Transmit digital to analog converter (DAC) spur attenuation
First Claim
1. A method of attenuating spurs in a digital to analog converter (DAC), comprising:
- injecting a reference voltage into an amplifier;
measuring an output of a ground low drop-out regulator;
comparing an output of the ground low drop-out regulator with the reference voltage; and
adjusting an output of the amplifier based on the comparison.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and apparatus for attenuating transmit digital to analog converter (DAC) spurs is provided. The method begins when a reference voltage is injected into an amplifier. Next, an output of the ground low drop-out regulator is measured and is them compared with the reference voltage. The output of the amplifier is then adjusted based on the results of the comparison. If the reference voltage is higher then the output of the ground low drop-out regulator the output of the amplifier is adjusted to ground. If the reference voltage is lower than the output of the ground low drop-out regulator then the output of the amplifier is adjusted to match the reference voltage.
-
Citations
22 Claims
-
1. A method of attenuating spurs in a digital to analog converter (DAC), comprising:
-
injecting a reference voltage into an amplifier; measuring an output of a ground low drop-out regulator; comparing an output of the ground low drop-out regulator with the reference voltage; and adjusting an output of the amplifier based on the comparison.
-
-
2. A method of attenuating spurs in a digital to analog converter (DAC), comprising:
-
injecting a reference voltage into an amplifier; measuring an output of a ground low drop-out regulator; comparing an output of the ground low drop-out regulator with the reference voltage; and adjusting an output of the amplifier based on the comparison wherein if the output comparison indicates the reference voltage is higher than the output of the ground low drop-out regulator, adjusting the output of the amplifier to ground. - View Dependent Claims (3, 4)
-
-
5. A method of attenuating spurs in a digital to analog converter (DAC), comprising:
-
injecting a reference voltage into an amplifier; measuring an output of a ground low drop-out regulator; comparing an output of the ground low drop-out regulator with the reference voltage; and adjusting an output of the amplifier based on the comparison wherein if the output comparison indicates the reference voltage is lower than the output of the ground low drop-out regulator, adjusting the output of the amplifier to match the reference voltage. - View Dependent Claims (6, 7)
-
-
8. An apparatus for transmit digital to analog converter (DAC) spur attenuation, comprising:
-
an amplifier; a first transistor in communication with the amplifier; a second transistor in communication with the first transistor; a third transistor in communication with the second transistor; a fourth transistor in communication with the first and second transistors; and a ground low drop-out regulator (GND LDO). - View Dependent Claims (9, 10, 11)
-
-
12. An apparatus for transmit digital to analog converter (DAC) spur attenuation, comprising:
-
an amplifier; a first transistor in communication with the amplifier; a second transistor in communication with the first transistor; a third transistor in communication with the second transistor; a fourth transistor in communication with the first and second transistors; and a ground low drop-out regulator (GND LDO), wherein the GND LDO is connected to the fourth transistor, and further wherein the fourth transistor is also connected to a noisy ground.
-
-
13. An apparatus for attenuating spurs in a transmit digital to analog converter (DAC), comprising:
-
means for injecting a reference voltage into an amplifier; means for measuring an output of a ground low drop-out regulator; means for comparing an output of the ground low drop-out regulator with the reference voltage; and means for adjusting an output of the amplifier based on the comparison.
-
-
14. An apparatus for attenuating spurs in a transmit digital to analog converter (DAC), comprising:
-
means for injecting a reference voltage into an amplifier; means for measuring an output of a ground low drop-out regulator; means for comparing an output of the ground low drop-out regulator with the reference voltage; and means for adjusting an output of the amplifier based on the comparison; and further comprising;
means for adjusting the output of the amplifier to ground if the output comparison indicates the reference voltage is higher than the output of the ground low drop-out regulator. - View Dependent Claims (15)
-
-
16. An apparatus for attenuating spurs in a transmit digital to analog converter (DAC), comprising:
-
means for injecting a reference voltage into an amplifier; means for measuring an output of a ground low drop-out regulator; means for comparing an output of the ground low drop-out regulator with the reference voltage; means for adjusting an output of the amplifier based on the comparison; and further comprising;
means for adjusting the output of the amplifier to match the reference voltage if the comparison indicates that the output of the ground low drop-out regulator is lower than the reference voltage. - View Dependent Claims (17)
-
-
18. A non-transitory computer-readable medium containing instructions, which when executed cause a processor to perform the steps of:
- injecting a reference voltage into an amplifier;
injecting a reference voltage into an amplifier; measuring an output of a ground low drop-out regulator; comparing an output of the ground low drop-out regulator with the reference voltage; and adjusting an output of the amplifier based on the comparison.
- injecting a reference voltage into an amplifier;
-
19. A non-transitory computer-readable medium containing instructions, which when executed cause a processor to perform the steps of:
- injecting a reference voltage into an amplifier;
injecting a reference voltage into an amplifier; measuring an output of a ground low drop-out regulator; comparing an output of the ground low drop-out regulator with the reference voltage; and adjusting an output of the amplifier based on the comparison; and further comprising instructions for adjusting the output of the ground low drop-out regulator to ground if the reference voltage is higher than the output of the ground low drop-out regulator. - View Dependent Claims (20, 21, 22)
- injecting a reference voltage into an amplifier;
Specification