Accurate, 10-Bit Digital Temperature Sensors SOT-23 AD7414/AD7415

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Accurate, 10-Bit Digital Temperature Sensors SOT-23 AD7414/AD7415

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FEATURES 10-Bit Temperature-to-Digital Converter Temperature Range: Typical Accuracy SMBus/I2C® Compatible Serial Interface Power-Down Current Temperature Conversion Time: Space-Saving 6-Lead (AD7414) 5-Lead (AD7415) SOT-23 Packages Selectable Addressing Overtemperature Indicator (AD7414 Only) SMBus Alert Function (AD7414 Only) Versions Allow Addresses (AD7414) Versions Allow Addresses (AD7415) APPLICATIONS Hard Disk Drives Personal Computers Electronic Test Equipment Office Equipment Domestic Appliances Process Control Cellular Phones GENERAL DESCRIPTION
Accurate, 10-Bit Digital Temperature Sensors SOT-23 AD7414/AD7415
10-BIT ANALOG-DIGITAL CONVERTER CONFIGURATION REGISTER THIGH SETPOINT REGISTER TLOW SETPOINT REGISTER TEMPERATURE VALUE REGISTER BAND TEMPERATURE SENSOR
SETPOINT COMPARATOR
ALERT
SMBus/I2C INTERFACE
AD7414 AD7415
BAND TEMPERATURE SENSOR 10-BIT ANALOG-DIGITAL CONVERTER
AD7414/AD7415 complete temperature monitoring system 6-lead 5-lead SOT-23 packages. contains band temperature sensor 10-bit monitor digitize temperature reading resolution 0.25C. AD7414/AD7415 provides 2-wire serial interface that compatible with SMBus interfaces. part comes four versions, AD7414/AD7415-0, AD7414/AD7415-1, AD7414-2, AD7414-3. AD7414/AD7415-0 AD7414/AD7415-1 versions provide choice three different SMBus addresses each version. four AD7414 versions give possibility eight different addresses while AD7415 versions allow addresses used. AD7414/AD7415's supply voltage, supply current, serial interface, small package size make ideal variety applications, including personal computers, office equipment, cellular phones, domestic appliances. AD7414, on-chip registers programmed with high temperature limits, open-drain overtemperature indicator output (ALERT) that becomes active when programmed limit exceeded. Configuration register allows programming state ALERT output (active high active low). This output used interrupt SMBus alert. REV.
Information furnished Analog Devices believed accurate reliable. However, responsibility assumed Analog Devices use, infringements patents other rights third parties that result from use. license granted implication otherwise under patent patent rights Analog Devices. Trademarks registered trademarks property their respective companies.
CONFIGURATION REGISTER
TEMPERATURE VALUE REGISTER
SMBus/I2C INTERFACE
PRODUCT HIGHLIGHTS
AD7414/AD7415 on-chip temperature sensor that allows accurate measurement ambient temperature made. capable 0.5C temperature accuracy. SMBus/I2C compatible serial interface with selectable choice three addresses version AD7414/AD7415, eight address options total AD7414 total AD7415. Supply voltage Space-saving 5-lead 6-lead SOT-23 packages. 10-bit temperature reading 0.25C resolution. AD7414 overtemperature indicator that software disabled. Used interrupt SMBus alert. One-shot automatic temperature conversion rates.
Technology Way, P.O. 9106, Norwood, 02062-9106, U.S.A. Tel: 781/329-4700 www.analog.com Fax: 781/326-8703 2002 Analog Devices, Inc. rights reserved.
AD7414/AD7415-SPECIFICATIONS1
TMAX, unless otherwise noted.)
