RT9018A/B Maximum 3A, Ultra Low Dropout Regulator General Description Features zz z zz Maximum 3A Low-Dropout Voltage Regulator The RT9018A/B is a high performance positive voltage zz z zz High Accuracy Output Voltage 1.5% regulator designed for use in applications requiring very zz z zz Typically 210mV Dropout at 3A low Input voltage and very low dropout voltage at up to zz z zz Power Good Output 3A(Peak). It operates with a VIN as low as 1.4V and VDD zz z zz Output Voltage Pull Low Resistance when Disable voltage 3V with output voltage programmable as low as zz z zz Thermal and Over Current Protection 0.8V. The significant feature includes ultra low dropout, zz z zz RoHS Compliant and 100% Lead (Pb)-Free ideal for applications where VOUT is very close to VIN. Additionally, there is an enable pin to further reduce power Applications dissipation while shutdown. The RT9018A/B provides z Front Side Bus VTT (1.2V/3A) excellent regulation over variations in line, load and z NoteBook PC Applications temperature. and provides a power OK signal to indicate z Motherboard Applications if the voltage level of Vo reaches 90% of its rating value. The RT9018A/B is available in the SOP-8 (Exposed Pad) Marking Information and WDFN-10L 3x3 packages with 1V, 1.05V, 1.2V, 1.5V, For marking information, contact our sales representative 1.8V and 2.5V internally preset outputs that are also directly or through a Richtek distributor located in your adjustable using external resistors. area. Ordering Information Pin Configurations RT9018A/B- Package Type (TOP VIEW) SP : SOP-8 (Exposed Pad-Option 1) QW : WDFN-10L 3x3 8 PGOOD GND Lead Plating System 2 7 EN ADJ GND P : Pb Free 3 6 VIN VOUT 9 G : Green (Halogen Free and Pb Free) 4 VDD 5 NC Z : ECO (Ecological Element with Halogen Free and Pb free) SOP-8 (Exposed Pad) Output Voltage 10 : 1V/Adj VOUT 1 10 VDD 1K : 1.05V/Adj VOUT 2 9 VIN GND VOUT 3 8 VIN 12 : 1.2V/Adj ADJ 4 7 VIN 15 : 1.5V/Adj 11 PGOOD 5 EN 18 : 1.8V/Adj 25 : 2.5V/Adj WDFN-10L 3x3 Enable Pin Function A : Internal Pull High B : Internal Pull Low Note : Richtek products are : RoHS compliant and compatible with the current require- ments of IPC/JEDEC J-STD-020. Suitable for use in SnPb or Pb-free soldering processes. Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. DS9018A/B-09 April 2012 www.richtek.com 1 9RT9018A/B Typical Application Circuit R1+ R2 V = 0.8 OUT R2 VIN V VOUT V IN OUT VIN V V IN VOUT OUT C Dummy 10F R1 10F RT9018A/B 10F RT9018A/B 10F Chip Enable Chip Enable ADJ EN ADJ EN PGOOD R2 PGOOD V VDD DD V VDD DD GND 100k GND 100k 1F 1F V OUT V OUT Figure 1. Fixed Voltage Regulator Figure 2. Adjustable Voltage Regulator Function Pin Description Pin No. Pin Pin Function SOP-8 Name WDFN-10L 3x3 (Exposed Pad) 3 7, 8, 9 VIN Supply Input Voltage. 2 6 EN Chip Enable (Active-High). 4 10 VDD Supply Voltage of Control Circuitry. 1 5 PGOOD Power Good Open Drain Output. Set the output voltage by the internal feedback resistors when 7 4 ADJ ADJ is grounded. If external feedback resistors is used, V = OUT 0.8V x (R1 + R2)/R2. 6 1, 2, 3 VOUT Output Voltage. 5 -- NC No Internal Connection. 8, Ground. The exposed pad must be soldered to a large PCB 11 (Exposed Pad) GND 9 (Exposed Pad) and connected to GND for maximum power dissipation. Function Block Diagram VIN VOUT OCP Driver Error OTP Amplifier POR EN Mode ADJ VDD 0.8V PGOOD - + 0.72V GND Copyright 2012 Richtek Technology Corporation. All rights reserved. is a registered trademark of Richtek Technology Corporation. www.richtek.com DS9018A/B-09 April 2012 2 + -