DS1631AU ,High-precision digital thermometer and thermostatPIN DESCRIPTIONPIN SYMBOL DESCRIPTION1 SDA Data Input/Output Pin for 2-Wire Serial Communication Po ..
DS1631AU+ ,High-Precision Digital Thermometer and ThermostatApplicationsDS1631A Only) and the 8-Pin DIP (DS1631 Only) ● Network Routers and Switches Packages ● ..
DS1631S+ ,High-Precision Digital Thermometer and ThermostatPin Descriptions.(DS1631U+, DS1631AU+, DS1731U+)+SDA 1 8VDDDS1631SCL 2 7A03 6T AOUT 1GND 4 5A2SO (1 ..
DS1631U+ ,High-Precision Digital Thermometer and ThermostatApplicationsa -55°C to +125°C range. The DS1631 and DS1631A • Operating Temperature Range: -55°C to ..
DS1631Z ,High-precision digital thermometer and thermostatPin descriptions for the DS1631/DS1631A/DS1731 are provided in Table 2 and user-accessible register ..
DS1631Z+ ,High-Precision Digital Thermometer and ThermostatElectrical Characteristics(V = 2.7V to 5.5V; T = -55°C to +125°C.)DD APARAMETER SYMBOL CONDITION MI ..
DTTI5516AUA ,DTTI5516 SINGLE MODULE DEMODULATOR AND DECODER IC FOR DIGITAL VIDEO SET-TOP BOXES Data Briefing®DTTi5516Single module demodulator and decoder ICfor digital video set-top boxesDATA BRIEFDescripti ..
DTV110 ,CRT HORIZONTAL DEFLECTION HIGH VOLTAGE DAMPER DIODEFEATURES AND BENEFITSHIGH BREAKDOWN VOLTAGE CAPABILITYISOWATT220ACTO-220ACVERY FAST RECOVERY DIODED ..
DTV110F ,CRT HORIZONTAL DEFLECTION HIGH VOLTAGE DAMPER DIODEFEATURES AND BENEFITSHIGH BREAKDOWN VOLTAGE CAPABILITYISOWATT220ACTO-220ACVERY FAST RECOVERY DIODED ..
DTV1500 ,CRT HORIZONTAL DEFLECTION HIGH VOLTAGE DAMPER DIODEABSOLUTE MAXIMUM RATINGSSymbol Parameter Value UnitV Repetitive peak reverse voltage 1500 VRRMI RMS ..
DTV1500H ,HIGH VOLTAGE DAMPER DIODE (CRT HORIZONTAL DEFLECTION)ABSOLUTE MAXIMUM RATINGSSymbol Parameter Value UnitV Repetitive peak reverse voltage 1500 VRRMI RMS ..
DTV1500HD ,HIGH VOLTAGE DAMPER DIODE (CRT HORIZONTAL DEFLECTION)ABSOLUTE MAXIMUM RATINGSSymbol Parameter Value UnitV Repetitive peak reverse voltage 1500 VRRMI RMS ..
DS1631AU-DS1631Z
High-Precision Digital Thermometer and Thermostat
FEATURESDS1631 and DS1631A Provide �0.5°C
Accuracy over a 0°C to +70°C RangeDS1731 Provides �1°C Accuracy over a
-10°C to +85°C RangeDS1631A Automatically Begins Taking
Temperature Measurements at Power-UpOperating Temperature Range: -55°C to+125°C (-67°F to +257°F)Temperature Measurements Require No
External ComponentsOutput Resolution is User-Selectable to 9,
10, 11, or 12 BitsWide Power-Supply Range (+2.7V to +5.5V)Converts Temperature-to-Digital Word in
750ms (max)Multidrop Capability Simplifies Distributed
Temperature-Sensing ApplicationsThermostatic Settings are User-Definable
and Nonvolatile (NV)Data is Read/Written Through 2-Wire Serial
Interface (SDA and SCL Pins)All Three Devices are Available in 8-Pin
�SOP Packages and the DS1631 is Also
Available in a 150mil SO package—see
Table 1 for Ordering Information
PIN CONFIGURATIONS
DESCRIPTIONThe DS1631, DS1631A, and DS1731 digital thermometers provide 9, 10, 11, or 12-bit temperature
readings over a -55°C to +125°C range. The DS1631 and DS1631A thermometer accuracy is �0.5°C
from 0°C to +70°C with 3.0V � VDD � 5.5V, and the DS1731 accuracy is �1°C from -10°C to +85°C with
3.0V � VDD � 5.5V. The thermostat on all three devices provides custom hysteresis with user-defined trip
points (TH and TL). The TH and TL registers and thermometer configuration settings are stored in NV
EEPROM so they can be programmed prior to installation. In addition, the DS1631A automaticallybegins taking temperature measurements at power-up, which allows it to function as a stand-alone
thermostat. Communication with the DS1631/DS1631A/DS1731 is achieved through a 2-wire serial
interface, and three address pins allow up to eight devices to be multidropped on the same 2-wire bus.
DS1631/DS1631A/DS1731
High-Precision Digital
Thermometer and ThermostatSO (150mil)
(DS1631Z)
VDDGND
TOUT
(DS1631U, DS1631AU, DS1731U)
VDDGND
TOUT
See Table 2 for Pin Descriptions
APPLICATIONSNetwork Routers and SwitchesCellular Base StationsPortable ProductsAny Space-Constrained Thermally Sensitive
Product
DS1631/DS1631A/DS1731
Table 1. ORDERING INFORMATION
Table 2. DETAILED PIN DESCRIPTION
Figure 1. FUNCTIONAL DIAGRAMSCL
TOUT
VDD
GND
DS1631/DS1631A/DS1731
ABSOLUTE MAXIMUM RATINGS*Voltage on any Pin Relative to Ground-0.5V to +6.0VOperating Temperature Range-55°C to +125°C
Storage Temperature Range-55°C to +125°C
Solder Dip Temperature (10s)See IPC/JEDEC J-STD-020A Specification
Reflow Oven Temperature+220°C
* These are stress ratings only and functional operation of the device at these or any other conditions
above those indicated in the operation sections of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods of time may affect reliability.