Test Conditions/Comments +40C +40C -40C +70C -40C +85C +40C -40C +85C -40C +85C
Parameter TEMPERATURE SENSOR Accuracy2
Version -0.87 +0.823 1.873
Unit Bits
Resolution Update Rate, Temperature Conversion Time POWER SUPPLIES Supply Current4 Peak Supply Current5 Supply Current Nonconverting Inactive Serial Bus6 Normal Mode Normal Mode Active Serial Bus7 Normal Mode Normal Mode Shutdown Mode DIGITAL INPUT Input High Voltage, Input Voltage, Input Current, IIN8 Input Capacitance, DIGITAL OUTPUT (OPEN-DRAIN) Output High Voltage, Output Voltage, Output High Current, Output Capacitance, COUT ALERT Output Saturation Voltage ELECTRICAL CHARACTERISTICS9, Serial Clock Period, Data Setup Time High, Data Stable after Low, Setup Time (Start Condition), High Hold Time after High (Stop Condition), Fall Time, Power-Up Time
Current during Conversion Peak Current between Conversions Supply Current with Serial Inactive. Part converting Configuration Register Supply Current with Serial Active. Part converting Configuration Register Configuration Register Typical values 0.04
Digital Inputs
IOUT Figure Figure Figure Figure Figure Figure
NOTES Temperature range follows: Version -40C +85C. Accuracy specifications apply only voltages listed under Test Conditions. Temperature Accuracy Supply section typical accuracy performance over full supply range. 100% production tested these limits. These current values used determine average power consumption different one-shot conversion rates. Average power consumption automatic conversion rate 1.25 This peak supply current required (the conversion time plus power-up time) every (the conversion rate). These current values derived issuing stop condition write read, thus preventing part from going into conversion. current derived assuming serial clock being active continuously. power-up, initial input current, typically timing measured with input filters turned meet Fast Mode specification. Switching input filters improves transfer rate negative effect behavior part. Guaranteed design. tested production. Specifications subject change without notice.
REV.
AD7414/AD7415
FUNCTION DESCRIPTIONS CONFIGURATIONS SOT-23
Mnemonic Description Logic Input. Address select input that selects three addresses AD7414/AD7415 (see Table Recommend pull-up pull-down resistor Analog Digital Ground Positive Supply Voltage, Digital I/O. Serial bidirectional data. Open-drain output. AD7414 Digital Output. Overtemperature indicator becomes active when temperature exceeds THIGH. Open-drain output. Digital Input. Serial clock.
AD7414
VIEW (Not Scale) ALERT
ALERT
MSOP
AD7414
ALERT CONNECT VIEW (Not Scale)
ABSOLUTE MAXIMUM RATINGS
-0.3 Input Voltage -0.3 Output Voltage -0.3 Input Voltage -0.3 ALERT Output Voltage -0.3 Operating Temperature Range -40C +85C Storage Temperature Range -65C +150C Junction Temperature2 150C SOT-23, Power Dissipation Thermal Impedance 240C/W Lead Temperature, Soldering Vapor Phase sec) 215C Infrared sec) 220C MSOP, Power Dissipation Thermal Impedance 206C/W Lead Temperature Soldering Vapor Phase sec) 215C Infrared sec) 220C
NOTES Stresses above those listed under Absolute Maximum Ratings cause permanent damage device. This stress rating only; functional operation device these other conditions above those indicated operational section this specification implied. Exposure absolute maximum rating conditions extended periods affect device reliability. Maximum junction temperature calculated using: TAMBMAX WMAX). Junction-to-Ambient Thermal Resistance, Maximum Power Dissipated device, AMBMAX Maximum Ambient Temperature.
SOT-23
AD7415
VIEW (Not Scale)
Table Address Selection
Part Number AD7414-0 AD7414-0 AD7414-0 AD7414-1 AD7414-1 AD7414-1 AD7414-2 AD7414-3
Float Float Float Float
Address 1001 1001 1001 1001 1001 1001 1001 1001 1001 1001 1001 1001 1001 1001
AD7415-0 AD7415-0 AD7415-0 AD7415-1 AD7415-1 AD7415-1
DATA DATA
Figure Diagram Serial Timing
REV.
AD7414/AD7415
ORDERING GUIDE
Model AD7414ART-0REEL7 AD7414ART-0REEL AD7414ART-0500RL7 AD7414ARM-0REEL7 AD7414ARM-0REEL AD7414ARM-02 AD7414ART-1REEL7 AD7414ART-1REEL AD7414ART-1500RL7 AD7414ARM-1REEL7 AD7414ARM-1REEL AD7414ARM-12 AD7414ART-2REEL7 AD7414ART-2REEL AD7414ART-3REEL7 AD7414ART-3REEL AD7415ART-0REEL7 AD7415ART-0REEL AD7415ART-0500RL7 AD7415ART-1REEL7 AD7415ART-1REEL AD7415ART-1500RL7
NOTES Available order. This model shipped tubes. Contact factory availability.
