Electronic Components Datasheet Search |
|
AD7112CN Datasheet(PDF) 5 Page - Analog Devices |
|
AD7112CN Datasheet(HTML) 5 Page - Analog Devices |
5 / 12 page AD7112 REV. 0 –5– CIRCUIT DESCRIPTION GENERAL CIRCUIT INFORMATION The AD7112 consists of a dual 17-bit R-2R CMOS multiplying D/A converter with extensive digital logic. Figure 1 shows a sim- plified circuit of the D/A converter section of the AD7112. The logic translates the 8-bit binary input into a 17-bit word which is used to drive the D/A converter. Figure 2 shows a typical circuit configuration for the AD7112. The transfer function for the circuit of Figure 2 is given by: VO = –VIN × 10 exp – 0.375 N 20 or VO VIN dB = – 0.375 N where 0.375 is the step size (resolution ) in dB and N is the input code in decimal for values 0 to 239. For 240 ≤ N ≤ 255 the output is zero. Table I gives the output attenuation relative to 0 dB for all possible input codes. R 2R VINA RR 2R 2R 2R 2R R RFB A OUT A AGND S1 S2 S3 S17 Figure 1. Simplified D/A Circuit of 1/2 AD7112 Figures 16 and 17 give a pictorial representation of the specified accuracy and monotonic ranges for all grades of the AD7112. High attenuation levels are specified with less accuracy than low attenuation levels. The range of monotonic behavior depends upon the attenuation step size used. To achieve monotonic op- eration over the entire 88.5 dB range, it is necessary to select in- put codes so that the attenuation step size at any point is consistent with the step size guaranteed for monotonic opera- tion at that point. OUT A AGND DAC A AD7112 DGND CS WR RFB A VIN A DAC A/DAC B VDD 15 4 3 17 5 2 1 VOUT A1 C1 SIGNAL GROUND A1: 1/2 AD712 1/2 OP-275 6 16 NOTES 1. ONLY ONE DAC IS SHOWN FOR CLARITY. 2. DATA INPUT CONNECTIONS ARE OMITTED. 3. C1 PHASE COMPENSATION (5–15pF) MAY BE REQUIRED WHEN USING HIGH SPEED AMPLIFIER. Figure 2. Typical Circuit Configuration Table I. Ideal Attenuation in dB vs. Input Code D7–D4 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111 0000 0.000 0.375 0.750 1.125 1.500 1.875 2.250 2.625 3.000 3.375 3.750 4.125 4.500 4.875 5.250 5.625 0001 6.000 6.375 6.750 7.125 7.500 7.875 8.250 8.625 9.000 9.375 9.750 10.125 10.500 10.875 11.250 11.625 0010 12.000 12.375 12.750 13.125 13.500 13.875 14.250 14.625 15.000 15.375 15.750 16.125 16.500 16.875 17.250 17.625 0011 18.000 18.375 18.750 19.125 19.500 19.875 20.250 20.625 21.000 21.375 21.750 22.125 22.500 22.875 23.250 23.625 0100 24.000 24.375 24.750 25.125 25.500 25.875 26.250 26.625 27.000 27.375 27.750 28.125 28.500 28.875 29.250 29.625 0101 30.000 30.375 30.750 31.125 31.500 31.875 32.250 32.625 33.000 33.375 33.750 34.125 34.500 34.875 35.250 35.625 0110 36.000 36.375 36.750 37.125 37.500 37.875 38.250 38.625 39.000 39.375 39.750 40.125 40.500 40.875 41.250 41.625 0111 42.000 42.375 42.750 43.125 43.500 43.875 44.250 44.625 45.000 45.375 45.750 46.125 46.500 46.875 47.250 47.625 1000 48.000 48.375 48.750 49.125 49.500 49.875 50.250 50.625 51.000 51.375 51.750 52.125 52.500 52.875 53.250 53.625 1001 54.000 54.375 54.750 55.125 55.500 55.875 56.250 56.625 57.000 57.375 57.750 58.125 58.500 58.875 59.250 59.625 1010 60.000 60.375 60.750 61.125 61.500 61.875 62.250 62.625 63.000 63.375 63.750 64.125 64.500 64.875 65.250 65.625 1011 66.000 66.375 66.750 67.125 67.500 67.875 68.250 68.625 69.000 69.375 69.750 70.125 70.500 70.875 71.250 71.625 1100 72.000 72.375 72.750 73.125 73.500 73.875 74.250 74.625 75.000 75.375 75.750 76.125 76.500 76.875 77.250 77.625 1101 78.000 78.375 78.750 79.125 79.500 79.875 80.250 80.625 81.000 81.375 81.750 82.125 82.500 82.875 83.250 83.625 1110 84.000 84.375 84.750 85.125 85.500 85.875 86.250 86.625 87.000 87.375 87.750 88.125 88.500 88.875 89.250 89.625 1111 MUTE MUTE MUTE MUTE MUTE MUTE MUTE MUTE MUTE MUTE MUTE MUTE MUTE MUTE MUTE MUTE D3–D0 |
Similar Part No. - AD7112CN |
|
Similar Description - AD7112CN |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |