| 摘要 |
PROBLEM TO BE SOLVED: To realize a D/A(digital/analog) converter circuit that can output a desired analog voltage with high precision even when many numbers of conversion bits are required with a small chip area. SOLUTION: The high precision D/A converter circuit is provided with a high-order digital/analog converter circuit section 100 that provides an output of a 1st voltage Va and a 2nd voltage Vb obtained by D/A-converting high-order 5-bits in a 13-bit input code to 1st and 2nd output nodes 11, 12 via two buffers 10a, 10b each having the same characteristic, a low-order digital/analog converter circuit section 200 that provides an output of a voltage obtained by D/A-converting low-order 8-bits of the input code to a 3rd output node 13 by using the voltages of the two output nodes for a reference voltage of an R-2R ladder type circuit, a sample-hold section 250 that selectively samples and holds the voltage of the 3rd output node 13 being D/A conversion output of the 13-bit input code in response to a value of the input code, and an output section 300 that multiplies the D/A-converted output voltage that receives sample and hold processing with a gain around an optional voltage Vc as a center.
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