Temperature Range -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C -40C +85C
Temperature Error
Package Options RT-6 RT-6 RT-6 RM-8 RM-8 RM-8 RT-6 RT-6 RT-6 RM-8 RM-8 RM-8 RT-6 RT-6 RT-6 RT-6 RT-5 RT-5 RT-5 RT-5 RT-5 RT-5
Package Description 6-Lead SOT-23 6-Lead SOT-23 6-Lead SOT-23 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 6-Lead SOT-23 6-Lead SOT-23 6-Lead SOT-23 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 6-Lead SOT-23 6-Lead SOT-23 6-Lead SOT-23 6-Lead SOT-23 5-Lead SOT-23 5-Lead SOT-23 5-Lead SOT-23 5-Lead SOT-23 5-Lead SOT-23 5-Lead SOT-23
Branding Information CHA1 CHA1 CHA1 CHA1 CHA1 CHA1 CHB3 CHB3 CHB3 CHB3 CHB3 CHB3 CHC3 CHC3 CHD3 CHD3 CGA1 CGA1 CGA1 CGB3 CGB3 CGB3
Minimum Quantities/Reel 3,000 10,000 3,000 10,000 3,000 10,000 3,000 10,000 3,000 10,000 3,000 10,000 3,000 10,000 3,000 10,000
CAUTION (electrostatic discharge) sensitive device. Electrostatic charges high 4000 readily accumulate human body test equipment discharge without detection. Although AD7414/AD7415 features proprietary protection circuitry, permanent damage occur devices subjected high energy electrostatic discharges. Therefore, proper precautions recommended avoid performance degradation loss functionality.
WARNING!
SENSITIVE DEVICE
REV.
AD7414/AD7415
CIRCUIT INFORMATION
AD7414/AD7415 standalone digital temperature sensor. on-chip temperature sensor allows accurate measurement ambient device temperature made. 10-bit converter converts temperature measured into twos complement format storage Temperature register. converter made conventional successive-approximation converter based around capacitor DAC. serial interface SMBus compatible. AD7414/AD7415 requires power supply. temperature sensor working measurement range -40C +85C.
FUNCTIONAL DESCRIPTION
SUPPLY
ALERT
AD7414
Figure Typical Connection Diagram
Temperature measurement initiated couple methods. first uses internal clock countdown conversion performed. internal oscillator only circuit that powered between conversions, once times out, every wake-up signal sent power rest circuitry. monostable activated beginning wake-up signal ensure that sufficient time given power-up process. monostable typically takes time out. then takes typically each conversion completed. temperature value loaded into Temperature Value register ready reading interface. temperature measurement also initiated every time oneshot method used. This method requires user write One-Shot Configuration register when temperature measurement needed. Setting One-Shot will start temperature conversion directly after write operation. track-and-hold goes into hold approximately (monostable timeout) after STOP condition conversion then initiated. Typically later, conversion complete Temperature Value register loaded with temperature value. measurement modes compared with high temperature limit, stored 8-bit read/write register. This applicable only AD7414 since AD7415 does have ALERT subsequently does have overtemperature monitoring function. measurement greater than high limit, ALERT activated already been enabled Configuration register). There ways deactivate ALERT again: first when Alert Reset Configuration register write operation, second when temperature measured less than value TLOW register. This ALERT compatible with SMBus SMBALERT option. Configuration functions consist Switching between normal operation full power-down. Enabling disabling filters. Enabling disabling ALERT function. Setting ALERT polarity.
MEASUREMENT TECHNIQUE
common method measuring temperature exploit negative temperature coefficient diode, base-emitter voltage transistor, operated constant current. Unfortunately, this technique requires calibration null effect absolute value VBE, which varies from device device. technique used AD7414/AD7415 measure change when device operated different currents. This given where: Boltzmann's constant. charge electron (1.6 10-19 Coulombs). absolute temperature Kelvins. ratio currents.
DVBE
VOUT SENSING TRANSISTOR VOUT
SENSING TRANSISTOR
Figure Temperature Measurement Technique
Figure shows method AD7414/AD7415 uses measure ambient device temperature. measure DVBE, sensor (substrate transistor) switched between operating currents resulting waveform passed through chopperstabilized amplifier that performs functions amplification rectification waveform produce voltage proportional DVBE. This voltage measured give temperature output 10-bit twos complement format.
