In this paper, a novel field-programmable analog array (FPAA) is proposed to secure the intellectual property (IP) of analog and mixed-signal circuits. A topology obfuscation technique is developed to efficiently mask both differential mode and single-ended mode analog circuit. The circuits implemented on the FPAA include an op amp with varying loads, a second order biquad filter, a ring-oscillator, and a frequency divider. The security provided by the FPAA fabric is evaluated by analyzing the security robustness of both single CAB implementations and multi-CAB systems. Two attack scenarios are considered, a brute force attack and a topology attack.