RT8121GQW Richtek

RT8121 Single Phase PWM Controller with 1-bit VID General Description Features zz z zz Single Phase Power Conversion RT8121 is a single phase PWM buck controller with one zz z zz One Embedded MOSFET Driver with Internal integrated MOSFET driver for advanced microprocessor Bootstrap Diode application as VR12 VCCIO power. This controller zz z zz 1-bit VID Table for VR12 VCCIO maintains the same features as the multi-phase product zz z zz Continuous Differential Inductor DCR Current Sense family, but reduces the output to one phase for lower current zz z zz Adjustable Soft-Start systems. Features of this controller include adjustable zz z zz Adjustable Frequency Typically at 200kHz operation frequency, power good indication, external error- zz z zz Power Good Indication amp compensation, over voltage protection, over current zz z zz Adjustable Over Current Protection protection, externally adjustable offset voltage, load zz z zz Over Voltage Protection transient enhancement (quick response), and enable/ zz z zz Over Temperature Protection shutdown control to achieve optimal power management zz z zz Small 20-Lead WQFN Package solution for various applications. The RT8121 comes in zz z zz RoHS Compliant and Halogen Free the WQFN-20L 3x3 package. Ordering Information Applications RT8121 z VR12 VCCIO Voltage Regulator Package Type z Low Voltage, High Current DC/DC Converter QW : WQFN-20L 3x3 (W-Type) Lead Plating System Pin Configurations G : Green (Halogen Free and Pb Free) Z : ECO (Ecological Element with (TOP VIEW) Halogen Free and Pb free) Note : Richtek products are : 20 19 18 17 16 FBRTN 1 15 UGATE RoHS compliant and compatible with the current require- 2 14 SS PHASE ments of IPC/JEDEC J-STD-020. COMP 3 GND 13 VCC12 FB 4 12 LGATE 21 Suitable for use in SnPb or Pb-free soldering processes. 5 11 ADJ OCSET 6 7 8 9 10 Marking Information RT8121GQW WQFN-20L 3x3 J1= : Product Code YMDNN : Date Code J1=YM DNN RT8121ZQW J1 : Product Code YMDNN : Date Code J1 YM DNN DS8121-02 May 2011 www.richtek.com 1 OFS GND RT/EN GND VCC5 VID ISP PGOOD ISN BOOTV IN 4.5 to 13.2V C11 RT8121 R19 R20 R1 5 C1 16 NTC ADJ BOOT Q1 15 UGATE 13 VCC12 12V R2 L 14 C9 PHASE V O T U GND Q2 12 C3 R4 C14 R3 LGATE 7 RT/EN C2 Q3 R5 R EN RT 9 ISP R6 10 11 ISN OCSET R15 R16 D1 C5 R8 8 VCC5 R12 R7 Option 4 R11 C10 R14 6 OFS C6 R10 R9 Option for V CC SNS Positive OFS Option for R13 Negative R21 C7 C8 OFS 1 FBRTN V SS SNS 18 VID C12 C13 2 17 SS PGOOD PGOOD R17 V TT RT8121 Typical Application Circuit 19, 20, 21 (Exposed Pad) Load Function Block Diagram VCC12 Fault Logic BOOT Offset OFS Transient UGATE Driver MOSFET Response Logic PHASE Driver Enhancement LGATE GND - FB EA COMP + + CMP PWM - OV Modulation Thermal OT RT/EN Waveform Protection Generator 150mV + EAP - OCSET VR11 VID VID OC + + Table - FBRTN /10 ADJ VID Off OV Current ISP OC SS Sense ISN Soft Start OT and Fault Driver Logic PGOOD Logic VCC12 POR Power On 5V Reset Regulator VCC5 www.richtek.com DS8121-02 May 2011 2 F B 3 COMP + -