consecutive temperature measurements in protected nonvolatile (NV) memory
Records a Long-Term Temperature Histogram With 2.0°C Resolution
Programmable Temperature-High and Temperature-Low Alarm Trip Points
Records Up to 24 Time Stamps and Durations when Temperature Leaves the Range Specified by the Trip Points
512 Bytes of General-Purpose Read/Write NV Memory
Communicates to Host with a Single Digital Signal at 14.1kb or 125kbps Using 1-Wire Protocol
COMMON iButton FEATURES
Digital Identification and Information by Momentary Contact
Unique, Factory-Lasered and Tested 64-Bit Registration Number (8-Bit Family Code + 48-Bit Serial Number + 8-Bit CRC Tester) Assures Absolute Traceability Because no Two Parts are alike
Multidrop Controller for 1-Wire Net
Chip-Based Data Carrier Compactly Stores Information
Data Can be Accessed While Affixed to Object
Button Shape is Self-Aligning with Cup-Shaped Probes
Durable Stainless Steel Case Engraved with Registration Number Withstands Harsh Environments
Easily Affixed with Self-Stick Adhesive Backing, Latched by its Flange, or Locked with a Ring Pressed Onto its Rim
Presence Detector Acknowledges When Reader First Applies Voltage
Meets UL#913 (4th Edit.). Intrinsically Safe Apparatus: Approved Under Entity Concept for Use in Class I, Division 1, Group A, B, C and D Locations (application pending)

DS1921L-F5X Datasheet and Application Notes
DS1921L-F5X Datasheet

Parameter Value
Memory Type NV RAM
Memory Size 4096
Package F5

DS1921Z Description
High Resolution Thermochron iButton Range H: +15°C to +46°C; Z: -5°C to +26°C
DS1921Z Vendor
Maxim
DS1921Z Categories
Digital Thermometers & Thermostats

DS1921Z Features
Digital thermometer measures temperature 1/8°C increments with ±1°C accuracy
Built-in real-time clock (RTC) and timer has accuracy of ±2 minutes per month from 0°to 45°C
Automatically wakes up and measures temperature at user-programmable intervals from 1 to 255 minutes
Logs up to 2048 consecutive temperature measurements in protected nonvolatile (NV) random access memory
Records a long-term temperature histogram with 1/2°C resolution
Programmable temperature-high and temperature-low alarm trip points
Records up to 24 time stamps and durations when temperature leaves the range specified by the trip points
512 bytes of general-purpose read/write NV random access memory
Communicates to host with a single digital signal at 15.4kbits or 125kbits per second using 1-Wire ® protocol
Fixed range: H: +15°C to +46°C; Z: -5°C to +26°C
Common iButton features:
Digital identification and information by momentary contact
Unique, factory-lasered and tested 64-bit registration number (8-bit family code + 48-bit serial number + 8-bit CRC tester) assures absolute traceability because no two parts are alike
Multidrop controller for 1-Wire net Chip-based data carrier compactly stores information
Data can be accessed while affixed to object
Button shape is self-aligning with cup-shaped probes
Durable stainless steel case engraved with registration number withstands harsh environments
Easily affixed with self-stick adhesive backing, latched by its flange, or locked with a ring pressed onto its rim
Presence detector acknowledges when reader first applies voltage
Meets UL#913 (4th Edit.). Intrinsically Safe Apparatus: approved under Entity Concept for use in Class I, Division 1, Group A, B, C, and D Locations (application pending)

DS1921Z Datasheet and Application Notes
DS1921Z Datasheet

Parameter Value
Memory Type NV RAM
Memory Size 4K bits
Temperature Logger -5C to +26C
Other ±1°C Accuracy
0.125°C Resolution
2048-Byte Temperature Log
63-bin Temperature Histogram
High/Low Temperature Alarms

Package F5
Price @ 1k $8.50
Products related to DS1921Z
DS1921H

DS1921G Description
Thermochron iButton
DS1921G Vendor
Maxim
DS1921G Categories
Digital Thermometers & Thermostats

DS1921G Features
Digital thermometer measures temperature 0.5°C increments
Accuracy ±1°C from -30°C to +70°C. See EC table for accuracy specification
Built-in real-time clock (RTC) and timer has accuracy of ±2 minutes per month per month from 0°C to 45°C
Automatically wakes up and measures temperature at user-programmable intervals from 1 to 255 minutes
Logs up to 2048 consecutive temperature measurements in protected nonvolatile (NV) random access memory
Records a long-term temperature histogram with 2.0°C resolution
Programmable temperature-high and temperature-low alarm trip points
Records up to 24 time stamps and durations when temperature leaves the range specified by the trip points
512 bytes of general-purpose read/write NV random access memory
Communicates to host with a single digital signal at 15.4kbits or 125kbits per second using 1-Wire ® protocol
Common iButton features:
Digital identification and information by momentary contact
Unique, factory-lasered and tested 64-bit reg-istration number (8-bit family code + 48-bit serial number + 8-bit CRC tester) assures ab-solute traceability because no two parts are alike
Multidrop controller for 1-Wire net
Chip-based data carrier compactly stores information
Data can be accessed while affixed to object
Button shape is self-aligning with cup-shaped probes
Durable stainless-steel case engraved with registration number withstands harsh environments
Easily affixed with self-stick adhesive backing, latched by its flange, or locked with a ring pressed onto its rim
Presence detector acknowledges when reader first applies voltage
Meets UL#913 (4th Edit.). Intrinsically Safe Apparatus: approved under Entity Concept for use in Class I, Division 1, Group A, B, C and D Locations (application pending)

DS1921G Datasheet and Application Notes
DS1921G Datasheet

Parameter Value
Memory Type NV RAM
Memory Size 4K bits
Temperature Logger -40C to +85C
Other ±1°C Accuracy -30C to 70C, ±1.3C outside this band
0.5°C Resolution
2048-Byte Temperature Log
63-bin Temperature Histogram
High/Low Temperature Alarms

Package F5
Price @ 1k $9.50