1. HPZ1608U101-2R0TF Substitution Conclusion The HPZ1608U101-2R0TF is fully package-compatible (0603) with the original HPZ1608D121-1R5TF. The key differences are: its impedance is reduced from 120 Ohms @ 100 MHz to 100 Ohms @ 100 MHz, its current rating is increased from 1.5A to 2A, and its DC resistance (DCR) is lowered from 70mOhm to 55mOhm. The lower impedance (a decrease of approximately 16.7%) may result in a slight reduction in high-frequency noise suppression at 100 MHz, potentially degrading filter performance. If the original circuit has a strict impedance requirement (e.g., in EMI suppression designs), substitution could lead to diminished noise filtering. Conversely, the higher current rating provides a greater current handling margin (an increase of ~33%), and the lower DCR reduces DC voltage drop and power loss. This makes the substitute suitable for applications with higher current demands or those sensitive to power dissipation. Feasibility depends on the application: substitution is acceptable if the circuit can tolerate a moderate impedance reduction while prioritizing current capability and efficiency. It is not recommended if impedance is a critical design parameter, such as in precision filtering circuits.