REV.
AD7414/AD7415
TEMPERATURE DATA FORMAT
temperature resolution 0.25C, which corresponds ADC. theoretically measure temperature span 255C; practical lowest value limited -40C device maximum ratings. grade measure temperature range -40C +85C. (Temperature data format shown Table II.)
Table Grade Temperature Data Format
AD7415 three internal registers shown Figure data registers Address Pointer Register.
TEMPERATURE VALUE REGISTER ADDRESS POINTER REGISTER CONFIGURATION REGISTER
Temperature -55C -50C -25C -0.25C +0.25C +10C +25C +50C +75C +100C +125C
Digital Output
0010 0100 0011 1000 1001 1100 1111 1111 0000 0000 0000 0001 0010 1000 0110 0100 1100 1000 0010 1100 1001 0000 1111 0100
SERIAL INTERFACE
Figure AD7415 Register Structure
Each data register address pointed Address Pointer register when communicating with Temperature Value register only data register that read-only.
ADDRESS POINTER REGISTER
Grade Temperature Conversion Formula: Positive Temperature Code
Negative Temperature
*DB9 removed from Code.
ADC* Code 512)
Address Pointer register 8-bit register that stores address that points four data registers AD7414 data registers AD7415. first byte every serial write operation AD7414/AD7415 address data registers, which stored Address Pointer register, selects data register which subsequent data bytes written. Only LSBs this register used select data register.
Table III. Address Pointer Register
INTERNAL REGISTER STRUCTURE
Register Select
AD7414 five internal registers shown Figure Four data registers Address Pointer register.
TEMPERATURE VALUE REGISTER
Table AD7414 Register Address
Registers Temperature Value Register (Read-Only) Configuration Register (Read/Write) THIGH Register (Read/Write) TLOW Register (Read/Write)
Table AD7415 Register Address
CONFIGURATION REGISTER ADDRESS POINTER REGISTER THIGH REGISTER
Registers Temperature Value Register (Read-Only) Configuration Register (Read/Write)
TLOW REGISTER
SERIAL INTERFACE
Figure AD7414 Register Structure
REV.
AD7414/AD7415
Table AD7414 Configuration Register Table VIII. AD7415 Configuration Register
FLTR
SHOT
TEST MODE
FLTR ALERT ALERT ALERT POLARITY RESET SHOT
TEST
MODE
TEST MODE
*Default settings power-up.
*Default settings power-up.
CONFIGURATION REGISTER (ADDRESS 01H)
Configuration register 8-bit read/write register that used operating modes AD7414/AD7415. AD7414, MSBs used operating modes; Table VII. used factory settings must have zeros written them during normal operation.
Table VII. AD7414 Configuration Register Setting
AD7415, only three bits used (D7, operating modes; Table used factory settings must have zeros written them during normal operation.
Table AD7415 Configuration Register Settings
Full Power-Down Bypass filtering Disable ALERT ALERT active ALERT active high Reset ALERT next temperature conversion will have ability activate Alert function. status stored; thus this will read. Initiate temperature conversion status stored; thus this will read.
Full Power-Down Bypass filtering Initiate temperature conversion status stored; thus this will read.
AD7414/AD7415 power-down mode temperature conversion still initiated one-shot operation. This involves write operation Configuration register setting One-Shot which will cause AD7414/AD7415 power perform single conversion, power down again. This very power efficient mode.
START MASTER
ACK. AD7414/AD7415
STOP MASTER
FRAME SERIAL ADDRESS BYTE
ACK. AD7414/AD7415 FRAME ADDRESS POINTER REGISTER BYTE
Figure Writing Address Pointer Register Select Register Subsequent Read Operation
START MASTER
ACK. AD7414/AD7415
FRAME SERIAL ADDRESS BYTE (CONTINUED)
ACK. AD7414/AD7415 FRAME ADDRESS POINTER REGISTER BYTE
(CONTINUED)
ACK. STOP AD7414/AD7415 MASTER
FRAME DATA BYTE
Figure Writing Address Pointer Register Followed Single Byte Data Selected Register
REV.
