Datasheet AD7416, AD7417, AD7418 (Analog Devices) - 8

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AD7416/AD7417/AD7418 Data Sheet PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS NC 1 16 NC SDA 2 15 CONVST SCL 3 14 VDD AD7417 OTI 4 13 A0 TOP VIEW REFIN 5 (Not to Scale) 12 A1 GND 6 11 A2 AIN1 7 10 AIN4
5 0
A
0
IN2 8 9 AIN3
6- 12 1 0
NC = NO CONNECT
Figure 6. AD7417 Pin Configuration (SOIC/TSSOP)
Table 4. AD7417 Pin Function Descriptions Pin No. Mnemonic Description
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. 4 OTI This pin is a logic output. The overtemperature indicator (OTI) is set if the result of a conversion on Channel 0 (temperature sensor) is greater than an 8-bit word in the TOTI setpoint register. The signal is reset at the end of a serial read operation. Open-drain output. 5 REFIN Reference Input. An external 2.5 V reference can be connected to the AD7417 at this pin. To enable the on-chip reference, the REFIN pin should be tied to GND. If an external reference is connected to the AD7417, the internal reference shuts down. 6 GND Ground reference for track-and-hold, comparator and capacitor DAC, and digital circuitry. 7 to 10 AIN1 to AIN4 Analog Input Channels. The AD7417 has four analog input channels. The input channels are single-ended with respect to GND. The input channels can convert voltage signals in the range of 0 V to VREF. A channel is selected by 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. 15 CONVST Logic Input Signal. Convert start signal. The rising edge of this signal fully powers up the part. The power-up time for the part is 4 μs. If the CONVST pulse is greater than 4 μs, the falling edge of CONVST places the track-and-hold mode into hold mode and initiates a conversion. If the pulse is less than 4 μs, an internal timer ensures that the track-and-hold does not go into hold, and conversion is not initiated until the power-up time has elapsed. The track-and-hold goes into track mode again at the end of conversion (see the Operating Modes section). Rev. J | Page 8 of 23 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAMS TABLE OF CONTENTS REVISION HISTORY PRODUCT HIGHLIGHTS SPECIFICATIONS AD7417/AD7418 SPECIFICATIONS AD7416 SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS TERMINOLOGY THEORY OF OPERATION CIRCUIT INFORMATION CONVERTER DETAILS TYPICAL CONNECTION DIAGRAM ANALOG INPUTS ON-CHIP REFERENCE TEMPERATURE MEASUREMENT INTERNAL REGISTER STRUCTURE Address Pointer Register Temperature Value Register (Address 0x00) Configuration Register (Address 0x01) THYST Setpoint Register (Address 0x02) TOTI Setpoint Register (Address 0x03) ADC Value Register (Address 0x04) ADC Transfer Function Config2 Register (Address 0x05) SERIAL BUS INTERFACE Serial Bus Address Writing to the AD7416/AD7417/AD7418 Reading Data From the AD7416/AD7417/AD7418 OTI OUTPUT FAULT QUEUE POWER-ON DEFAULTS OPERATING MODES Mode 1 Mode 2 CONVSTB START MODE CONVSTB Pin Mode APPLICATIONS INFORMATION SUPPLY DECOUPLING POWER-ON RESET MOUNTING THE AD7416/AD7417/AD7418 FAN CONTROLLER THERMOSTAT SYSTEM WITH MULTIPLE AD7416 DEVICES OUTLINE DIMENSIONS ORDERING GUIDE