AD7417AR-REEL7 ,Temperature Sensor: 4-Channel, 10-Bit ADC with on-Chip Temperature to Digital Converter, I2C, ±1°C AccuracySPECIFICATIONS DD INParameter Min Typ Max Unit Test Conditions/CommentsTEMPERATURE SENSOR AND ADCAc ..
AD7417ARU ,10-Bit Digital Temperature Sensor (AD7416) and Single/Four-Channel ADC (AD7417/AD7418)SPECIFICATIONS (V = +2.7 V to +5.5 V, GND = 0 V, REF = +2.5 V, unless otherwise noted)DD INParamete ..
AD7417ARU-REEL ,Temperature Sensor: 4-Channel, 10-Bit ADC with on-Chip Temperature to Digital Converter, I2C, ±1°C AccuracyCHARACTERISTICS AD7416/AD7417/AD7418Serial Clock Period, t 2.5 µs See Figure 11Data In Setup Time t ..
AD7417ARU-REEL7 ,Temperature Sensor: 4-Channel, 10-Bit ADC with on-Chip Temperature to Digital Converter, I2C, ±1°C AccuracyFEATURES FUNCTIONAL BLOCK DIAGRAMS10-Bit ADC with 15 s and 30 s Conversion TimesSingle and Four S ..
AD7417ARUZ ,Temperature Sensor: 4-Channel, 10-Bit ADC with on-Chip Temperature to Digital Converter, I2C, ±1°C AccuracyGENERAL DESCRIPTIONOVERTEMP REG B A > B OTIThe AD7417 and AD7418 are 10-bit, 4-channel and single-A ..
AD7417ARUZ-REEL , 10-Bit Digital Temperature Sensor (AD7416) and Four Single-Channel ADCs
ADF4154BRU ,Fractional-N Frequency SynthesizerCHARACTERISTICS See Figure 17 for input circuit. 110/250 MHz min/max For f < 10 MHz, use a dc-cou ..
ADF4154BRUZ ,Fractional-N Frequency SynthesizerGENERAL DESCRIPTION RF bandwidth 500 MHz to 4 GHz The ADF4154 is a fractional-N frequency synthesiz ..
ADF4154BRUZ-RL7 ,Fractional-N Frequency SynthesizerAPPLICATIONS A key feature of the ADF4154 is the fast-lock mode with a built-CATV equipment in time ..
ADF4193BCPZ-RL , Low Phase Noise, Fast Settling PLL Frequency Synthesizer
ADF4206BRU ,Dual RF PLL Frequency SynthesizersCHARACTERISTICSREFIN Input Frequency 5/40 5/40 MHz min/max For f < 5 MHz Use Square Wave 0 to VDD4R ..
ADF4212BRU ,Dual, Integer-N 0.5 GHz/3.0 GHz PLLCHARACTERISTICS See Figure 2 for Input Circuit.REFIN Input Frequency 0/115 0/115 MHz min/max For F ..
AD7417AR-REEL7-AD7417ARU-REEL-AD7417ARU-REEL7-AD7417ARUZ-AD7418AR-REEL
Temperature Sensor: Temperature to Digital Converter, I2C, 10-Bit Resolution, -40°C to +125°C, ±2°C ...
REV.G
10-Bit Digital Temperature Sensor (AD7416) and
Four Single-Channel ADCs (AD7417/AD7418)
FEATURES
10-Bit ADC with 15 �s and 30 �s Conversion Times
Single and Four Single-Ended Analog Input Channels
On-Chip Temperature Sensor: –40�C to +125�C
On-Chip Track-and-Hold
Overtemperature Indicator
Automatic Power-Down at the End of a Conversion
Wide Operating Supply Range: 2.7 V to 5.5 V2C® Compatible Serial Interface
Selectable Serial Bus Address Allows Connection of up
to Eight AD7416/AD7417s to a Single Bus
AD7416 Is a Superior Replacement for LM75
APPLICATIONS
Data Acquisition with Ambient Temperature Monitoring
Industrial Process Control
Automotive
Battery-Charging Applications
Personal Computers
FUNCTIONAL BLOCK DIAGRAMS
REFINVDD
OTI
SCL
SDAA1A0CONVST
AIN1
AIN2
AIN3
AIN4NCGND
NC = NO CONNECT
VDD
OTI
SCL
SDA
AIN1
GND
REFIN
CONVST
GENERAL DESCRIPTIONThe AD7417 and AD7418 are 10-bit, 4-channel and single-
channel ADCs with an on-chip temperature sensor that
can operate from a single 2.7 V to 5.5 V power supply. The
devices contain a 15 µs successive approximation converter, a
5-channel multiplexer, a temperature sensor, a clock oscilla-
tor, a track-and-hold, and a reference (2.5 V). The AD7416
is a temperature-monitoring only device in an 8-lead package.
