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Rev. I | Page 2 of 24 TABLE OF CONTENTS
REVISION HISTORY
11/10—Rev. H to Rev. I 2/09—Rev. G to Rev. H Changes to Reading Data From the AD7416/AD7417/AD7418 Changes to Figure 22 Caption and CONVST Pin Mode 8/04—Data Sheet Changed from Rev. F to Rev. G Changes to Reading Data from the AD7416/AD7417/AD7418 7/03—Data Sheet Changed from Rev. E to Rev. F 10/02—Data Sheet Changed from Rev. D to Rev. E Edits to CONVST
Rev. I | Page 3 of 24 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 serial bus address can be selected, which allows up to eight AD7416/AD7417 devices to be connected to a single bus. The AD7417 is available in a narrow body, 0.15 inch, 16-lead, small outline package (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 HIGHLIGHTS 1. The 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 T OTI setpoint register. 2. The AD7417 offers a space-saving, 10-bit analog-to-digital solution with four external voltage input channels, an on- chip temperature sensor, an on-chip reference, and a clock oscillator. 3. 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.
Rev. I | Page 4 of 24 SPECIFICATIONS AD7417/AD7418 SPECIFICATIONS VDD = 2.7 V to 5.5 V , GND = 0 V , REFIN = 2.5 V , unless otherwise noted. Table 1. Parameter A Version B Version1 Unit Test Conditions/Comments DC ACCURACY Any channel Resolution 10 10 Bits Minimum Resolution for Which No Missing Codes Are Guaranteed 10 10 Bits Relative Accuracy2 ±1 ±1 LSB max This specification is typical for VDD of 3.6 V to 5.5 V Differential Nonlinearity2 ±1 ±1 LSB max This specification is typical for VDD of 3.6 V to 5.5 V Gain Error2 ±3 ±3 LSB max External reference ±10 ±10 LSB max Internal reference Gain Error Match2 ±0.6 ±0.6 LSB max AD7417 only Offset Error2 ±4 ±4 LSB max Offset Error Match2 ±0.7 ±0.7 LSB max AD7417 only ANALOG INPUTS Input Voltage Range VREF VREF V max 0 0 V min Input Leakage Current3 ±1 ±1 μA max Input Capacitance 10 10 pF max TEMPERATURE SENSOR1 Measurement Error Ambient Temperature 25°C ±2 ±1 °C max TMIN to TMAX ±3 ±2 °C max Temperature Resolution 1/4 1/4 °C/LSB CONVERSION RATE Track-and-Hold Acquisition Time4 400 400 ns max Source impedance < 10 Ω Conversion Time Temperature Sensor 30 30 μs max Typically 27 μs Channel 1 to Channel 4 15 15 μs max Typically 10 μs REFERENCE INPUT5,6 REFIN Input Voltage Range 2.625 2.625 V max 2.5 V + 5% 2.375 2.375 V min 2.5 V − 5% Input Impedance 40 40 kΩ min Input Capacitance 10 10 pF max ON-CHIP REFERENCE Nominal 2.5 V Reference Error6 ±25 ±25 mV max Temperature Coefficient6 80 80 ppm/°C typ DIGITAL INPUTS Input High Voltage, VIH VDD × 0.7 VDD × 0.7 V min Input Low Voltage, VIL VDD × 0.3 VDD × 0.3 V max Input Leakage Current 1 1 μA max DIGITAL OUTPUTS Output Low Voltage, VOL 0.4 0.4 V max IOL = 3 mA Output High Current 1 1 μA max VOH = 5 V
Rev. I | Page 5 of 24 Parameter A Version B Version 1 Unit Test Conditions/Comments POWER REQUIREMENTS VDD 5.5 5.5 V max For specified performance 2.7 2.7 V min IDD Logic inputs = 0 V or VDD Normal Operation 600 600 μA max Power-Down 1.5 1.5 μA max 0.7 μA typically Auto Power-Down Mode VDD = 3 V; see the Operating Modes section
10 SPS Throughput Rate 6 6 μW typ
1 kSPS Throughput Rate 60 60 μW typ 10 kSPS Throughput Rate 600 600 μW typ Power-Down 3 3 μW max Typically 0.15 μW 1 B 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 maximum and temperature sensor measurement error = ±3°C maximum. 2 See the Terminology section. 3 Refers to the input current when the part is not converting. Primarily due to reverse leakage current in the ESD protection diodes. 4 Sample tested during initial release and after any redesign or process change that may affect this parameter. 5 On-chip reference shuts down when an external reference is applied. 6 The accuracy of the temperature sensor is affected by reference tolerance.
