RT9221

RT9221 Programmable Synchronous PWM Buck Converter with 1.5V/2.5V Dual Low Dropout Linear Regulator Controller General Description The RT9221 integrates a PWM controller and two low-dropout linear regulators into a single chip. The PWM controller provides the CPU core voltage controlled by a 5-bit DAC and the linear section regulates power for GTL bus, clock driver or other circuits on motherboards. The PWM controller provides an adjustable Intel-compatible 1.3V~3.5V output voltage. The synchronous N-MOSFET driver with 200 KHz switching frequency optimizes the efficiency, device size, and cost built-in over–voltage and current-limiting protection prevent the CPU from damage. Power-good signal is sent when the core voltage is within ±10% of the setting point. The linear section is a low dropout regulator which drives low cost NPN transistors to supply the 1.5V and 2.5V regulated output power. Features Provides 3 Regulated Voltages N-MOSFET Power-good, Driver for High and Efficiency CurrentSwitching Section Over-voltage, limiting Protection for Switching Section 1.5V and 2.5V Fixed Output Voltage for Linear Section Linear Section Uses Low Cost NPN Transistor as Power Device TTL-compatible Voltage 5-bit DAC Core Output Applications Power Supply for Pentium, Pentium Pro Pentium II Alpha TM TM TM , , Power PC TM , K6 TM , 6×86 TM , and Microprocessors High-power 5V to 3.xV DC-DC Regulators Low-voltage Distributed Power Supplies Programmable Power Supplies Ordering Information RT9221 Package type S : SOP-24 Operating temperature range C: Commercial standard Pin Configurations Part Number RT9221CS (Plastic SOP-24) Pin Configurations TOP VIEW GND GATE1 LDOS1 LDOS2 1 2 3 4 5 GATE2 LDOV 22 VID0 24 23 21 20 19 18 17 16 15 14 13 VCC OVP 6 PGOOD 7 CSN 8 CSP 9 PGNDH 10 DH 11 PGNDL 12 VID1 VID2 VID3 VID4 VSEN SHDN BSTH BSTL DL DS9222-05 May 2001 www.richtek-ic.com.tw 1 RT9221 Absolute Maximum Ratings VCC to GND PGND to GND BSTH and BSTL to GND Ambient Temperature Range Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering, 10 sec.) Package Thermal Resistance SOP-24, θJA 75°C/W -0.3 to +5.5V ± 0.3V -0.3 to +14V 0 to +70°C 0 to +125°C -65 to +150°C 300°C Electrical Characteristics (VCC = 5V; GND = 0V; PGNDH = PGNDL = 0V; VSEN = VOUT; 0mV < (VCSP-VCSN) < 60mV; TA = 25°C) Parameter Switching Section Output Voltage Supply Voltage Supply Current Load Regulation Line Regulation Power On Reset Trip Point Current Limit Voltage Oscillator Frequency Oscillator Max Duty Cycle DH Source DH Sink DL Source DL Sink OVP Threshold Voltage OVP Source Current Power Good Threshold Voltage Linear Sections Quiescent Current Output Voltage (LDO1 RT9221) Output Voltage (LDO2 RT9221) Gain (AOL) Load Regulation Line Regulation Note: (1) See output voltage table. ∆VLINE LDOS (1,2) to GATE (1,2) ∆VLOAD IO = 0 to 5A LDOV = 11.4V to 12.6V IQ LDOV = 12V -2.450 1.470 ----2.500 1.500 65 1 1 5 2.550 1.530 ---mA V V dB % % IOVP VOVP = 3.0V VSEN Rising DMAX VBSTH - VDH = 1V VDH - VPGNDH = 1V VBSTH - VDL = 3V VDL - VPGNDL = 1V VLIMIT VOUT VCC ICC ∆VLOAD IO = 0.8A to 15A ∆VLINE VCC = 4.75V to 5.25V VCC Rising VCSP - VCSN IO = 2A VCC -4.5 ----65 170 90 ----114 10 87 (1) -3 1 0.5 4.2 75 200 95 3.5 3.5 2 2 120 ---5.5 6 ---85 230 -----122 -113 -V mA % % V mV KHz % Ω Ω Ω Ω % mA % Symbol Test Conditions Min Typ Max Units www.richtek-ic.com.tw DS9222-05 May 2001 2 RT9221 Function Block Diagram VCC CSN CSP + SHDN CURRENT LIMIT 70mV VID4 VID3 VID2 VID1 VID0 VSEN _ PGOOD + OPEN DRAIN 200KHz _ + + SHOOTTHROUGH CONTROL BSTL DRIVER + _ DL PGNDL DAC OSCILLATOR