发明名称 |
Segmented DAC using PMOS and NMOS switches for improved span |
摘要 |
A digital-to-analog converter with cascaded coarse and fine resistor divider strings. The fine resistor string contains 2N or more resistor segments controlled by N number of fine divider control bits. Resistors located at each end of the fine divider string are a fraction of the nominal value for the remaining fine divider resistor segments. The on-resistance of switches coupling the coarse and fine resistor divider strings is less than or equal to a predetermined fraction of the nominal value for the fine divider resistor segments to minimize contributions to linearity error. The DAC uses all CMOS devices including NMOS and PMOS switches which utilize approximately the full rail-to-rail voltage of the voltage source without the use of additional amplifiers. The DAC provides linearity of about one-fourth LSB.
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申请公布号 |
US5999115(A) |
申请公布日期 |
1999.12.07 |
申请号 |
US19980063242 |
申请日期 |
1998.04.20 |
申请人 |
MOTOROLA, INC. |
发明人 |
CONNELL, LAWRENCE E.;DRIBINSKY, ALEXANDER |
分类号 |
H03M1/68;H03M1/76;(IPC1-7):H03M1/68 |
主分类号 |
H03M1/68 |
代理机构 |
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