RT9223CS

RT9223 5-Bit Programmable Synchronous PWM Buck Converter Controller General Description The RT9223 is a high efficiency synchronous switching regulator for modern CPU application. The output is controlled by a 5-bit DAC programmed from 1.3V to 2.05V in 0.05V steps and from 2.1V to 3.5V in 0.1V increments. The switching controller drivers two N-MOSFETs at 200KHz frequency and provides an optimal solution for size, efficiency and cost in any application circuits. The controller also offers integrated functions including PGOOD, output enable, overvoltage, internal digital-count soft start, and currentlimiting protection in one chip. Features High Efficiency Synchronous N-MOSFET Driver Operating at 200KHz 1.3V ~ 2.05V (0.05V steps) and 2.1V ~ 3.5V (0.1V steps) Output Voltage Enable Input, PGOOD Output, OVP, and Current-limiting Protection Internal Digital-count Soft Start Applications Power Supply for Pentium Pro K6 TM TM , PowerPC TM , , 6x86 TM , and Alpha TM Microprocessors High-power 5V to 3.xV DC-DC Regulators Low-voltage Distributed Power Supplies Programmable Step-down Power Supplies Ordering Information RT9223 Package type S : SOP-20 Operating temperature range C: Commercial standard Pin Configurations Part Number RT9223CS (Plastic SOP-20) Pin Configurations TOP VIEW GND 1 VCC 2 OVP 3 PGOOD CSN CSP PGNDH DH 4 5 6 7 8 20 19 18 17 16 15 14 13 12 11 VID0 VID1 VID2 VID3 VID4 VSEN SHDN BSTH BSTL DL NC 9 PGNDL 10 DS9223-07 May 2001 www.richtek-ic.com.tw 1 RT9223 Absolute Maximum Ratings VCC to GND PGND to GND BST to GND Ambient Temperature Range Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering, 10 sec.) Package Thermal Resistance SOP-20, θJA 87°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 Note: (1) See output voltage table. IOVP VOVP = 3.0V VSEN Rising DMAX VBSTH - VDH = 1V VDH - VPGNDH = 1V VBL - VDL = 5V 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 -4.3 ----65 170 90 ----114 10 87 (1) -2 1 0.5 4.2 75 200 95 4.5 3.5 1 2 120 ---5.5 5 ---85 230 -----122 -115 -V mA % % V mV KHz % Ω Ω A Ω % mA % Symbol Test Conditions Min Typ Max Units www.richtek-ic.com.tw DS9223-07 May 2001 2 RT9223 Function Block Diagram VCC CSN CSP SHDN CURRENT LIMIT 1.25V REF 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 + GND DS9223-07 May 2001 _ _ + www.richtek-ic.com.tw 3 RT9223 Pin Description Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Pin Name GND VCC OVP PGOOD CSN CSP PGNDH DH NC 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 Power supply input High signal out if VO > setting point +20% Open collector logic output; High if VO within 10% of the setting point Current sense input (Negative) Current sense input (Positive) High side drive GIND High side driver output No connection Low side drive GND Low side driver 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) Note: (1) All logic level inputs and outputs are TTL compatible. www.richtek-ic.com.tw DS9223-07 May 2001 4 RT9223 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 DS9223-07 May 2001 www.richtek-ic.com.tw 5 RT9223 Typical Application Circuit 5V IN C1 0.1µF R6 10 C7 1µF C2 1000µFx3 + R2 10K R5 10 Q1 Q2 L1 4µH R3 5mΩ + C3 1000µFx6 C4 0.1µF VOUT 1N5817 R3 R4 12V IN OVP VID0 VID1 VID2 VID3 VID4 VCC 3 OVP 20 VID0 19 VID1 18 VID2 17 14 1 10 C6 0.1µF 2 6 CSP 5 CSN 15 VSEN 4 PGOOD 16 VID4 13 VID3 BSTH 8 SHDN DH 7 GND PGNDH 11 DL PGNDL BSTL 12 NC RT9223 C5 0.1µF 2.32k 1.00k SHDN PGOOD www.richtek-ic.com.tw DS9223-07 May 2001 6 RT9223 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 12.598 7.391 2.362 0.330 1.194 0.229 0.102 10.008 0.381 Max 13.005 7.595 2.642 0.508 1.346 0.330 0.305 10.643 1.270 Dimensions In Inches Min 0.496 0.291 0.093 0.013 0.047 0.009 0.004 0.394 0.015 Max 0.512 0.299 0.104 0.020 0.053 0.013 0.012 0.419 0.050 DS9223-07 May 2001 www.richtek-ic.com.tw 7 RT9223 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 DS9223-07 May 2001 8