VDD = 2.7 V to 5.5 V , GND = 0 V , REFIN = 2.5 V , unless otherwise noted. 1 For VDD = 2.7 V to 3 V, TA maximum = 85°C and temperature sensor measurement error = ±3°C maximum. 2 Sample tested during initial release and after any redesign or process change that may affect this parameter. Figure 4. Diagram for Serial Bus Timing
TA = 25°C, unless otherwise noted. and the VDD pin. Figure 5 shows how the diode should be connected. Figure 5. Diode Connection
Figure 6. AD7417 Pin Configuration (SOIC/TSSOP) Table 4. AD7417 Pin Function Descriptions 1, 16 NC No Connection. Do not connect anything to this pin. 2 SDA Digital I/O. Serial bus bidirectional data. Push-pull output. 3 SCL Digital Input. Serial bus clock. serial read operation. Open-drain output. 6 GND Ground reference for track-and-hold, comparator and capacitor DAC, and digital circuitry. writing to the configuration register of the AD7417. 11 A2 Digital Input. This is the highest programmable bit of the serial bus address. 12 A1 Digital Input. This is the middle programmable bit of the serial bus address. 13 A0 Digital Input. This is the lowest programmable bit of the serial bus address. 14 VDD Positive Supply Voltage, 2.7 V to 5.5 V.
Figure 7. AD7416 Pin Configuration (SOIC/MSOP) Figure 8. AD7418 Pin Configuration (SOIC/MSOP) Table 5. AD7416 Pin Function Descriptions 1 SDA Digital I/O. Serial bus bidirectional data. Push-pull output. 2 SCL Digital Input. Serial bus clock. 4 GND Ground reference for track-and-hold, comparator and capacitor DAC, and digital circuitry. 5 A2 Digital Input. This is the highest programmable bit of the serial bus address. 6 A1 Digital Input. This is the middle programmable bit of the serial bus address. 7 A0 Digital Input. This is the lowest programmable bit of the serial bus address. 8 VDD Positive Supply Voltage, 2.7 V to 5.5 V. Table 6. AD7418 Pin Function Descriptions 1 SDA Digital I/O. Serial bus bidirectional data. Push-pull output. 2 SCL Digital Input. Serial bus clock. 4 GND Ground reference for track-and-hold, comparator and capacitor DAC, and digital circuitry. register of the AD7418 and choosing Channel 4. 7 VDD Positive Supply Voltage, 2.7 V to 5.5 V.
Rev. I | Page 10 of 24 TERMINOLOGY Relative Accuracy Relative accuracy or endpoint nonlinearity is the maximum deviation from a straight line passing through the endpoints of the ADC transfer function. Differential Nonlinearity This is the difference between the measured and the ideal 1 LSB change between any two adjacent codes in the ADC. Offset Error This is the deviation of the first code transition (0000…000) to (0000…001) from the ideal, that is, GND + 1 LSB. Offset Error Match This is the difference in offset error between any two channels. Gain Error This is the deviation of the last code transition (1111…110) to (1111…111) from the ideal, that is, VREF − 1 LSB, after the offset error has been adjusted out. Gain Error Match This is the difference in gain error between any two channels. Track-and-Hold Acquisition Time Track-and-hold acquisition time is the time required for the output of the track-and-hold amplifier to reach its final value, within ±½ 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 A IN 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 or step input change to AIN before starting another conversion, to ensure that the part operates to specification.
