# Differential Phase Coupler Using Balun-Type Power Divider

## TL;DR

This paper introduces a compact differential phase coupler design for 6 GHz WiFi applications using the IPD process.

## Contribution

A novel differential phase coupler design using a balun-type power divider in the IPD process is proposed.

## Key findings

- The coupler achieved reflection coefficients below −19 dB at 6 GHz.
- The design had an insertion loss of 1.76 dB and isolation of 20 dB.
- The core chip size was 0.02λ0 × 0.018λ0, demonstrating compactness.

## Abstract

This paper presents a differential phase coupler design methodology in the IPD process. The coupler consists of a balun and two phase-shifter circuits. The compact balun was designed with lumped components and a common inductor. Each output of the balun circuit was connected to a phase shifter with an opposite phase to make a desired output phase. In the design example, a three-port 90-degree hybrid coupler was implemented on the IPD process to operate at the 6 GHz WIFI frequency. The post-simulation showed that all reflection coefficients were below −19 dB, with an insertion loss of 1.76 dB and isolation of 20 dB. The core chip size was only 0.02λ0 × 0.018λ0.