Datasheet AD650 (Analog Devices) - 7

AD650 Data Sheet PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS T T V E E OUT 1 14 OFFSET NULL L L UT +IN 2 13 OFFSET NULL N O +I V NC OFFS NUL OFFS NUL –IN 3 12 +V AD650 S 3 2 1 20 19 BIBOLAR OFFSET 4 TOP VIEW 11 ANALOG GND CURRENT (Not to Scale) 4 PIN 1 18 +V –V –IN S S 5 10 DIGITAL GND INDENTFIER ONE SHOT COMPARATOR 6 9 NC 5 17 NC CAPACITOR INPUT BIPOLAR OFFSET AD650 NC 7 8 F ANALOG GND OUTPUT 6 16
010
CURRENT TOP VIEW (Not to scale) NC = NO CONNECT NC 7 15 NC
00797- Figure 2. D-14, N-14 Pin Configurations
–V 8 14 S DIGITAL GND 9 10 11 12 13 T R R O NC NC UT O UT HO T P S UT INP ACI O NE F ARAT O P CAP M
011
CO NC = NO CONNECT
00797- Figure 3. P-20 Pin Configuration
Table 2. Pin Function Descriptions Pin No. D-14, N-14 P-20 Mnemonic Description
1 2 VOUT Output of Operational Amplifier. The operational amplifier, along with CINT, is used in the integrate stage of the V to F conversion. 2 3 +IN Positive Analog Input. 3 4 –IN Negative Analog Input. 4 6 BIPOLAR OFFSET On-Chip Current Source. This can be used in conjunction with an external CURRENT resistor to remove the operational amplifier’s offset. 5 8 –VS Negative Power Supply Input. 6 9 ONE-SHOT The Capacitor, COS, is Connected to This Pin. COS determines the time period CAPACITOR for the one shot. 7 1, 5, 7, 10, 11, 15, 17 NC No Connect. 8 12 FOUTPUT Frequency Output from AD650. 9 13 COMPARATOR INPUT Input to Comparator. When the input voltage reaches −0.6 V, the one shot is triggered. 10 14 DIGITAL GND Digital Ground. 11 16 ANALOG GND Analog Ground. 12 18 +VS Positive Power Supply Input. 13, 14 19, 20 OFFSET NULL Offset Null Pins. Using an external potentiometer, the offset of the operational amplifier can be removed. Rev. E | Page 6 of 20 Document Outline Features Functional Block Diagram Product Description Product Highlights Revision History Specifications Absolute Maximum Ratings ESD Caution Pin Configurations and Function Descriptions Circuit Operation Unipolar Configuration One-Shot Timing Component Selection Bipolar V/F Unipolar V/F, Negative Input Voltage F/V Conversion High Frequency Operation Decoupling and Grounding Temperature Coefficients Nonlinearity Specification PSRR Other Circuit Considerations Applications Differential Voltage-to-Frequency Conversion Autozero Circuit Phase-Locked Loop F/V Conversion Outline Dimensions Ordering Guide