AD5228 Analog Devices, Inc., AD5228 Datasheet
AD5228
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AD5228 Summary of contents
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... When the button is pressed briefly (no longer than 0.6 s), the resistance of the AD5228 changes by one step. When the button is held continuously for more than a second, the device activates the autoscan mode and changes four resistance steps per second. ...
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... AD5228 TABLE OF CONTENTS Electrical Characteristics ................................................................. 3 Interface Timing Diagrams ......................................................... 4 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. 6 Typical Performance Characteristics ............................................. 7 Theory of Operation ...................................................................... 11 Programming the Digital Potentiometers............................... 12 Controlling Inputs ...................................................................... 13 Terminal Voltage Operation Range.......................................... 13 REVISION HISTORY Revision 0: Initial Version Power-Up and Power-Down Sequences.................................. 14 Layout and Power Supply Biasing ...
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... DD_STBY DD_ACT DISS DD PSSR ± 10% DD Rev Page AD5228 < +105°C, unless otherwise noted Min Typ Max Unit −0.5 ±0.05 +0.5 LSB −0.5 ±0.1 +0.5 LSB −20 + ppm/°C ...
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... The debouncer keeps monitoring the logic-low level once PU is connected to ground. Once the signal lasts longer than 11 ms, the debouncer assumes the last 12 bounce is met and allows the AD5228 to increment by one step. If the PU signal remains at low and reaches t characteristics apply to PD operation. ...
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... Exposure to absolute −40°C to +105°C maximum rating conditions for extended periods may affect 150°C device reliability. −65°C to +150°C 245°C 230°C/W Rev Page AD5228 ...
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... Resistor Terminal B. GND ≤ PRE Power-On Preset. Output = midscale if PRE = GND; output = zero scale if PRE = V No pull-up resistor is needed Positive Power Supply PRE 2 7 AD5228 GND Figure 6. SOT-23-8 Pin Configuration ≤ ≤ ≤ ...
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... 2.7V 5. CODE (Decimal) Figure 11. INL vs. Code vs. Supply Voltages CODE (Decimal) Figure 12. INL vs. Code AD5228 –40°C +25°C +85°C +105° 25° –40°C +25°C +85°C +105° ...
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... AD5228 0.10 0.08 0.06 0.04 5.5V 0.02 0 –0.02 –0.04 –0.06 –0.08 –0. CODE (Decimal) Figure 13. DNL vs. Code vs. Supply Voltages 0.10 0.08 0.06 0.04 0.02 0 –0.02 –0.04 –0.06 –0.08 –0. CODE (Decimal) Figure 14. DNL vs. Code –0.50 –0.55 –0.60 –0. 5.5V DD –0.70 –0. 2.7V DD –0.80 –0.85 – ...
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... DD A – –12 –18 –24 –30 –36 –42 –48 – START 1 000.000Hz Figure 24. Gain vs. Frequency vs. Code, R Rev Page AD5228 /DIV MARKER 469 390.941Hz 6.0dB MAG (A/R) –8.966dB T = 25° 5. 50mV rms A 16 STEPS 8 STEPS 4 STEPS 2 STEPS ...
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... AD5228 0 STEP = MIDSCALE, V – ± 10% p –40 –60 100 1k 10k FREQUENCY (Hz) Figure 25. PSRR ∆ : 8.32ms @: 8.24ms @: 378mV 1 2 CH1 5.00V CH2 100mV M2.00ms T 3.92000ms Figure 26. Basic Increment 1 2 CH1 5.00V CH2 100mV M2.00ms T 59.8000ms Figure 27. Repetitive Increment ...
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... THEORY OF OPERATION The AD5228 is a 32-position manual up/down digitally con- trolled potentiometer with selectable power-on preset. The AD5228 presets to midscale when the PRE pin is tied to ground and to zero-scale when PRE is tied not allowed. The step-up and step-down operations require the activation of the PU (push-up) and PD (push-down) pins. ...
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... AD5228 If the PU button is held for longer than 1 second, continuously holding it activates autoscan mode such that the AD5228 increments by four R steps per second (see Figure 3). WB Whenever the maximum reached incrementing regardless of the state of the PU pin. Any continu- ous holding of the PU pin to logic-low simply elevates the supply current ...
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... All PU and PD inputs are protected with a Zener ESD structure as shown in Figure 37. PU and PD pins are usually connected to pushbutton tactile switches for manual operation, but the AD5228 can also be controlled digitally recommended to add external MOSFETs or transistors that simplify the logic controls. ...
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... Low ESR (equivalent series resistance) 1 µ µF tantalum , and or electrolytic capacitors should be applied at the supplies not important minimize any transient disturbance and to filter low frequency W . The states of the PU ripple. Figure 39 illustrates the basic supply bypassing configu- ration for the AD5228. Rev Page AD5228 10µ ...
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... SET SD 6Ω WHITE V– to limit maximum LED current. R3 should also be used in par- LED D1 allel with AD5228 to limit the LED current within an achievable PWM range. A wider current adjustment range is possible by lowering the ratio as well as changing R3 accordingly. 5V 10µ (7) of the AD5228 is at its L1– ...
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... BUTTON Figure 44. Automatic LCD Panel Backlight Control AUDIO AMPLIFIER WITH VOLUME CONTROL The AD5228 and SSM2211 can form a 1.5 W audio amplifier with volume control that has adequate power and quality for portable devices such as PDAs and cell phones. The SSM2211 can drive a single speaker differentially between Pins 5 and 8 without any output capacitor ...
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... Users who consider EEMEM potentiometers but cannot justify the additional cost and programming for their designs can consider constantly biasing the AD5228 with the supply to retain the resistance setting as shown in Figure 46. The AD5228 is designed specifically with low power to allow power conser- vation even in battery-operated systems. As shown in Figure 47, a similar low power digital potentiometer is biased with a 3 ...
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... AD5228BUJZ50 2 -RL7 50 −40°C to +105°C 2 AD5228BUJZ50 -R2 50 −40°C to +105°C 2 AD5228BUJZ100 -RL7 100 −40°C to +105°C 2 AD5228BUJZ100 -R2 100 −40°C to +105°C AD5228EVAL 10 1 The end-to-end resistance R is available in 10 kΩ, 50 kΩ, and 100 kΩ. The final three characters of the part number determine the nominal resistance value, for AB example,10 kΩ ...
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... NOTES Rev Page AD5228 ...
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... AD5228 NOTES © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04422–0–4/04(0) Rev Page ...