RT9227A-CS

Preliminary RT9227A Advanced PWM and Dual Fixed Linear Power Controller General Description The RT9227A is a 3-in-one power controller optimized for high-performance microprocessor and computer applications. The IC integrates a synchronous buck PWM controller, a linear regulator and a linear controller as well as monitoring and protection functions into a 24-pin SOP package. The PWM controller regulates the microprocessor core voltage. The linear regulator provides power for the clock driver circuit and the linear controller regulates power for the GTL bus. The RT9227A features an Intel-compatible, TTL 5-bit programmable DAC that adjusts the core voltage from 2.1V to 3.5V in 0.1V increments and from 1.3V to 2.05V in 0.05V steps. The 5-bit DAC has a typical ±1% tolerance. The linear regulator uses an internal drive device to provide a fixed 2.5V ±2.5% output voltage. The linear controller drives an external Nchannel MOSFET or a low cost NPN bipolar transistor to provide a fixed 1.5V ±2.5%. The RT9227A monitors all the output voltages. A Power-good signal is issued when the core voltage is within ±10% of the DAC setting and the other levels are above their under-voltage levels. Additional buildin over-voltage protection for the core output uses the lower MOSFET to prevent output voltage above 115% of the DAC setting. The PWM over-current function monitors the output current using the voltage drop across the upper MOSFET’s RDS(ON), which eliminates the need for a current sensing resistor. Features 3-in-one Regulated Voltages for Microprocessor Core, Clock, and GTL Compatible with HIP6016 Power-good Output Voltage Monitor Switching section 5-bit DAC Programmable from 1.3V to 3.5V ±1% DAC Accuracy Fast Transient Response Full 0% to 100% Duty Cycle Driver Fixed 200kHz Switching Frequency Adaptive Non-overlapping Gate Driver Over-current Monitor Uses MOSFET RDS(ON) Over-voltage Protection Uses Lower MOSFET Linear Section Fixed Linear Regulator Output Voltage MOSFET or NPN Driving Capability Ultra Fast Response Speed Under-voltage Protection Internal Thermal Shutdown Applications Full Motherboard Power Regulation for Computer Low-voltage Distributed Power Supplies Pin Configurations Part Number RT9227ACS (Plastic SOP-24) VCC VID4 VID3 VID2 VID1 VID0 PGOOD FAULT SS NC FB2 VIN2 Pin Configurations TOP VIEW 1 2 3 4 5 6 7 8 9 10 11 12 UGATE1 PHASE1 22 LGATE1 24 23 21 20 19 18 17 16 Ordering Information RT9227A Package type S : SOP-24 Operating temperature range C: Commercial standard PGND OCSET1 VSEN1 FB1 NC FB3 15 GATE3 14 GND 13 VOT2 DS9227A-02 July 2001 www.richtek-ic.com.tw 1 RT9227A Absolute Maximum Ratings Supply Voltage PGOOD and GATE Voltage Input, Output or I/O Voltage Ambient Temperature Range Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering, 10 sec.) Package Thermal Resistance SOP-24,θJA Preliminary +15V GND−0.3V to VCC+0.3V GND− 0.3V to 7V 0°C to +70°C 0°C to +125°C -65°C to +150°C 300°C 75°C/W Recommended Operating Conditions Supply Voltage Ambient Temperature Range J unction Temperature Range CAUTION: Stresses beyond the ratings specified in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. +12V±10% 0°C to 70°C 0°C to 125°C Electrical Characteristics (VCC = 12V, PGND = 0V, TA = 25°C, unless otherwise specified) Parameter VCC Supply Current Nominal Supply Current Power-On Reset VCC Rising Threshold VCC Falling Threshold Rising VIN2 Under-Voltage Threshold VIN2 Under-Voltage Hysteresis Rising VOCSET1 Threshold Oscillator Free Running Frequency Ramp Amplitude