AD1990 Analog Devices, AD1990 Datasheet
AD1990
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AD1990 Summary of contents
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... Analog Devices. Trademarks and registered trademarks are the property of their respective owners. GENERAL DESCRIPTION The AD1990 is a 2-channel, bridge tied load (BTL), switching audio power amplifier with integrated Σ-Δ modulator. The modulator accepts a single-ended, analog input signal and converts switching waveform to drive speakers directly ...
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... AD1990 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configuration and Function Descriptions............................. 6 Typical Performance Characteristics ............................................. 8 Theory of Operation ...................................................................... 11 REVISION HISTORY 4/06—Revision 0: Initial Version Overview ..................................................................................... 11 Σ-Δ Modulator............................................................................ 11 MUTE and RESET ..................................................................... 11 Gain Structure............................................................................. 11 Power Stage ...
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... kHz Max Unit Test Conditions/Comments 355 mΩ 25°C 265 mΩ 25°C A Peak °C Die temperature °C Die temperature °C Die temperature = kHz kHz kHz kHz kHz O AD1990 ...
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... AD1990 Table 5. Power Supplies Parameter ANALOG SUPPLY DIGITAL SUPPLY POWER TRANSISTOR SUPPLY RESET/POWER-DOWN CURRENT QUIESCENT CURRENT OPERATING CURRENT Table 6. Digital I/O Parameter INPUT LOGIC HIGH INPUT LOGIC LOW OUTPUT LOGIC HIGH ...
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... V to +0.3 V section of this specification is not implied. Exposure to absolute −0 +0.5 V maximum rating conditions for extended periods may affect –40°C to +85°C device reliability. –65°C to +150°C 150°C 19.2°C/W 0.9°C/W 9.7°C/W Rev Page AD1990 ...
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... OUTR+ O 46, 47, 48, 49 PGND2 50 NFR NFR− I PGND1 1 PIN 1 INDICATOR PGND1 2 PGND1 3 OUTL+ 4 OUTL+ 5 OUTL+ 6 AD1990 PVDD1 7 PVDD1 8 TOP VIEW PVDD1 9 (Not to Scale) PVDD1 10 OUTL– 11 OUTL– 12 OUTL– 13 PGND1 14 PGND1 15 PGND1 16 Figure 3. Pin Configuration Description Negative Power Supply. Used for the A2 and B2 high power transistors. ...
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... Modulator Filter Pin—Used to Set Time Constant of Modulator Order Reduction Circuit. Analog Input for Left Channel. Left Channel Negative Feedback—Inverting Input. Left Channel Negative Feedback—Noninverting Input. Negative Power Supply. Used for the A2 and B2 high power transistors. Rev Page AD1990 ...
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... AD1990 TYPICAL PERFORMANCE CHARACTERISTICS 0 –20 –40 –60 –80 –100 –120 –140 –160 FREQUENCY (kHz) Figure Output Power into 4 Ω Load 0 –20 –40 –60 –80 –100 –120 –140 –160 FREQUENCY (kHz) Figure Output Power into 6 Ω Load 0 – ...
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... Figure 14. THD vs. Frequency Output Power into 6 Ω Load, PVDD = 0.1 0.01 0.001 0.0001 10k 100 Figure 15. THD vs. Frequency Output Power into 8 Ω Load, PVDD = 12 V Rev Page AD1990 –40 –50 –60 –70 –80 –90 –100 –110 –120 1k 10k FREQUENCY (Hz) – ...
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... AD1990 100 10 1 0.1 THD + N 0.01 THD 0.001 0.1 1 OUTPUT POWER (W) Figure 16. THD and THD + N vs. Output Power, 1 kHz Sine, 4 Ω Load, PVDD = 12 V 100 10 1 0.1 THD + N 0.01 THD 0.001 0.1 1 OUTPUT POWER (W) Figure 17. THD and THD + N vs. Output Power, 1 kHz Sine, 6 Ω Load, PVDD = 12 V 100 ...
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... MODULATOR The AD1990 is a switching type, also known as a Class-D, audio power amplifier. This class of amplifiers maximizes efficiency by only using its power output devices in full-on or full-off states. While most Class-D amplifiers use some variation of pulse-width modulation (PWM), the AD1990 uses Σ ...
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... Figure 22. AC-Coupled Input Signal Setting the Modulator Gain The AD1990 modulator uses a combination of the input signal and feedback from the power output stage to calculate its two- state output pattern. The feedback input nodes are part of the internal analog circuit that operates from the power supply ...
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... Output Transistor Nonoverlap Time The AD1990 allows the user to select from one of eight different nonoverlap times, as shown in Figure 24. Nonoverlap time prevents or minimizes the period during which both the high- side and low-side devices are on simultaneously due to propagation delays and nonzero rise and fall times ...
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... AD1990 Using a Crystal Oscillator The AD1990 can use a crystal connected to the CLKI and CLKO pins as a master clock source, as shown in Figure 25. The CLKI and CLKO pins connect to an internal inverter to create a full resonator. The typical values shown work in many applications, but the crystal manufacturer should provide the exact type and value of the capacitors and the resistor ...
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... DCTRL1 DCTRL0 MUTE NFR– RESET ERR2 OUTR– ERR1 ERR0 CLKI CLKO Figure 26. Typical Application Circuit Rev Page 0.1µF + 0.1µF 1000µ 4.2kΩ 1.8kΩ 18µ 1µF LOAD = 6Ω AD1990 ...
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... Temperature Range 1 AD1990ACPZ −40°C to +85°C 1 AD1990ACPZRL −40°C to +85°C 1 AD1990ACPZRL7 −40°C to +85°C EVAL-AD1990EB Pb-free part. ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 9.00 BSC SQ 0.60 MAX ...