RT9187 1A, Ultra-Low Dropout, Ultra-Fast CMOS LDO Regulator General Description Features Ultra-Low-Noise for RF Application The RT9187 is a high-performance, 1A LDO regulator, Ultra-Fast Response in Line/Load Transient offering extremely high PSRR and ultra-low dropout. Ideal Quick Start-Up (Typically 40s) for portable RF and wireless applications with demanding <0.1A Standby Current When Shutdown performance and space requirements. Low Dropout : 240mV at 1A 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 RT9187 also works with low-ESR ceramic capacitors, Thermal Shutdown Protection reducing the amount of board space necessary for power Only 2.2F Output Capacitor Required for Stability applications, critical in hand-held wireless devices. High Power Supply Rejection Ratio RoHS Compliant and 100% Lead (Pb)-Free The RT9187 consumes less than 0.1A in shutdown mode and has fast turn-on time less than 40s. The other features Applications include ultra-low dropout voltage, high output accuracy, CDMA/GSM Cellular Handsets current limiting protection, and high ripple rejection ratio. Battery-Powered Equipment Available in the VDFN-8L 3x3 and SOP-8 (Exposed Pad) Laptop, Palmtops, Notebook Computers package. Hand-Held Instruments Mini PCI & PCI-Express Cards Ordering Information RT9187(- ) PCMCIA & New Cards Package Type Portable Information Appliances QV : VDFN-8L 3x3 (V-Type) SP : SOP-8 (Exposed Pad-Option 1) Marking Information Lead Plating System For marking information, contact our sales representative P : Pb Free G : Green (Halogen Free and Pb Free) directly or through a RichTek distributor located in your area. None : Adjustable Output Fixed Output Voltage Code 10 : 1.0V Pin Configurations 11 : 1.1V (TOP VIEW) : 32 : 3.2V 1 8 VIN EN 33 : 3.3V 2 7 VIN NC 1L : 1.34V 3 6 VOUT GND Note : 4 9 5 VOUT BP/ADJ Richtek products are : VDFN-8L 3x3 RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020. VIN 8 EN Suitable for use in SnPb or Pb-free soldering processes. VIN 2 7 NC GND VOUT 3 6 GND 9 VOUT 4 5 BP/ADJ SOP-8 (Exposed Pad) DS9187-11 June 2011 www.richtek.com 1 GNDRT9187 Typical Application Circuit V VIN VOUT V IN OUT VIN VOUT V V IN OUT C IN C OUT C IN C OUT 2.2F 2.2F 2.2F R1 2.2F RT9187 RT9187 BP ADJ C Chip Enable BP EN 10nF Chip Enable EN R2 GND GND Figure 1. Fixed Operation Figure 2. Adjustable Operation 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 Pin Function Fixed Output Adjustable Name Voltage Output Voltage 1 1 VIN Supply Input. 2 2 VIN Supply Input. 3 3 VOUT Regulator Output. 4 4 VOUT Regulator Output. Noise Reduction. Connecting a 10nF capacitor to GND to 5 -- BP reduce output noise. If external feedback resistors are applied, the output voltage will be: -- 5 ADJ R1 V = 0.8 (1+ ) V OUT R2 6, 6, Ground. The exposed pad must be soldered to a large PCB and GND 9 (Exposed Pad) 9 (Exposed Pad) connected to GND for maximum power dissipation. 7 7 NC No Internal Connection. Enable Input Logic, Active High. When the EN goes to a logic 8 8 EN low, the device is in shutdown mode. www.richtek.com DS9187-11 June 2011 2