The temperature sensor on the parts can be accessed via multi-
plexer Channel 0. When Channel 0 is selected and a conversion
is initiated, the resulting ADC code at the end of the conversion
gives a measurement of the ambient temperature (±1°C @ 25°C).
On-chip registers can be programmed with high and low tem-
perature limits, and an open-drain overtemperature indicator
(OTI) output is provided, which becomes active when a pro-
grammed limit is exceeded.
A configuration register allows programming of the sense of the
OTI output (active high or active low) and its operating mode
(comparator or interrupt). A programmable fault queue counter
allows the number of out-of-limit measurements that must occur
before triggering the OTI output to be set to prevent spurious
triggering of the OTI output in noisy environments.
(continued on page 7)
AD7416/AD7417/AD7418
(VDD = 2.7 V to 5.5 V, GND = 0 V, REFIN = 2.5 V, unless otherwise noted.)DIGITAL INPUTS
AD7417/AD7418–SPECIFICATIONS
AD7416/AD7417/AD7418NOTESB Version applies to AD7417 only with temperature range of –40°C to +85°C. A Version temperature range is –40°C to +125°C. For VDD = 2.7 V, TA = 85°C max
and temperature sensor measurement error = ±3°C.See Terminology.Refers to the input current when the part is not converting. Primarily due to reverse leakage current in the ESD protection diodes.Sample tested during initial release and after any redesign or process change that may affect this parameter.On-chip reference shuts down when external reference is applied.The accuracy of the temperature sensor is affected by reference tolerance. The relationship between the two is explained in the Temperature Sensor section.
Specifications subject to change without notice.
AD7416–SPECIFICATIONS(VDD = 2.7 V to 5.5 V, GND = 0 V, REFIN = 2.5 V, unless otherwise noted.)DIGITAL INPUTS
AC ELECTRICAL CHARACTERISTICS
NOTESFor VDD = 2.7 V to 3 V, TA max = 85°C and accuracy = ±3°C.Sample tested during initial release and after any redesign or process change that may affect this parameter.
Specifications subject to change without notice.
AD7416/AD7417/AD7418
AD7417 PIN FUNCTION DESCRIPTION6GND
AD7417 PIN CONFIGURATION
SOIC/TSSOP
AD7416 PIN FUNCTION DESCRIPTION4GND
5A2Digital Input. The highest programmable bit of the serial bus address.
6A1Digital Input. The middle programmable bit of the serial bus address.
7A0Digital Input. The lowest programmable bit of the serial bus address.
AD7418 PIN FUNCTION DESCRIPTION4GND
5AIN
AD7416 PIN CONFIGURATION
SOIC/MSOP
AD7418 PIN CONFIGURATION
SOIC/MSOP
AD7416/AD7417/AD7418
ABSOLUTE MAXIMUM RATINGS1(TA = 25°C, unless otherwise noted.)
