RT9187B 600mA, Ultra-Low Dropout, Ultra-Fast CMOS LDO Regulator General Description Features Ultra-Low-Noise for RF Application The RT9187B is a high-performance, 600mA LDO regulator, Ultra-Fast Response in Line/Load Transient offering extremely high PSRR and ultra-low dropout. This Quick Start-Up (Typically 40s) chip is ideal for portable RF and wireless applications <0.1A Standby Current When Shutdown with demanding performance and space requirements. Low Dropout : 100mV at 500mA A noise reduction pin is also available for further reduction Wide Operating Voltage Ranges : 2.5V to 5.5V of output noise. Regulator ground current increases only TTL-Logic-Controlled Shutdown Input slightly in dropout, further prolonging the battery life. The Current Limiting Protection RT9187B also works well with low-ESR ceramic Thermal Shutdown Protection capacitors, reducing the amount of board space necessary Only 2.2F Output Capacitor Required for Stability for power applications, critical in hand-held wireless High Power Supply Rejection Ratio devices. RoHS Compliant and Halogen Free The RT9187B consumes less than 0.1A in shutdown mode and has fast turn-on time for less than 40s. The Applications other features include ultra-low dropout voltage, high CDMA/GSM Cellular Handsets output accuracy, current limiting protection, and high ripple Battery-Powered Equipment rejection ratio. The RT9187B is available in the SOT-23-5 Laptop, Palmtops, Notebook Computers package. Hand-Held Instruments Mini PCI & PCI-Express Cards Ordering Information PCMCIA & New Cards RT9187B Portable Information Appliances Package Type B : SOT-23-5 Pin Configurations Lead Plating System (TOP VIEW) G : Green (Halogen Free and Pb Free) Note : VOUT ADJ Richtek products are : 5 4 RoHS compliant and compatible with the current require- 23 ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. VIN GND EN SOT-23-5 Marking Information 04= : Product Code 04=DNN DNN : Date Code Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS9187B-03 March 2012 www.richtek.com 1RT9187B Typical Application Circuit 1 5 V VIN VOUT V IN OUT C IN C OUT RT9187B 2.2F R1 2.2F 4 ADJ 3 Chip Enable EN R2 GND 2 R1 V = 0.8 x ( ) Volts 1 + OUT R2 Note : The value of R2 should be less than 80k to maintain regulation. Function Pin Description Pin No. Pin Name Pin Function 1 VIN Voltage Input. 2 GND Ground. 3 EN Chip Enable (Active High). 4 ADJ Output Voltage Feedback. 5 VOUT Voltage Output. Function Block Diagram VIN EN OTP EN POR BIAS - + V REF VOUT Current Limit Quick start ADJ GND Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS9187B-03 March 2012 2