| 摘要 |
The present invention provides a D/A converter which has a small area in the chip, a linear current output and a high-speed operation. Each of resistors R11-Rn1 in a resistor train 11a is composed of four MOS transistors which are connected in parallel with each other and each of resistors R12-Rn2 in a resistor train 11b is composed of four MOS transistors which are connected in parallel with each other. Between the connecting nodes of the resistor trains 11a, 11b, MOS transistors ST11, ST12, ST13, ST14-STn1, STn2, STn3 and STn4 which serve as switches and resistors are connected. All the MOS transistors have the same conductive type and size. Gate control signals C11-Cn1; C12-Cn2 turn MOS transistors ON but each of them has a different voltage value. A current difference between the output terminals Za and Zb is converted into a voltage difference by an operational amplifier or the like.
|