VDD to AGND . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to +7V
VDD to DGND . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to +7V
Analog Input Voltage to AGND
AIN1 to AIN4 . . . . . . . . . . . . . . . . . . . –0.3 V to VDD + 0.3 V
Reference Input Voltage to AGND2 . . –0.3 V to VDD + 0.3V
Digital Input Voltage to DGND . . . . . –0.3 V to VDD + 0.3 V
Digital Output Voltage to DGND . . . . –0.3 V to VDD + 0.3 V
Operating Temperature Range
A Version . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to +125°C
B Version . . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to +85°C
Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C
TSSOP, Power Dissipation . . . . . . . . . . . . . . . . . . . . 450 mW
�JA Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 120°C/W
Lead Temperature, Soldering . . . . . . . . . . . . . . . . . .260°C
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . .215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . .220°C
16-Lead SOIC Package, Power Dissipation . . . . . . . . 450 mW
�JA Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 100°C/W
Lead Temperature, Soldering
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . 215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C
8-Lead SOIC Package, Power Dissipation . . . . . . . . . 450 mW
�JA Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 157°C/W
Lead Temperature, Soldering
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . 215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C
MSOP Package, Power Dissipation . . . . . . . . . . . . . . 450 mW
�JA Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 206°C/W
Lead Temperature, Soldering
Vapor Phase (60 sec) . . . . . . . . . . . . . . . . . . . . . . . 215°C
Infrared (15 sec) . . . . . . . . . . . . . . . . . . . . . . . . . . . 220°C
NOTESStresses above those listed under Absolute Maximum Ratings may cause perma-
nent damage to the device. This is a stress rating only; functional operation of the
device at these or any other conditions above those listed in the operational
sections of this specification is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability.If the reference input voltage is likely to exceed VDD by more than 0.3 V (e.g.,
during power-up) and the reference is capable of supplying 30 mA or more, it is
recommended to use a clamping diode between the REFIN pin and VDD pin. The
diagram below shows how the diode should be connected.
CAUTIONESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000V readily
accumulate on the human body and test equipment and can discharge without detection. Although the
AD7416/AD7417/AD7418 features proprietary ESD protection circuitry, permanent damage may
occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions
are recommended to avoid performance degradation or loss of functionality.
ORDERING GUIDEAD7416AR-REEL
AD7416AR-REEL7
AD7416ARZ*
AD7416ARZ-REEL*
AD7416ARZ-REEL7*
AD7416ARM
AD7416ARM-REEL
AD7416ARM-REEL7
AD7416ARMZ*
AD7416ARMZ-REEL*
AD7416ARMZ-REEL7*
AD7417ACHIPS
AD7417AR
AD7417AR-REEL
AD7417AR-REEL7
AD7417ARU
AD7417ARU-REEL
AD7417ARU-REEL7
AD7417BR
AD7417BR-REEL
AD7417BR-REEL7
AD7418ACHIPS
AD7418AR
AD7418AR-REEL
AD7418AR-REEL7
AD7418ARM
AD7418ARM-REEL
AD7418ARM-REEL7
AD7418ARUZ*
AD7418ARUZ-REEL*
AD7418ARUZ-REEL7*
EVAL-AD7416/AD7417/
*Pb-Free Part
AD7416/AD7417/AD7418(continued from page 1)
An I2C compatible serial interface allows the AD7416/AD7417/
AD7418 registers to be written to and read back. The three LSBs
of the AD7416/AD7417’s serial bus address can be selected,
which allows up to eight AD7416/AD7417s to be connected to
a single bus.
The AD7417 is available in a narrow body, 0.15'', 16-lead, small
outline IC (SOIC) and in a 16-lead, thin shrink, small outline
package (TSSOP). The AD7416 and AD7418 are available in
8-lead SOIC and MSOP packages.
PRODUCT HIGHLIGHTSThe AD7416/AD7417/AD7418 have an on-chip temperature
sensor that allows an accurate measurement of the ambient
temperature (±1°C @ 25°C, ±2°C overtemperature) to be
made. The measurable temperature range is –40°C to +125°C.
An overtemperature indicator is implemented by carrying
out a digital comparison of the ADC code for Channel 0
(temperature sensor) with the contents of the on-chip over-
temperature register.The AD7417 offers a space-saving 10-bit A/D solution with
four external voltage input channels, an on-chip temperature
sensor, an on-chip reference, and clock oscillator.The automatic power-down feature enables the AD7416/
AD7417/AD7418 to achieve superior power performance. At
slower throughput rates, the part can be programmed to
operate in a low power shutdown mode, allowing further
savings in power consumption.
TERMINOLOGY
Relative AccuracyRelative accuracy or endpoint nonlinearity is the maximum
deviation from a straight line passing through the endpoints of
the ADC transfer function.
