XC9128 datasheetXC9128/XC9129 Series 1A Driver Transistor Built-In, Step-Up DC/DC Converters ETR0411-004 The XC9128/XC9129 series are synchronous step-up DC/DC converters with a 0.2Ω (TYP.) N-channel driver transistor and a GENERAL DESCRIPTION synchronous 0.2Ω (TYP.) P-channel switching transistor built-in. A highly efficient and stable current can be supplied up to 1.0A by reducing ON resistance of the built-in transistors. With a high switching frequency of 1.2MHz, a small inductor is selectable making the series ideally suited for applications requiring low profile or space saving solutions. With the MODE pin, the series provides mode selection of PWM control or PFM/PWM automatic switching control. In the PWM/PFM automatic switching mode, the series switches from PWM to PFM to reduce switching loss……