AD7414/AD7415
TEMPERATURE VALUE REGISTER (ADDRESS 00H) Table AD7414 Temperature Value Register (Second Read)
Temperature Value register 10-bit read-only register that stores temperature reading from twos complement format. reads necessary read data from this register. Table shows contents first byte read, while Table Table show contents second byte read from AD7414 AD7415, respectively. Table second byte used flag bits obtained from other internal registers. They function follows: ALERT_Flag: THIGH_Flag: state this same that ALERT pin. This flag when temperature measured goes above THIGH limit. reset when second temperature byte (Table read. temperature still greater than THIGH limit after read operation, flag will again. This flag when temperature measured goes below TLOW limit. reset when second temperature byte (Table read. temperature still less than TLOW limit after read operation, flag will again.
ALERT_ Flag
THIGH_ TLOW_ Flag Flag
Table XII. AD7415 Temperature Value Register (Second Read)
AD7414 THIGH REGISTER (Address 02h)
TLOW_Flag:
THIGH register 8-bit read/write register that stores upper limit that will activate ALERT output. Therefore value Temperature Value register greater than value THIGH register, ALERT activated (that ALERT enabled Configuration register). Since 8-bit register, temperature resolution
Table XIII. THIGH Register
full theoretical span 255C, practice temperature measurement range limited operating range device, -40C +85C grade.
Table Temperature Value Register (First Read)
AD7414 TLOW REGISTER (Address 03h)
TLOW register 8-bit read/write register that stores lower limit that will deactivate ALERT output. Therefore, value Temperature Value register less than value TLOW register, ALERT deactivated (that ALERT enabled Configuration register). Since 8-bit register, temperature resolution
START MASTER
ACK. MASTER STOP MASTER
ACK. AD7414/AD7415 FRAME SERIAL ADDRESS BYTE
FRAME SINGLE DATA BYTE FROM AD7414/AD7415
Figure Reading Single Byte Data from Selected Register
START MASTER
ACK. MASTER
ACK. AD7414/AD7415 FRAME SERIAL ADDRESS BYTE (CONTINUED)
FRAME MOST SIGNIFICANT DATA BYTE FROM AD7414/AD7415
(CONTINUED)
ACK. STOP MASTER MASTER FRAME LEAST SIGNIFICANT DATA BYTE FROM AD7414/AD7415
Figure Reading Bytes Data from Temperature Value Register
REV.
AD7414/AD7415
Table XIV. TLOW Register
number bytes data transferred over serial operation, possible read write operation because type operation determined beginning cannot subsequently changed without starting operation.
WRITING AD7414/AD7415
AD7414/AD7415 SERIAL INTERFACE
Control AD7414/AD7415 carried compatible serial bus. AD7414/AD7415 connected this slave device, under control master device, e.g., processor.
SERIAL ADDRESS
Depending register being written there different writes AD7414/AD7415.
Writing Address Pointer Register Subsequent Read
Like compatible devices, AD7414/AD7415 7-bit serial address. four MSBs this address AD7414/ AD7415 1001. AD7414/AD7415 comes four versions, AD7414/AD7415-0, AD7414/AD7415-1, AD7414-2, AD7414-3. first versions have three different addresses available, which selected either tying GND, VDD, letting float (see Table giving different addresses four versions, eight AD7414s AD7415s connected single serial bus, addresses avoid conflicts with other devices bus. serial protocol operates follows: master initiates data transfer establishing START condition, defined high transition serial data line SDA, while serial clock line remains high. This indicates that address/data stream will follow. slave peripherals connected serial respond START condition shift next eight bits, consisting 7-bit address (MSB first) plus bit, which determines direction data transfer, i.e. whether data will written read from slave device. peripheral whose address corresponds transmitted address responds pulling data line during period before ninth clock pulse, known Acknowledge bit. other devices remain idle while selected device waits data read from written master will write slave device. master will read from slave device. Data sent over serial sequences nine clock pulses, eight bits data followed Acknowledge from receiver data. Transitions data line must occur during period clock signal remain stable during high period, since high transition when clock high interpreted STOP signal. When data bytes have been read written, stop conditions established. WRITE mode, master will pull data line high during 10th clock pulse assert STOP condition. READ mode, master device will pull data line high during period before ninth clock pulse. This known Acknowledge. master will then take data line during period before 10th clock pulse, then high during 10th clock pulse assert STOP condition.
order read data from particular register, Address Pointer register must contain address that register. does not, correct address must written Address Pointer register performing single-byte write operation, shown Figure write operation consists serial address followed address pointer byte. data written data registers. read operation then performed read register.