Differential NonlinearityThis is the difference between the measured and the ideal 1LSB
change between any two adjacent codes in the ADC.
Offset ErrorThis is the deviation of the first code transition (0000 . . . 000)
to (0000 . . . 001) from the ideal, i.e., GND + 1 LSB.
Offset Error MatchThis is the difference in offset error between any two channels.
Gain ErrorThis is the deviation of the last code transition (1111 . . . 110)
to (1111 . . . 111) from the ideal, i.e., VREF – 1 LSB, after the
offset error has been adjusted out.
Gain Error MatchThis is the difference in gain error between any two channels.
Track-and-Hold Acquisition TimeTrack-and-hold acquisition time is the time required for the
output of the track-and-hold amplifier to reach its final value,
within ±1/2 LSB, after the end of conversion (the point at which
the track-and-hold returns to track mode). It also applies to
situations where a change in the selected input channel takes
place or where there is a step input change on the input voltage
applied to the selected AIN input of the AD7417 or AD7418. It
means that the user must wait for the duration of the track-and-
hold acquisition time after the end of conversion or after a channel
change/step input change to AIN before starting another conver-
sion, to ensure that the part operates to specification.
CIRCUIT INFORMATIONThe AD7417 and AD7418 are single-channel and four-channel,
15 µs conversion time, 10-bit ADCs with on-chip temperature
sensor, reference, and serial interface logic functions on a single
chip. The AD7416 has no analog input channel and is intended
for temperature measurement only. The ADC section consists
of a conventional successive approximation converter based
around a capacitor DAC. The AD7416, AD7417, and AD7418
are capable of running on a 2.7 V to 5.5 V power supply, and
the AD7417 and AD7418 accept an analog input range of 0 V
to +VREF. The on-chip temperature sensor allows an accurate
measurement of the ambient device temperature to be made.
The working measurement range of the temperature sensor is
–40°C to +125°C. The parts require a 2.5 V reference that can
be provided from the part’s own internal reference or from an
external reference source.
CONVERTER DETAILSConversion is initiated on the AD7417/AD7418 by pulsing the
CONVST input. The conversion clock for the part is internally
generated so no external clock is required except when reading
from and writing to the serial port. The on-chip track-and-hold
goes from track to hold mode and the conversion sequence is
started on the falling edge of the CONVST signal. A conversion
is also initiated in the automatic conversion mode every time a
read or write operation to the AD7416/AD7417/AD7418 takes
place. In this case, the internal clock oscillator (which runs the
automatic conversion sequence) is restarted at the end of the
read or write operation. The track-and-hold goes into hold
approximately 3 µs after the read or write operation is complete
and a conversion is then initiated. The result of the conversion
is available either 15 µs or 30 µs later, depending on whether an
analog input channel or the temperature sensor is selected. The
track-and-hold acquisition time of the AD7417/AD7418 is 400 ns.
A temperature measurement is made by selecting the Channel 0
of the on-chip mux and carrying out a conversion on this channel.
A conversion on Channel 0 takes 30 µs to complete. Tempera-
ture measurement is explained in the Temperature Measurement
section of this data sheet.
The on-chip reference is not available to the user, but REFIN
can be overdriven by an external reference source (2.5 V only).
All unused analog inputs should be tied to a voltage within the
nominal analog input range to avoid noise pickup. For mini-
mum power consumption, the unused analog inputs should be
tied to GND.
TYPICAL CONNECTION DIAGRAMFigure 2 shows a typical connection diagram for the AD7417.
Using the A0, A1, and A2 pins allows the user to select from up
to eight AD7417s on the same serial bus, if desired. An external
2.5 V reference can be connected at the REFIN pin. If an exter-
nal reference is used, a 10 µF capacitor should be connected
between REFIN and GND. SDA and SCL form the 2-wire I2C
compatible interface. For applications where power consump-
tion is of concern, the automatic power-down at the end of a
conversion should be used to improve power performance. See
Operating Modes section of this data sheet.
