AD5228EVAL Analog Devices Inc, AD5228EVAL Datasheet
AD5228EVAL
Specifications of AD5228EVAL
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AD5228EVAL Summary of contents
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FEATURES 32-position digital potentiometer 10 kΩ, 50 kΩ, 100 kΩ end-to-end terminal resistance Simple manual up/down control Self-contained, requires only 2 pushbutton tactile switches Built-in adaptive debouncer Discrete step-up/step-down control Autoscan up/down control with 4 steps per second Pin-selectable zero-scale/midscale ...
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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 ...
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ELECTRICAL CHARACTERISTICS 10 kΩ, 50 kΩ, 100 kΩ versions ± 10 ± 10 Table 2. Parameter DC CHARACTERISTICS, RHEOSTAT MODE 2 Resistor Differential Nonlinearity 2 Resistor Integral Nonlinearity 3 Nominal Resistor ...
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AD5228 Parameter 4, 9, 10, 11 DYNAMIC CHARACTERISTICS Built-in Debounce and Settling Time 12 PU Low Pulse Width PD Low Pulse Width PU High Repetitive Pulse Width PD High Repetitive Pulse Width Autoscan Start Time Autoscan Time Bandwidth –3 dB ...
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ABSOLUTE MAXIMUM RATINGS Table 3. Parameter V to GND GND PU, PD, PRE Voltage to GND Maximum Current Pulsed Continuous (R ≤ 5 ...
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AD5228 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1 PU Push-Up Pin. Connect to the external pushbutton. Active low. A 100 kΩ pull-up resistor is connected Push-Down Pin. Connect ...
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TYPICAL PERFORMANCE CHARACTERISTICS 0.10 0.08 0.06 5.5V 0.04 2.7V 0.02 0 –0.02 –0.04 –0.06 –0.08 –0. CODE (Decimal) Figure 7. R-INL vs. Code vs. Supply Voltages 0.10 0.08 0.06 0.04 0.02 0 –0.02 –0.04 ...
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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 –0.10 ...
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V = 2.7V DD 100 5. –40 – TEMPERATURE (°C) Figure 19. Wiper Resistance vs. Temperature 150 120 – ...
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AD5228 0 STEP = MIDSCALE, V – ± 10% p –40 –60 100 1k 10k FREQUENCY (Hz) Figure 25. PSRR Δ : 8.32ms @: 8.24ms @: 378mV 1 2 ...
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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 to V ...
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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 WB Whenever the maximum reached, ...
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Potentiometer Mode Operation If all three terminals are used, the operation is called potenti- ometer mode. The most common configuration is the voltage divider operation as shown in Figure 36 Figure 36. Potentiometer ...
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AD5228 POWER-UP AND POWER-DOWN SEQUENCES Because of the ESD protection diodes that limit the voltage compliance at Terminals A, B, and W (Figure 39 important to power on V before applying any voltage to DD Terminals A, B, ...
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APPLICATIONS MANUAL ADJUSTABLE LED DRIVER The AD5228 can be used in many electronics-level adjustments such as LED drivers for LCD panel backlight controls. Figure 41 shows a manually adjustable LED driver. The AD5228 sets the voltage across the white LED ...
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AD5228 AUTOMATIC LCD PANEL BACKLIGHT CONTROL With the addition of a photocell sensor, an automatic brightness control can be achieved. As shown in Figure 44, the resistance of the photocell changes linearly but inversely with the light output. The brighter ...
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CONSTANT BIAS WITH SUPPLY TO RETAIN RESISTANCE SETTING 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 ...
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AD5228 OUTLINE DIMENSIONS INDICATOR 0.10 MAX ORDERING GUIDE 1 Model R (kΩ) Temperature Range AB 2 AD5228BUJZ10 -RL7 10 −40°C to +105°C 2 AD5228BUJZ10 -R2 10 −40°C to +105°C 2 AD5228BUJZ50 -RL7 50 −40°C to +105°C 2 AD5228BUJZ50 -R2 50 ...
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NOTES Rev Page AD5228 ...
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AD5228 NOTES © 2004–2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04422–0–4/09(A) Rev Page ...