www.fairchildsemi.com FAN5035 High Performance Programmable DC-DC Controller Features Description • Programmable output from 1.3V to 3.5V using an integrated 5-bit DAC • Remote sense • 1MHz operation • 85% efficiency typical at full load • Integrated Power Good and Enable/Soft Start functions • Uncommitted Op-amp • Drives N-channel MOSFETs • Over-current and over-voltage protection • 24 pin TSSOP package The FAN5035 is a voltage-mode DC-DC controller IC which provides a highly accurate, programmable output voltage for high-performance processors. The FAN5035 features remote voltage sensing, adjustable current limit and 1MHz operation. The FAN5035 uses a 5-bit D/A converter to program the output voltage from 1.3V to 3.5V. An on-board precision low TC reference achieves tight tolerance voltage regulation without expensive external components. The FAN5035 also offers integrated functions including Power Good, Output Enable/Soft Start, current limiting, over-voltage protection, and an uncommitted op-amp, and is available in a 24 pin TSSOP package. Applications • Power supply for Pentium® III • VRM for Pentium III processor • Programmable step-down power supply Block Diagram +5V VIN 14 9 VCC OVP 24 OSC 17 16 15 + 12 OUTA 13 GNDD A1 Digital Control 19 A3 20 18 + 21 + ISC 5-Bit DAC 1 2 3 4 5 VID0 VID2 VID4 VID1 VID3 Power Good OVP GNDA 22 10 OVP 8 VSENSE + 7 IFB 6 11 PWRGD 23 ENABLE/SS Pentium is a registered trademark of Intel Corporation. REV. 1.0.0 10/31/01 PRODUCT SPECIFICATION FAN5035 Pin Assignments D0 D1 D2 D3 D4 IFB_HI IFB_LO VSENSE VCC OVP PWRGOOD OUTA 1 2 3 4 5 6 7 8 9 10 11 12 FAN5035 24 23 22 21 20 19 18 17 16 15 14 13 COSC EN_SS GNDA VREF A3_INN A3_OUT A3_INP A1_OUT A1_INN A1_INP VIN GNDD Pin Definitions Pin Number Pin Name 1–5 D0-4 Voltage Identification Code Inputs. These open collector/TTL compatible inputs will program the output voltage over the ranges specified in Table 1. Pull-up resistors are internal to the controller. 6–7 IFB_HI IFB_LO Current Feedback. These pins are the input for the current feedback control loop. Layout of these traces is critical to system performance. 8 VSENSE 9 VCC Analog VCC. Connect to system 5V supply and decouple with a 0.1µF ceramic capacitor. 10 OVP Over-Voltage Protection. This pin drives an SCR when the output voltage is too high. 11 PWRGOOD 12 OUTA Output. Connect this pin to a driver for an N-channel MOSFET. The trace from this pin to the driver should be <0.5". 13 GNDD Power Ground. Return pin for high currents flowing in pin 12 (OUTA). Connect to a low impedance ground. 14 VIN 15–17 A1_INP A1_INN A1_OUT Uncommitted Op Amp. 18–20 A3_INP A3_INN A3_OUT Voltage Feedback Op Amp. This op amp is used for voltage feedback from the output, and for loop compensation. 21 VREF Reference Voltage. Decouple with a 0.1µF ceramic capacitor. 22 GNDA Analog Ground. Return path for low power analog circuitry. This pin should be connected to a low impedance system ground plane to minimize ground loops. 23 EN_SS Output Enable. A logic LOW on this pin will disable the output. An internal current source allows for open collector control. This pin also doubles as soft start. 