ad1990xcpzrl Analog Devices, Inc., ad1990xcpzrl Datasheet - Page 14

• Manufacturer Part Number: ad1990xcpzrl
• Description: Audio Switching Amplifier
• Manufacturer: Analog Devices, Inc.

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.
Using an External Clock Source
If a clock signal of the appropriate frequency already exists in
the application circuit, connect it directly to CLKI and leave
CLKO floating. The logic levels of the square wave should be
compatible with those defined in Specifications section.
Large amounts of jitter on the clock input degrade performance.
Whenever possible, avoid passing the clock signal through
programmable logic and other circuits with unknown or variable
propagation delay. In general, clock signals suitable for audio ADCs
or DACs are also appropriate for use with the AD1990.
22pF
Figure 25. Crystal Connection
XTAL
47Ω
22pF
Rev. 0 | Page 14 of 16
Clocking Multiple Amplifiers in Parallel
If there are multiple AD199x family amplifiers connected to the
same PV
derivatives) for each amplifier as previously described. Avoid
clocking amplifiers from similar but asynchronous clocks if
they use the same power supply because this can result in beat
frequencies.
PROTECTION CIRCUITS AND ERROR REPORTING
Thermal Protection
The AD1990 features thermal protection. When the die
temperature exceeds approximately 135°C, the thermal warning
error output ( ERR1 ) is asserted. If the die temperature exceeds
approximately 150°C, the thermal shutdown error output
( ERR2 ) is asserted. If this occurs, the part shuts down to
prevent damage to the part. When the die temperature drops
below approximately 120°C, the part returns to normal
operation automatically and negates both error outputs.
Overcurrent Protection
The AD1990 features over current or short-circuit protection. If
the current through any power transistors exceeds approximately
4 A, the part enters a mute state and the overcurrent error
output ( ERR0 ) is asserted. This is a latched error and does not
clear automatically. Restore normal operation and clear the
error condition by either asserting and then negating RESET or
by asserting and then negating MUTE .
DD
supply, use the same clock source (or synchronous