Table 8. Register Addresses 10-bit twos complement format. Bit D5 to Bit D0 are unused. Table 9. Temperature Value Register to the operating temperature range of the device. Table 10. Temperature Data Format used to set the operating modes of the AD7416/AD7417/AD7418. Table 12. Bits[D7:D5] should always be set to 000 for the AD7416. Bit D4 and Bit D3 are used to set the length of the fault queue. Table 11. Configuration Register Table 12. Channel Selection Table 13. Fault Queue Settings equivalent to the nine MSBs of the temperature value register. Bit D6 to Bit D0 are unused. equivalent to the nine MSBs of the temperature value register. Table 14. T 10 MSBs store the value produced by the ADC in binary format. register with 10 MSBs containing the ADC conversion request. Table 15. ADC Value Register AD7417 and AD7418 ADC is shown in Figure 14.
Figure 14. Ideal Transfer Function Characteristic for the AD7417/AD7418 when the CONVST pin is used. Bit 6 contains the Test 1 bit. this bit to 1 disables the filters. Table 16. Config2 Register master device, for example, the processor. the AD7418 are set to 0101, and the three LSBs are all set to 0. the conversion stops and restarts after the communication.
- The master initiates data transfer by establishing a start condi-
line, SDA, while the serial clock line, SCL, remains high. to or read from the slave device.
- Data is sent over the serial bus in sequences of nine clock
tion when the clock is high may be interpreted as a stop signal.
- When all data bytes have been read or written, stop
different writes for the AD7416/AD7417/AD7418.
- Writing to the address pointer register for a subsequent read. To read data from a particular register, the address pointer register must contain the address of that register. If it does not, the correct address must be written to the address pointer register by performing a single-byte write operation, as shown in Figure 15. The write operation consists of the serial bus address followed by the address pointer byte. No data is written to any of the data registers.
- Writing a single byte of data to the configuration register, the Config2 register, or to the T OTI setpoint or THYST setpoint registers. The configuration register is an 8-bit register, so only one byte of data can be written to it. If only 8-bit temperature comparisons are required, the temperature LSB can be ignored in T OTI and THYST, and only eight bits need to be written to the TOTI setpoint and THYST setpoint registers. Writing a single byte of data to one of these registers consists of the serial bus address, the data register address written to the address pointer register, followed by the data byte
Figure 20. Operation of OTI Output (Shown Active Low) together when in active low mode. the configuration register to 1. subsequently falls again, below THYST. the maximum voltage rating of the OTI output is not exceeded. required. For most applications, a value of 10 kΩ is suitable. the fault queue counter is reset without triggering OTI.
- Address pointer pointing to temperature value register comparator mode
- T OTI = 80°C
- THYST = 75°C
- OTI active low
- Fault queue = 1 These default settings allow the AD7416/AD7417/AD7418 to be used as a standalone thermostat without any connection to a serial bus. OPERATING MODES The AD7416/AD7417/AD7418 have two possible modes of operation depending on the value of D0 in the configuration register. Mode 1 Normal operation of the AD7416/AD7417/AD7418 occurs when D0 = 0. In this active mode, a conversion takes place every 400 μs. After the conversion has taken place, the part partially powers down, consuming typically 350 μA of the current until the next conversion occurs. Two situations can arise in this mode on the request of a tempera- ture read. If a read occurs during a conversion, the conversion aborts and a new one starts on the stop/repeat start condition. The temperature value that is read is that of the previous com- pleted conversion. The next conversion typically occurs 400 μs after the new conversion has begun. If a read is called between conversions, a conversion is initiated on the stop/repeat start condition. After this conversion, the part returns to performing a conversion every 400 μs. With V DD = 3 V for each 400 μs cycle, the AD7416/AD7417/ AD7418 spend 40 μs (or 10% of the time) in conversion mode. The part spends 360 μs (or 90% of time) in partial power-down mode. Thus, the average power dissipated by the AD7416/ AD7417/AD7418 is 3 mW × 0.1 + 1 mW × 0.9 = 1.2 mW