BSTH R Q S PGNDH LEVEL SHIFT AND DRIVER DH VCC _ ERROR AMP OVP LDOS1 GATE1 GND LINEAR CONTROLLER 2.5V 1.265V REF LINEAR CONTROLLER 1.5V + DS9222-05 May 2001 _ _ LDOV GATE2 LDOS2 GND www.richtek-ic.com.tw 1.25V REF 3 RT9221 Pin Description Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Pin Name GND GATE1 LDOS1 LDOS2 VCC OVP PGOOD CSN CSP PGNDH DH PGNDL DL BSTL BSTH SHDN VSEN VID4 VID3 VID2 VID1 VID0 (1) (1) (1) (1) (1) (1) (1) Pin Function Small signal analog and digital ground LDO1 gate drive output LDO1 sense input LDO2 sense input Input voltage High signal out if V0 > setting point + 20% Open collector logic output; High if V0 within 10% of the setting point Current sense input (Negative) Current sense input (Positive) High side drive GND High side drive output Low side drive GND Low side drive output Supply for low side driver Supply for high side driver Logic low shutdown the converter Top end of internal feedback chain Programming input (MSB) Programming input Programming input Programming input Programming input (LSB) +12V for LDO section LDO2 gate drive output LDOV GATE2 Note: (1) All logic level inputs and outputs are TTL compatible. www.richtek-ic.com.tw DS9222-05 May 2001 4 RT9221 Table 1 Output Voltage Program Test Output Voltage Conditions IO = 2A in application circuit VID 43210 01111 01110 01101 01100 01011 01010 01001 01000 00111 00110 00101 00100 00011 00010 00001 00000 11111 11110 11101 11100 11011 11010 11001 11000 10111 10110 10101 10100 10011 10010 10001 10000 Min 1.287 1.336 1.386 1.435 1.485 1.534 1.584 1.633 1.683 1.732 1.782 1.831 1.881 1.930 1.980 2.029 1.980 2.079 2.178 2.277 2.376 2.475 2.574 2.673 2.772 2.871 2.970 3.069 3.168 3.267 3.366 3.465 Typ 1.300 1.350 1.400 1.450 1.500 1.550 1.600 1.650 1.700 1.750 1.800 1.850 1.900 1.950 2.000 2.050 2.000 2.100 2.200 2.300 2.400 2.500 2.600 2.700 2.800 2.900 3.000 3.100 3.200 3.300 3.400 3.500 Max 1.313 1.364 1.414 1.465 1.515 1.566 1.616 1.667 1.717 1.768 1.818 1.869 1.919 1.970 2.020 2.071 2.020 2.121 2.222 2.323 2.424 2.525 2.626 2.727 2.828 2.929 3.030 3.131 3.232 3.333 3.434 3.535 Units V DS9222-05 May 2001 www.richtek-ic.com.tw 5 RT9221 Typical Application Circuit R13 12V 5V R14 10 10 C14 + R1 R2 C1 1µF 10K 10 0.1µF 5 VCC C2 CSP 9 1500µFx2 6 CSN 8 OVP 22 17 VID0 VSEN 21 7 VID1 PGOOD 20 18 VID2 VID4 19 15 VID3 BSTH 11 16 SHDN DH C4 1 10 GND PGNDH 0.1µF 12 13 PGNDL DL 24 14 GATE2 BSTL 23 2 GATE1 LDOV 4 LDOS2 LDOS1 3 RT9221 C13 1µF R3 10K C3 0.1µF R5 R4 1.0K 2.32K VID0 VID1 VID2 VID3 VID4 OVP SHDN + C5 Q2 PHB95N03LT 1500µFx4 PHB83N03LT Q1 R6 5mΩ L1 4µH VCC_CORE C6 0.1µF GND RFD3055 Q3 VLIN1 + C7 1000µF PGOOD R9 5Ω 5V 5V C9 1000µF R8 5Ω C8 0.1µF VLIN2 + C12 1000µF + +C10 1000µF Q4 RFD3055 C11 0.1µF www.richtek-ic.com.tw DS9222-05 May 2001 6 RT9221 Package Information H M B B J A C F D I Symbol A B C D F H I J M Dimensions In Millimeters Min 15.189 7.391 2.362 0.330 1.194 0.229 0.102 10.008 0.381 Max 15.596 7.595 2.642 0.508 1.346 0.330 0.305 10.643 1.270 Dimensions In Inches Min 0.598 0.291 0.093 0.013 0.047 0.009 0.004 0.394 0.015 Max 0.614 0.299 0.104 0.020 0.053 0.013 0.012 0.419 0.050 DS9222-05 May 2001 www.richtek-ic.com.tw 7 RT9221 RICHTEK TECHNOLOGY CORP. Headquarter 6F, No. 35, Hsintai Road, Chupei City Hsinchu, Taiwan, R.O.C. Tel: (8863)5510047 Fax: (8863)5537749 RICHTEK TECHNOLOGY CORP. Taipei Office (Marketing) 8F-1, No. 137, Lane 235, Paochiao Road, Hsintien City Taipei County, Taiwan, R.O.C. Tel: (8862)89191466 Fax: (8862)89191465 Email: marketing@richtek-ic.com.tw www.richtek-ic.com.tw DS9222-05 May 2001 8