Writing Single Byte Data Configuration Register, THIGH Register, TLOW Register
three registers 8-bit registers only byte data written each register. Writing single byte data these registers consists serial address, Data register address written Address Pointer register, followed data byte written selected data register. This illustrated Figure
READING DATA FROM AD7414/AD7415
Reading data from AD7414/AD7415 2-byte operation. Reading back contents Configuration register, THIGH register, TLOW register single-byte read operation, shown Figure register address previously single-byte write operation Address Pointer register. Once register address been number reads subsequently done from that register without having write Address Pointer register again. read from another register, Address Pointer register will have written again relevant register address. Reading data from Temperature Value register 2-byte operation, shown Figure same rules apply 2-byte read single-byte read.
SMBus ALERT
AD7414 ALERT output SMBus interrupt line devices that want trade their ability master extra pin. AD7414 slave-only device uses SMBus ALERT signal host device that wants talk. SMBus ALERT AD7414 used overtemperature indicator. ALERT open-drain configuration that allows ALERT outputs several AD7414s wired-AND together when ALERT active low. Configuration register active polarity ALERT output. power-up default active low. ALERT function disabled enabled setting Configuration register respectively.
REV.
AD7414/AD7415
host device process ALERT interrupt simultaneously access SMBus ALERT devices through alert response address. Only device that pulled ALERT will acknowledge (Alert Response Address). more than device pulls ALERT low, highest priority (lowest address) device will communication rights standard arbitration during slave address transfer. ALERT output becomes active when value Temperature Value register exceeds value THIGH register. reset when write operation Configuration register sets when temperature falls below value stored TLOW register. ALERT output requires external pull-up resistor. This connected voltage different from provided maximum voltage rating ALERT output exceeded. value pull-up resistor depends application, should large possible avoid excessive sink currents ALERT output, which heat chip affect temperature reading.
POWER-ON DEFAULTS
When temperature measurement required, write operation performed power part into one-shot mode (setting Configuration register power-up takes approximately part then performs conversion returned full power-down. temperature value read full power-down mode since serial interface still powered
POWER THROUGHPUT
modes operation AD7414/AD7415 will produce different power versus throughput performances. Mode sleep mode part achieves optimum power performance.
Mode
AD7414/AD7415 always powers with following defaults: Address Pointer register pointing Temperature Value register. THIGH register loaded with Hex. TLOW register loaded with Hex. Configuration register loaded with Hex. Note that AD7415 does have THIGH TLOW registers.
OPERATING MODES Mode
this mode, continuous conversions performed rate approximately every Figure shows times currents involved with this mode operation supply. current consumption part when converting typically quiescent current typically. conversion time plus power-up time typically contributes 199.3 overall power dissipation following way:
199.3
contribution total power dissipated remaining time 939.96
(799.971 199.3
199.3 939.96 940.16
1.1mA
Thus total power dissipated during each cycle
This power-on default mode AD7414/AD7415. this mode, AD7414/AD7415 does temperature conversion every then partially powers down until next conversion occurs. one-shot operation (setting Configuration register performed between automatic conversions, conversion initiated right after write operation. After this conversion, part returns performing conversion every Depending where serial port access occurs during conversion, that conversion might might aborted. conversion completed before part recognizes serial port access, Temperature register will updated with conversion. conversion completed after part recognizes serial port access, internal logic will prevent Temperature register from being updated since corrupt data could read. temperature conversion start anytime during serial port access (other than one-shot operation), result that conversion will only loaded into Temperature register serial port access active conversion.
Mode Mode
800ms TIME
Figure Mode Power Dissipation
this mode, part totally powered down. circuitry except serial interface switched off. most power efficient operating this mode one-shot method. Write Configuration register one-shot part will power approximately then perform conversion. Once conversion finished, device will power down again until Configuration register one-shot Figure shows same timing Figure mode one-shot initiated every take voltage supply work power dissipation following way. current consumption part when converting typically quiescent current typically. conversion time plus power-up time typically contributes 199.3 overall power dissipation following way:
only other mode which AD7414/AD7415 operates full power-down mode. This mode usually used when temperature measurements required very slow rate. power consumption part greatly reduced this mode writing part full power-down. Full power-down initiated right after Configuration register
199.3
contribution total power dissipated remaining time
(799.971
199.3
Thus total power dissipated during each cycle
-10-
REV.