- Figure 25 shows a system in which eight AD7416
can be connected separately to the I/O chip. Figure 25. Multiple Connection of AD7416 Devices to a Single Serial Bus
Figure 28. 16-Lead Thin Shrink Small Outline Package [TSSOP]
0.65 BSC
1.10 MAX
Figure 29. 8-Lead Mini Small Outline Package [MSOP]
Rev. I | Page 23 of 24 ORDERING GUIDE Model1 Temperature Range Temperature Error Package Description Branding Package Option AD7416AR −40°C to +125°C ±2°C 8-Lead Standard Small Outline Package (SOIC_N) R-8 AD7416AR-REEL −40°C to +125°C ±2°C 8-Lead Standard Small Outline Package (SOIC_N) R-8 AD7416AR-REEL7 −40°C to +125°C ±2°C 8-Lead Standard Small Outline Package (SOIC_N) R-8 AD7416ARZ −40°C to +125°C ±2°C 8-Lead Standard Small Outline Package (SOIC_N) R-8 AD7416ARZ-REEL −40°C to +125°C ±2°C 8-Lead Standard Small Outline Package (SOIC_N) R-8 AD7416ARZ-REEL7 −40°C to +125°C ±2°C 8-Lead Standard Small Outline Package (SOIC_N) R-8 AD7416ARM −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) C6A RM-8 AD7416ARM-REEL −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) C6A RM-8 AD7416ARM-REEL7 −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) C6A RM-8 AD7416ARMZ −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) C6A# RM-8 AD7416ARMZ-REEL −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) C6A# RM-8 AD7416ARMZ-REEL7 −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) C6A# RM-8 AD7417-WAFER Bare Die Wafer AD7417AR −40°C to +125°C ±2°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417AR-REEL −40°C to +125°C ±2°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417AR-REEL7 −40°C to +125°C ±2°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417ARZ −40°C to +125°C ±2°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417ARZ-REEL −40°C to +125°C ±2°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417ARZ-REEL7 −40°C to +125°C ±2°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417ARU −40°C to +125°C ±2°C 16-Lead Thin Shrink Small Outline Package (TSSOP) RU-16 AD7417ARU-REEL −40°C to +125°C ±2°C 16-Lead Thin Shrink Small Outline Package (TSSOP) RU-16 AD7417ARU-REEL7 −40°C to +125°C ±2°C 16-Lead Thin Shrink Small Outline Package (TSSOP) RU-16 AD7417ARUZ −40°C to +125°C ±2°C 16-Lead Thin Shrink Small Outline Package (TSSOP) RU-16 AD7417ARUZ-REEL −40°C to +125°C ±2°C 16-Lead Thin Shrink Small Outline Package (TSSOP) RU-16 AD7417ARUZ-REEL7 −40°C to +125°C ±2°C 16-Lead Thin Shrink Small Outline Package (TSSOP) RU-16 AD7417BR −40°C to +85°C ±1°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417BR-REEL −40°C to +85°C ±1°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417BR-REEL7 −40°C to +85°C ±1°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417BRZ −40°C to +85°C ±1°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417BRZ-REEL −40°C to +85°C ±1°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7417BRZ-REEL7 −40°C to +85°C ±1°C 16-Lead Standard Small Outline Package (SOIC_N) R-16 AD7418ACHIPS Die AD7418ARZ −40°C to +125°C ±2°C 8-Lead Standard Small Outline Package (SOIC_N) R-8 AD7418ARZ-REEL −40°C to +125°C ±2°C 8-Lead Standard Small Outline Package (SOIC_N) R-8 AD7418ARZ-REEL7 −40°C to +125°C ±2°C 8-Lead Standard Small Outline Package (SOIC_N) R-8 AD7418ARM −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) C7A RM-8 AD7418ARM-REEL −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) C7A RM-8 AD7418ARM-REEL7 −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) C7A RM-8 AD7418ARMZ −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) T0G RM-8 AD7418ARMZ-REEL −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) T0G RM-8 AD7418ARMZ-REEL7 −40°C to +125°C ±2°C 8-Lead Mini Small Outline Package (MSOP) T0G RM-8 EVAL-AD7416/7/8EBZ Evaluation Board 1 Z = RoHS Compliant Part.
Rev. I | Page 24 of 24 NOTES I2C refers to a communications protocol originally developed by Philips Semiconductors (Now NXP Semiconductors). ©1998–2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D01126-0-11/10(I)