Reference and DAC DAC (VID0 – VID4) Input Low Voltage DAC (VID0 – VID4) Input High Voltage DACOUT Voltage Accuracy DACOUT Voltage Accuracy DACOUT = 2.05 ~ 3.50V DACOUT = 1.30 ~ 2.00V -2.0 -1 -1% ----0.8 -1 20mV V V % -∆VOSC 180 -200 1.9 225 -KHz VP-P VOCSET1 = 4.5V VOCSET1 = 4.5V 7.5 7 ------0.5 1.25 9.5 9 2.8 --V V V V V ICC UGATE1, GATE3, LGATE1, and VOUT2 Open -10 -mA Symbol Test Conditions Min Typ Max Units To be continued www.richtek-ic.com.tw DS9227A-02 July 2001 2 Preliminary Parameter Linear Regulator Regulation Voltage Under-Voltage Level Under-Voltage Hysteresis Over-Current Protection Over-Current Protection During Start-Up Linear Controller Regulation Voltage Under-Voltage Level Under-Voltage Hysteresis PWM Controller Error Amplifier DC Gain PWM Controller Gate Driver UGATE Source UGATE Sink LGATE Source LGATE Sink Protection VOUT1 Over-Voltage Trip FAULT Souring Current OCSET1 Current Source Soft-Start Current Power Good VOUT1 Upper Threshold VOUT1 Under Voltage VOUT1 Hysteresis (VSEN1 / DACOUT) PGOOD Voltage Low VSEN1 Rising VSEN1 Rising Upper/Lower Threshold VPGOOD IPGOOD = -4mA 108 89 ----2 -IOCSET ISS VSEN1 Rising VFAULT = 8V VOCSET1 = 4.5V VSS = 1V 112 10 170 -RUGATE1 VCC = 12V VCC - VUGATE1 = 1V VCC = 12V, VLGATE1 = 2V ----3 3 1 2 -65 VREG VSEN3 = GATE3 0 < IGATE3 < 20mA FB3 Rising 1.462 --VREG 10mA < IVOUT2 < 150mA FB2 Rising 2.437 --180 -Symbol Test Conditions Min RT9227A Typ 2.500 1.875 100 230 700 Max 2.563 2.175 ---Units V V mV mA mA 1.500 1.125 100 1.538 1.305 --- V V mV dB 7 7 -6 120 -230 -112 95 -0.5 Ω Ω A Ω % mA µA µA % % % V RUGATE1 VUGATE1 = 1V ILGATE1 RLGATE1 VLGATE1 = 1V 115 14 200 11 DS9227A-02 July 2001 www.richtek-ic.com.tw 3 RT9227A Function Block Diagram Preliminary VSEN1 OCSET1 200 µA VCC VSEN3 GATE3 VIN2 3.3V _ + 0.3V 110% _ + 90% LINEAR UNDER VOLTAGE POWER-ON RESET (POR) 3.3V + _ VOUT2 FB2 OC2 0.25A SOFT-START & FAULT LOGIC VCC 0V OC1 + FAULT + + DACOUT TTL D/A CONVERTER (DAC) 5V ERROR AMP COMPENSATION SS VID0 VID2 VID4 VID1 VID3 FB1 Functional Pin Description VCC (Pin 1) Provide a 12V bias supply for the IC to this pin. This pin also provides the gate bias charge for all the MOSFETs controlled by the IC. VID0, VID1, VID2, VID3, VID4 (Pin 6, 5, 4, 3, and 2) VIDO-4 are the input pins to the 5-bit DAC. The states of these five pins program the internal voltage reference, DACOUT. The level of DACOUT sets the core converter output voltage. It also sets the core PGOOD and OVP thresholds. Table 1 specifies the DACOUT voltage of 32 combinations of VID levels. PGOOD (Pin 7) PGOOD is an open collector output used to indicate the status of the output voltage. This pin is pulled low when the core output is not within ±10% of the DACOUT reference voltage and the other outputs are below their under-voltage thresholds. The PGOOD output is open for ‘11111’ VID codes that inhibit operation. See table 1. FAULT (Pin 8) This pin is low during normal operation, but it is pulled to about 8V (VCC = 12V) in the event of an over-voltage or over-current condition. SS (Pin 9) Connect a capacitor from this pin to ground. This capacitor, along with an internal 11µA (VSS >1V) current source, sets the soft-start interval of the converter. DS9227A-02 July 2001 www.richtek-ic.com.tw 4 _ 11µA _ _ _ 1.26V 115% LUV _ + UPPER DRIVE _ INHIBIT GATE CONTROL PWM LOGIC PWM COMP LOWER DRIVE VCC OSCILLATOR + _ + + _ PGOOD VCC UGATE1 + PHASE1 LGATE1 PGND GND Preliminary FB2 (Pin 11) Connect this pin to VOUT2 to set the linear regulator output voltage. VIN2 (Pin 12) This pin