DC ELECTRICAL CHARACTERISTICS(VDD = 2.7V to 5.5V; TA = -55°C to +125°C.)
DS1631/DS1631A/DS1731
AC ELECTRICAL CHARACTERISTICS(VDD = 2.7V to 5.5V; TA = -55°C to +125°C.)
NOTES:1) All voltages are referenced to GND.
2) See Figure 2 for Typical Operating Curves.
3) Specified with TOUT pin open; A0, A1, A2 = 0V or VDD; and fSCL � 2Hz.
4) Specified with temperature conversions stopped; TOUT pin open; SDA = VDD; SCL = VDD; and A0, A1,A2 = 0V or VDD.
DS1631/DS1631A/DS1731
EEPROM AC ELECTRICAL CHARACTERISTICS(VDD = 2.7V to 5.5V; TA = -55°C to +125°C.)
Figure 2. TYPICAL OPERATING CURVES
Figure 3. TIMING DIAGRAMAll timing is referenced to 0.9 x VDD and 0.1 x VDD.
REFERENCE TEMPERATURE (�C)
ERROR (
REFERENCE TEMPERATURE (�C)
DS1631/DS1631A/DS1731
Table 3. REGISTER SUMMARY
OPERATION—MEASURING TEMPERATUREThe DS1631, DS1631A, and DS1731 measure temperature using bandgap-based temperature sensors. A
delta-sigma analog-to-digital converter (ADC) converts the measured temperature to a 9-, 10-, 11-, or 12-
bit (user-selectable) digital value that is calibrated in �C; for �F applications a lookup table or conversion
routine must be used. Throughout this data sheet, the term “conversion” is used to refer to the entiretemperature measurement and ADC sequence.
The DS1631 and DS1731 always power-up in a low-power idle state, and the Start Convert T command
must be used to initiate conversions. The DS1631A always begins conversions automatically at power-
up.
The DS1631, DS1631A, and DS1731 can be programmed to perform continuous consecutive conversions(continuous-conversion mode) or to perform single conversions on command (one-shot mode). The
conversion mode is programmed through the 1SHOT bit in the configuration register as explained in the
CONFIGURATION REGISTER section of this data sheet. In continuous-conversion mode, the DS1631A
begins performing continuous conversions immediately at power-up, and the DS1631 and DS1731 begin
continuous conversions after a Start Convert T command is issued. For all three devices, consecutiveconversions continue to be performed until a Stop Convert T command is issued, at which time the device
goes into a low-power idle state. Continuous conversions can be restarted at any time using the Start
Convert T command.
In one-shot mode the DS1631A performs a single conversion at power-up, and the DS1631 and DS1731
perform a single temperature conversion when a Start Convert T command is issued. For all threedevices, when the conversion is complete the device enters a low-power idle state and remains in that
state until a single temperature conversion is again initiated by a Start Convert T command.
The resolution of the output digital temperature data is user-configurable to 9, 10, 11, or 12 bits,
corresponding to temperature increments of 0.5�C, 0.25�C, 0.125�C, and 0.0625�C, respectively. Thedefault resolution at power-up is 12 bits, and it can be changed through the R0 and R1 bits in the
configuration register. Note that the conversion time doubles for each additional bit of resolution.
DS1631/DS1631A/DS1731
provides user access to the temperature register. Bits 3 through 0 of the temperature register are
hardwired to 0. When the device is configured for 12-bit resolution, the 12 MSbs (bits 15 through 4) of
the temperature register contain temperature data. For 11-bit resolution, the 11 MSbs (bits 15 through 5)
of the temperature register contain data, and bit 4 is 0. Likewise, for 10-bit resolution, the 10 MSbs (bits15 through 6) contain data, and for 9-bit the 9 MSbs (bits 15 through 7) contain data, and all unused LSbs
contain 0s. Table 4 gives examples of 12-bit resolution output data and the corresponding temperatures.
Figure 4. TEMPERATURE, TH, AND TL REGISTER FORMATbit 15bit 14bit 13bit 12bit 11bit 10bit 9bit 8
MS Bytebit 7bit 6bit 5bit 4bit 3bit 2bit 1bit 0
LS Byte
Table 4. 12-BIT RESOLUTION TEMPERATURE/DATA RELATIONSHIP
OPERATION—THERMOSTAT FUNCTIONThe thermostat output (TOUT) is updated after every temperature conversion, based on a comparisonbetween the measured digital temperature and user-defined upper and lower thermostat trip points. TOUT
remains at the updated value until the next conversion completes. When the measured temperature meets
or exceeds the value stored in the upper trip-point register (TH), TOUT becomes active and remains active
until the measured temperature falls below the value stored in the lower trip-point register (TL) (see
Figure 5). This allows the user to program any amount of hysteresis into the output response. The activestate of TOUT is user-programmable through the polarity bit (POL) in the configuration register.
The user-defined values in the TH and TL registers (see Figure 4) must be in two’s complement format
with the MSb (bit 15) containing the sign bit (S). The TH and TL resolution is determined by the R0 and
R1 bits in the configuration register (see Table 6), so the TH and TL resolution matches the output
temperature resolution. For example, for 10-bit resolution bits 5 through 0 of the TH and TL registers readout as 0 (even if 1s are written to these bits), and the converted temperature is compared to the 10 MSbs
of TH and TL.