Figure 2. Typical Connection Diagram
ANALOG INPUTSFigure 3 shows an equivalent circuit of the analog input struc-
ture of the AD7417 and AD7418. The two diodes, D1 and D2,
provide ESD protection for the analog inputs. Care must be
taken to ensure that the analog input signal never exceeds the
supply rails by more than 200 mV. This will cause these diodes
to become forward-biased and start conducting current into the
substrate. The maximum current these diodes can conduct
without causing irreversible damage to the part is 20 mA. The
capacitor C2 in Figure 3 is typically about 4 pF and can prima-
rily be attributed to pin capacitance. The resistor R1 is a lumped
component made up of the on resistance of a multiplexer and a
switch. This resistor is typically about 1 kΩ. The capacitor C1 is
the ADC sampling capacitor and has a capacitance of 3 pF.
Figure 3. Equivalent Analog Input Circuit
ON-CHIP REFERENCEstart of the conversion phase and is powered down at the end of
the conversion. The on-chip reference is selected by connecting
the REFIN pin to analog ground. This causes SW1 (see Figure 4)
to open and the reference amplifier to power up during a conver-
sion. Therefore, the on-chip reference is not available externally.
An external 2.5 V reference can be connected to the REFIN pin.
This has the effect of shutting down the on-chip reference circuitry.
Figure 4. On-Chip Reference
TEMPERATURE MEASUREMENTA common method of measuring temperature is to exploit the
negative temperature coefficient of a diode, or the base-emitter
voltage of a transistor, operated at a constant current. Unfortu-
nately, this technique requires calibration to null out the effect
of the absolute value of VBE, which varies from device to device.
The technique used in the AD7416/AD7417/AD7418 is to
measure the current change in VBE when the device is operated
at two different currents.
This is given by
where:
K is Boltzmann’s constant.
q is the charge on the electron (1.6 × 10-19 Coulombs).
T is the absolute temperature in Kelvins.
N is the ratio of the two currents.
Figure 5. Temperature Measurement Technique
AD7416/AD7417/AD7418
ADDRESS POINTER REGISTERThe Address Pointer Register is an 8-bit register that stores an
address that points to one of the six data registers. The first data
byte of every serial write operation to the AD7416/AD7417/
AD7418 is the address of one of the data registers, which is
stored in the Address Pointer Register, and selects the data
register to which subsequent data bytes are written. Only the
three LSBs of this register are used to select a data register.
Table I. Address Pointer Register*P3 to P7 must be set to 0.
Table II. Register Addresses
TEMPERATURE VALUE REGISTER (ADDRESS 00h)The Temperature Value Register is a 16-bit, read-only register
whose 10 MSBs store the temperature reading from the ADC in
10-bit twos complement format. Bits 5 to 0 are unused.
Table III. Temperature Value RegisterThe temperature data format is shown in Table IV. This shows
the full theoretical range of the ADC from –128°C to +127°C,
but in practice, the temperature measurement range is limited
to the operating temperature range of the device.
Table IV. Temperature Data FormatFigure 5 shows the method the AD7416/AD7417/AD7418 uses
to measure the device temperature. To measure �VBE, the sen-
sor (substrate transistor) is switched between operating currents
of I and N × I. The resulting waveform is passed through a
chopper-stabilized amplifier that performs the functions of
amplification and rectification of the waveform to produce a dc
voltage proportional to �VBE.
This voltage is measured by the ADC to give a temperature
output in 10-bit twos complement form.
The temperature resolution of the ADC is 0.25°C, which corre-
sponds to 1 LSB of the ADC. The ADC can theoretically measure
a temperature span of 255°C; the guaranteed temperature range
is –40°C to +125°C. The result of the conversion is stored in
the Temperature Value Register (00h) as a 16-bit word. The
10 MSBs of this word store the temperature measurement (see
Table III and Table IV).
The temperature conversion formula using the 10 MSBs of the
Temperature Value Register is
1. Positive Temperature = ADC Code/4
2. Negative Temperature = (ADC Code* – 512)/4
*MSB is removed from the ADC Code.
INTERNAL REGISTER STRUCTUREThe AD7417/AD7418 has seven internal registers, as shown in
Figure 6. Six of these are data registers and one is an Address
Pointer Register. The AD7416 has five internal registers (the
ADC and Config2 Registers are not applicable to the AD7416).
Figure 6. AD7417/AD7418 Register Structure