supplies power to the internal regulator. Connect this pin to a suitable 3.3V source. Additionally, this pin is used to monitor the 3.3V supply. If, following a startup cycle, the voltage drops below 2.55V (typically), the chip shuts down. A new soft-start cycle is initiated upon return of the 3.3V supply above the under-voltage threshold. VOUT2 (Pin 13) Output of the linear regulator. Supplies current up to 230mA. GND (Pin 14) Signal ground for the IC. All voltage levels are measured with respect to this pin. GATE3 (Pin 15) Connect this pin to the gate of an external MOSFET or the base of an NPN. This pin provides the drive for the linear controller’s pass transistor. FB3 (Pin 16) Connect this pin to VOUT3 to set the linear controller output voltage. FB (Pin 18) The FB1 pin is the inverting input of the error amplifier. VSEN1 (Pin 19) This pin is connected to the PWM converter’s output voltage. The PGOOD and OVP comparator circuits use this signal to report output voltage status and for over voltage protection. OCSET1 (Pin 20) Connect a resistor (ROCSET1) from this pin to the drain of the upper MOSFET. ROCSET1, an internal 200µA current source (IOCSET1), and the upper MOSFET on-resistance (RDS(ON)) set the PWM LGATE1 (Pin 22) RT9227A converter over-current (OC) trip point according to the following equation: IPEAK = IOCSET1×ROCSET1 RDS(ON) PGND (Pin 21) This is the power ground of UGATE1 and LGATE1. Tie the PWM converter’s lower MOSFET source to this pin. Connect LGATE1 to the PWM converter’s lower MOSFET gate. This pin provides the gate drive for the lower MOSFET. An over-current trip cycles the soft-start function. Sustaining an over-current for 2 soft-start intervals shuts down the controller. PHASE1 (Pin 23) Connect the PHASE1 pin to the PWM converter’s upper MOSFET source. This pin is used to monitor the voltage drop across the upper MOSFET for overcurrent protection. UGATE1 (Pin 24) Connect UGATE pin to the PWM converter’s upper MOSFET gate. This pin provides the gate drive for the upper MOSFET. DS9227A-02 July 2001 www.richtek-ic.com.tw 5 RT9227A Preliminary Table 1. VOUT1 Voltage Program Pin Name VID4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 VID3 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 VID2 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 0 0 0 0 VID1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 VID0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 Normal OUT1 Voltage DACOUT 1.30 1.35 1.40 1.45 1.50 1.55 1.60 1.65 1.70 1.75 1.80 1.85 1.90 1.95 2.00 2.05 INHIBIT 2.10 2.20 2.30 2.40 2.50 2.60 2.70 2.80 2.90 3.00 3.10 3.30 3.30 3.40 3.50 www.richtek-ic.com.tw DS9227A-02 July 2001 6 Preliminary Typical Application Circuit 12V 5V GND F1 15A L1 1µH C1-4 4x1000µF + C20 1µF 3.3V 12 + C8 1000µF Q3 RFD3055 V OUT3 1.5V + C9 1000µF V OUT2 2.5V + C10 270µF 6 VID0 5 VID1 4 VID2 3 VID3 2 VID4 15 16 VIN2 R1 10 C5-6 2x1µF C7 RT9227A 1000pF 1 R2 VCC 20 OCSET1 1.21k PGOOD 7 24 23 22 21 19 18 C11 R5 0.68µF 732K Q1 PHB83N03LT L2 POWERGOOD R3 10K + V OUT1 1.3 to 3.5V GATE3 FB3 UGATE1 PHASE1 LGATE1 PGND VSEN1 FB1 RT9227A 13 11 VOUT2 FB2 PHB95N03LT 3.5µH C13-19 Q2 7x1000µF R4 4.99K FAULT 8 GND 14 SS 9 C12 0.039µF DS9227A-02 July 2001 www.richtek-ic.com.tw 7 RT9227A Package Information Preliminary 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 www.richtek-ic.com.tw DS9227A-02 July 2001 8 Preliminary RT9227A DS9227A-02 July 2001 www.richtek-ic.com.tw 9 RT9227A Preliminary 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 DS9227A-02 July 2001 10