摘要
高精度D/A转换器的实际精度往往低于理论上的精度。针对这个长期困扰的难题,在设计16位D/A转换器的过程中,提出了一种熔丝修调技术,即通过修调电流源输出端的电流,有效地减小电流源失配和有限输出阻抗对D/A转换器的DNL和INL的影响,大幅度提高D/A转换器的精度。基于0.18μm CMOS工艺的测试结果表明:在采用熔丝修调技术前,该电路的DNL和INL分别为-0.72~9.07LSB和-5.55~18.1LSB;在采用熔丝修调技术后,该电路的DNL和INL分别为-3.95~0.70LSB和1.94~8.06LSB。当输入信号频率为102 MHz、采样频率为500MHz时,SFDR达到82.16dBc,完全满足D/A转换器高精度的要求。
The actual precisions of D/A converters are often lower than the theoretical precisions, especially for high accuracy D/A converters. Aimed at this long-term vexed problem in 16-bit D/A converters, a fuse trimming technique was proposed. By trimming the output current of current sources, the influence of current source＇s mismatch and finite output impedance on the DNL and INL of the D/A converters could be effectively reduced, so the accuracy of the D/A converters could be greatly improved. Based on a 0.18 μm CMOS process, the tested results showed that the measured DNL and INL were -0.72 - 9.07 LSB, -5.55 - 18.1 LSB respectively before fuse trimming, and the measured DNL and INL were -0.70-3.95 LSB, 1.94-8.06 LSB respectively after fuse trimming. The SFDR was 82.16 dBc at 500 MHz sampling Irequency and 102 MHz input signal frequency. It met the requirements of high precision for D/A converters.
出处
《微电子学》
CSCD
北大核心
2017年第3期317-321,共5页
Microelectronics
