SI91821

Si91821 Vishay Siliconix Micropower 300-mA CMOS LDO Regulator With Error Flag FEATURES D Input Voltage: 2.35−6.0 V D Fixed 1.8-V, 2.5-V, 2.8-V, 3.0-V, 3.3-V, 5.0-V, or Adjustable Output Voltage Options D Low 120-mV Dropout at 300-mA Load D Guaranteed 300-mA Output Current D 500-mA Peak Output Current Capability D Uses Low ESR Ceramic Output Capacitor D Fast Load and Line Transient Response D Only 100-mV(rms) Noise With Noise Bypass Capacitor D 1-mA Maximum Shutdown Current D Built-in Short Circuit and Thermal Protection D Out-Of-Regulation Error Flag (Power_Good) Available APPLICATIONS D Cellular Phones D Laptop and Palm Computers D PDA, Digital Still Cameras DESCRIPTION The Si91821 is a 300-mA CMOS LDO (low dropout) voltage regulator. The device features ultra low ground current and dropout voltage to prolong battery life in portable electronics. The Si91821 offers line and load transient response and ripple rejection superior to that of bipolar or BiCMOS LDO regulators. The device is designed to maintain regulation while delivering 500-mA peak current. This is useful for systems that have high surge current upon turn-on. The Si91821 is designed to drive the lower cost ceramic, as well as tantalum, output capacitors. The device is guaranteed stable from maximum load current down to 0-mA load. In addition, an external noise bypass capacitor connected to the device’s CNOISE pin will lower the LDO’s output noise for low noise applications. The Si91821 also includes an out-o...