24 COSC Oscillator Capacitor. Attach a capacitor from pin 24 to ground to set the oscillator frequency. 2 Pin Function Description Voltage Sense. Pin 8 is used as the input for Power Good and over-voltage protection. Power Good Flag. An open collector output that will be logic LOW if the output voltage is not within ±10% of the nominal output voltage setpoint. Input Voltage. Under-voltage detector input. REV. 1.0.0 10/31/01 FAN5035 PRODUCT SPECIFICATION Absolute Maximum Ratings Supply Voltage VCC 13V All Other Pins VCC Junction Temperature, TJ 150°C Storage Temperature -65 to 150°C Lead Soldering Temperature, 10 seconds 300°C Power Dissipation, PD 950mW Thermal Resistance Junction-to-case, ΘJC 16°C/W Recommended Operating Conditions Parameter Conditions Supply Voltage VCC Min. Typ. Max. Units 4.75 5 5.25 V VIN 3.3 Ambient Operating Temperature V 0 70 °C Electrical Specifications (VCC = 5V, VOUT = 2.0V, and TA = +25°C using circuit in Figure 1, unless otherwise noted.) The • denotes specifications which apply over the full operating temperature range Parameter Conditions Min. Typ. Max. Units Voltage Reference Output Voltage See Table I • 1.3 3.5 V Voltage Reference Accuracy VID4 = 0 VID4 = 1 • • -1.2 -1.6 1.2 1.6 % • 0 VCC–0.5 V • 180 324 nsec 900 1100 KHz 200 1500 KHz Current Feedback Current Feedback Input Range IFB Propagation Delay to OUTA 250 Oscillator Oscillator Frequency COSC=47pF Oscillator Frequency Range Oscillator Frequency TC • Oscillator Duty Cycle • 45 55 % Oscillator Ramp Amplitude • 0.75 0.9 1.05 VPP (Voscmax + Voscmin)/2 • 1.85 2.05 2.25 V 100pF Load • 49 72 nsec OUTA Fall Time 100pF Load • 60 80 nsec OUTA Voltage Low Isink = 20mA • 0.5 V OUTA Voltage High Isource = 20mA • VCC–1.1 A1 Output Current • 1.7 3 mA A1 Gain-Bandwidth • 11 15 MHz A1 Open Loop Gain • 50 55 dB A1 Slew Rate • 10 15 V/µsec Oscillator Ramp Mean 328 Hz/°C Output Driver OUTA Rise Time V A1 Amplifier REV. 1.0.0 10/31/01 3 PRODUCT SPECIFICATION FAN5035 Electrical Specifications (continued) (VCC = 5V, VOUT = 2.0V, and TA = +25°C using circuit in Figure 1, unless otherwise noted.) The • denotes specifications which apply over the full operating temperature range Parameter Conditions Min. Typ. Max. Units A1 Offset Voltage • 0.9 3 mV A1 Input Bias Current • 340 500 nA A1 Common Mode Input Range • -0.1 VCC–1.6 V • 0.9 VCC–0.95 V A3 Output Current • 1.7 3 mA A3 Gain-Bandwidth • 11 15 MHz A3 Open Loop Gain • 50 55 dB A3 Slew Rate • 10 A3 Offset Voltage • 0.9 3 mV A3 Input Bias Current • 340 500 nA A3 Common Mode Input Range • 0.25 VCC–0.98 V Voscmid + 0.8 V 14 KΩ A1 Output Voltage Swing Rload = 2KΩ to 2.5V A3 Amplifier 15 A3 Output Voltage Swing Rload = 2KΩ to 2.5V • 0.8 A3 Input Impedance INP to Ground • 9.33 11.67 D0-4 Pullup to VCC • 20 25 D0-4 Logic High • 2.1 D0-4 Logic Low • V/µsec VID Lines KΩ V 0.8 V 120 % Protection Over-voltage Protection VSENSE/VREF Over-voltage Hysteresis 112 115 • 1.2 3 % Over-voltage Output High No Load • VCC–0.2 Over-voltage Current VOVP = 3V • 40 50 0.5 V Output Low • 8 10 12 KΩ Short Circuit Threshold • 72 80 88 mV Short Circuit Threshold