AD7414/AD7415
1.1mA
TEMPERATURE ERROR
800nA 800ms TIME
Figure Mode Power Dissipation
MOUNTING AD7414/AD7415
AD7414/AD7415 used surface temperature sensing applications. device cemented surface with thermally conductive adhesive, temperature will within about 0.1C surface temperature, thanks device's power consumption. Care should taken insulate back leads device from ambient temperature different from surface temperature being measured. ground provides best thermal path die, temperature will close that printed circuit ground track. Care should taken ensure that this good thermal contact with surface being measured. with AD7414/AD7415 associated wiring circuits must kept free from moisture prevent leakage corrosion, particularly cold conditions where condensation more likely occur. Water-resistant varnishes conformal coatings used protection. small size AD7414/ AD7415 packages allows them mounted inside sealed metal probes, which provide safe environment device. AD7414/AD7415 should least decoupled with ceramic capacitor between GND. This particularly important AD7414/AD7415 mounted remote from power supply.
TEMPERATURE ACCURACY SUPPLY SUPPLY DECOUPLING
SUPPLY VOLTAGE
Figure Typical Temperature Error Supply Part
TYPICAL TEMPERATURE ERROR GRAPH
Figure shows typical temperature error plots device with
TEMPERATURE ERROR
5.5V 3.3V
TEMPERATURE
temperature accuracy specifications guaranteed voltage supplies only. Figure gives typical performance characteristics large sample parts over full voltage range Figure gives typical performance characteristics part over full voltage range
TEMPERATURE ERROR
Figure Typical Temperature Error
Figure shows histogram temperature error ambient temperature (40C) over approximately 6,000 units. Figure shows that over AD7414/AD7415 devices tested have temperature error within 0.3C.
AMBIENT TEMPERATURE
NUMBER UNITS
1.08
0.81
0.54
0.27
0.27
0.54
0.81
1.08
SUPPLY VOLTAGE
TEMPERATURE ERROR
Figure Typical Temperature Error Supply Large Sample Parts
Figure Ambient Temperature Error
REV.
-11-
AD7414/AD7415
OUTLINE DIMENSIONS 6-Lead Plastic Surface-Mount Package [SOT-23] (RT-6)
Dimensions shown millimeters
2.90
8-Lead MSOP Package [MSOP] (RM-8)
Dimensions shown millimeters
3.00
1.60
2.80
3.00
4.90
0.95 1.30 1.15 0.90 1.90
0.65 0.15 0.00 1.10 0.80 0.40
1.45
0.22 0.08 0.60 0.45 0.30
0.10
0.50 0.30
SEATING PLANE
0.38 0.22 COPLANARITY 0.10
0.23 0.08 SEATING PLANE
COMPLIANT JEDEC STANDARDS MO-187AA
COMPLIANT JEDEC STANDARDS MO-178AB
5-Lead Plastic Surface-Mount Package [SOT-23] (RT-5)
Dimensions shown millimeters
2.90
1.60
2.80
0.95 1.30 1.15 0.90 1.90
1.45
0.15
0.50 0.30
SEATING PLANE
0.22 0.08
0.60 0.45 0.30
COMPLIANT JEDEC STANDARDS MO-178AA
Revision History
Location 11/02-Data Sheet changed from REV. REV. Page
Changes ABSOLUTE MAXIMUM RATINGS
10/02-Data Sheet changed from REV. REV.
Changes SPECIFICATIONS Changes FUNCTION DESCRIPTIONS Changes ABSOLUTE MAXIMUM RATINGS ORDERING GUIDE updated Change Figure Added TYPICAL TEMPERATURE ERROR GRAPH section Added Figure OUTLINE DIMENSIONS updated -12- REV.
PRINTED U.S.A.
C02463-0-11/02(B)

Accurate, 10-Bit Digital Temperature Sensors SOT-23 AD7414/AD7415

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