This paper presents a low power, small area Frequency Acquisition Circuit (FAC) for a pulse-based inductive coupling transceiver. A multiphase clock which is generated in array oscillator is used to control the pulse width. To solve the problem of oscillation frequency change by PVT variation, FAC is proposed to control the oscillation frequency. FAC uses the multiphase clock generated in array oscillator. By sharing the multiphase clock for both the pulse generation and the frequency control, low power and small area can be achieved. The fabricated test chip in 65nm CMOS occupies 0.045mm2. The array oscillator generates 1GHz, 20 phase clocks at the supply voltage of 0.8V. The RMS of cycle-to-cycle jitter is 3.3ps and the power consumption is 1.1mW.