TC • 12 31 µV/°C VIN Input Impedance • 60 72 KΩ VIN UVLO Rising • 3.0 V VIN UVLO Falling • 2.5 VIN UVLO Hysteresis • 160 250 VSENSE Input Inpedance • 28 35 42 KΩ V • Over-voltage Output Low Over-voltage Input Impedance 4 • 48 mA V mV VSENSE Propagation Delay to OVP • 270 350 442 nsec VSENSE Propagation Delay to OUTA • 250 340 400 nsec 4.5 V VCC UVLO Rising • VCC UVLO Falling • 4.0 VCC UVLO Hysteresis • 160 V 250 mV REV. 1.0.0 10/31/01 FAN5035 PRODUCT SPECIFICATION Electrical Specifications (continued) (VCC = 5V, VOUT = 2.0V, and TA = +25°C using circuit in Figure 1, unless otherwise noted.) The • denotes specifications which apply over the full operating temperature range Parameter Conditions Min. Typ. Max. Units • 8 10 12 µA • -6 -5 -4 µA 80 %VCC Soft Start/Enable Soft Start Charge Current VEN_SS = 1V Soft Start Discharge Current Soft Start Pin Voltage 20 Power Good Power Good Output High 10KΩ Pullup • VCC – 0.1 Power Good Output Low 10KΩ Pullup • Power Good Sink Current VPG = 0.4V • 2.0 V 0.5 2.0 V mA Power Good High Threshold VSENSE/VREF • 106 111 % Power Good Low Threshold VSENSE/VREF • 89 94 % • 1.2 Power Good Threshold Hysteresis 2 % 60 nsec Power Good Rise Time 140 nsec Power Good Fall Time 15 nsec Power Good Propagation Delay VSENSE to PWRGOOD VCC Supply VCC Supply Current REV. 1.0.0 10/31/01 EN_SS and D0-4 open D0-4 grounded During soft-start • 16 17 22 22 mA 5 PRODUCT SPECIFICATION FAN5035 Table 1. Output Voltage Programming Codes VID4 VID3 VID2 VID1 VID0 Nominal VOUT 0 1 1 1 1 1.30V 0 1 1 1 0 1.35V 0 1 1 0 1 1.40V 0 1 1 0 0 1.45V 0 1 0 1 1 1.50V 0 1 0 1 0 1.55V 0 1 0 0 1 1.60V 0 1 0 0 0 1.65V 0 0 1 1 1 1.70V 0 0 1 1 0 1.75V 0 0 1 0 1 1.80V 0 0 1 0 0 1.85V 0 0 0 1 1 1.90V 0 0 0 1 0 1.95V 0 0 0 0 1 2.00V 0 0 0 0 0 2.05V 1 1 1 1 1 2.0V 1 1 1 1 0 2.1V 1 1 1 0 1 2.2V 1 1 1 0 0 2.3V 1 1 0 1 1 2.4V 1 1 0 1 0 2.5V 1 1 0 0 1 2.6V 1 1 0 0 0 2.7V 1 0 1 1 1 2.8V 1 0 1 1 0 2.9V 1 0 1 0 1 3.0V 1 0 1 0 0 3.1V 1 0 0 1 1 3.2V 1 0 0 1 0 3.3V 1 0 0 0 1 3.4V 1 0 0 0 0 3.5V Note: 0 = processor pin is tied to GND. 1 = processor pin is open. Test Parameters tR tF 90% 10% 6 90% OUTA 10% REV. 1.0.0 10/31/01 FAN5035 PRODUCT SPECIFICATION Mechanical Dimensions 24-Lead TSSOP Inches Symbol Min. A A1 B C D E e H L N α ccc Millimeters Max. Min. Notes: Notes Max. — .047 .002 .006 .007 .012 .004 .008 .303 .316 .169 .177 .026 BSC .252 BSC .018 .030 — 1.20 0.05 0.15 0.19 0.30 0.09 0.20 7.70 7.90 4.30 4.50 0.65 BSC 6.40 BSC 0.45 0.75 24 24 0° 8° 0° 8° — .004 — 0.10 1. Dimensioning and tolerancing per ANSI Y14.5M-1982. 2. "D" and "E" do not include mold flash. Mold flash or protrusions shall not exceed .006 inch (0.15mm). 3. "L" is the length of terminal for soldering to a substrate. 4. Terminal numbers are shown for reference only. 5. Symbol "N" is the maximum number of terminals. 2 2 3 5 D E H C A1 A B e SEATING PLANE –C– α L LEAD COPLANARITY ccc C REV. 1.0.0 10/31/01 7 PRODUCT SPECIFICATION FAN5035 Ordering Information Product Number Package FAN5035MTCX 24-pin TSSOP DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com 10/31/01 0.0m 000 Stock#DS30005035 2001 Fairchild Semiconductor Corporation