DWA structure and method thereof, digital-to-analog signal conversion method and signal routing method

7,486,210

11/835094

August 07, 2007

A data weighted average (DWA) structure including a first delay unit, a binary to thermometer code converter, an adder, a second delay unit, a decoder, a barrel shifter, and a plurality of signal lines is provided. The first delay unit delays an input digital signal. The binary to thermometer code converter converts an output signal of the first delay unit into a thermal code. The second delay unit delays an output signal of the adder. The adder adds the input digital signal to an output signal of the second delay unit. The decoder decodes the output signal of the second delay unit. The barrel shifter generates an output signal from the thermal code in accordance with an output signal of the decoder. The signal lines route the output signal of the barrel shifter into two independent control signal groups.

Hong, Ghia-Ming (Hsinchu, TW); Chang, Chia-Wei (Taichung County, TW); Peng, Yan-Hua (Hsinchu, TW); Liu, Kuang-Chih (Hsinchu, TW); Lin, Chung-Fu (Taipei County, TW)

Faraday Technology Corp. (Hsinchu, TW)

1. A data weighted average (DWA) structure, comprising: a first delay unit, receiving and delaying an input digital signal; a binary to thermometer code converter, receiving an output signal from the first delay unit and converting the output signal of the first delay unit into a thermal code; an adder, receiving the input digital signal; a second delay unit, receiving and delaying an output signal of the adder, an output signal of the second delay unit further feeding back to the adder, the adder adding the input digital signal to the output signal of the second delay unit to obtain the output signal of the adder; a decoder, receiving and decoding the output signal of the second delay unit; a barrel shifter, receiving the thermal code from the binary to thermometer code converter and generating an output signal according to an output signal of the decoder; and a plurality of signal lines, routing an odd bit in the output signal of the barrel shifter into a low-bit signal of a DWA output digital signal, and routing an even bit in the output signal of the barrel shifter into a high-bit signal of the DWA output digital signal.

2. The DWA structure according to claim 1 , wherein the first delay unit and the second delay unit operate synchronously.

3. The DWA structure according to claim 1 , wherein a connection between the odd bit in the output signal of the barrel shifter and the low-bit signal of the DWA output digital signal constructed by the signal lines is: B (2 i −1)= S (i) wherein B(2i−1) represents the odd bit in the output signal of the barrel shifter, S(i) represents the low-bit signal of the DWA output digital signal, i is a positive integer between 1 and M/2, and M is the bit number of the output signal of the barrel shifter.

4. The DWA structure according to claim 1 , wherein a connection between the even bit in the output signal of the barrel shifter and the high-bit signal of the DWA output digital signal constructed by the signal lines is: B (2 i)= S (M+ 1− i) wherein B(2i) represents the odd bit in the output signal of the barrel shifter, S(M+1−i) represents the high-bit signal of the DWA output digital signal, i is a positive integer between 1 and M/2, and M is the bit number of the output signal of the barrel shifter.

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