PROGRAMMABLE DC/DC CONTROLLER FOR ADVANCED MICROPROCESSORS SC1151 TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com March 11, 1998 DESCRIPTION FEATURES The SC1151 voltage mode controller contains most of the circuitry necessary to implement a DC/DC converter for powering advanced microprocessors such as Klamath, both in single and multiple processor configurations. • • • • The SC1151 features an integrated 5 bit D/A converter, pulse by pulse current limiting, integrated power good signaling, logic compatible shutdown and on-board over voltage protection (OVP). The SC1151 operates at a fixed frequency of 200kHz, providing an optimum compromise between size, efficiency and cost in the intended application areas. The integrated D/A converter provides programmability of output voltage from 2.0V to 3.5V in 100mV increments and 1.80V to 2.05V in 50mV increments with no external components. 85% efficiency 5 bit DAC for output programmability On chip power good and OVP functions Designed for Intel Klamath VRM8.1 requirements APPLICATIONS • • • • Klamath microprocessor supplies Klamath VRM modules 1.8V to 3.5V microprocessor supplies Programmable power supplies ORDERING INFORMATION (1) DEVICE SC1151CS PACKAGE TEMP RANGE (TJ) SO-16 0° to 125°C The SC1151 provides an OVP output which can be used to trigger a crowbar circuit for true over voltage protection. Note: (1) Add suffix ‘TR’ for tape and reel. BLOCK DIAGRAM ABSOLUTE MAXIMUM RATINGS VCC 1.25V REF CSm CURRENT LIMIT VCC - 70mV Parameter Symbol Maximum Units VCC to GND VIN -0.3 to 7 V ±1 V -0.3 to 15 V TA 0 to 70 °C TSTG -65 to +150 °C TLEAD 300 °C SHUTDOWN CSp BST + VID4 DECODED SHUTDOWN SIGNAL VID3 LEVEL SHIFT AND DRIVE D/A AND SHUTDOWN LOGIC VID2 DH R VID1 Q OSCILLATOR VID0 S PGND to GND PGND BST to GND VOSENSE + + + - - ERROR AMP PWRGOOD + VCC + - A17043A OVP GND Operating Temperature Range Storage Temperature Range Lead Temperature (Soldering) 10 sec PIN CONFIGURATION GND 1 16 VID0 VCC 2 15 VID1 OVP 3 14 VID2 PWRGOOD 4 13 VID3 CSm 5 12 VID4 CSp 6 11 VOSENSE PGND 7 10 DH 8 9 SHUTDOWN BST Pentium is a registered trademark of Intel Corporation © 1998 SEMTECH CORP. 1 652 MITCHELL ROAD NEWBURY PARK CA PROGRAMMABLE DC/DC CONTROLLER FOR ADVANCED MICROPROCESSORS SC1151 March 11, 1998 ELECTRICAL CHARACTERISTICS Unless specified: VCC = 4.75V to 5.25V; GND = PGND = 0V; VOSENSE = VO; 0mV < (CSp-CSm) < 60mV; TA = 25oC PARAMETER CONDITIONS VID MIN 43210 Output Voltage(2) IO = 2A in Application circuit 16935F TYP MAX 00101 1.782 1.800 1.818 UNITS V 00100 1.832 1.850 1.868 00011 1.881 1.900 1.919 00010 1.931 1.950 1.969 00001 1.980 2.000 2.020 00000 2.030 2.050 2.070 11111 1.980 2.000 2.020 11110 2.079 2.100 2.121 11101 2.178 2.200 2.222 11100 2.277 2.300 2.323 11011 2.376 2.400 2.424 11010 2.475 2.500 2.525 11001 2.574 2.600 2.626 11000 2.673 2.700 2.727 10111 2.772 2.800 2.828 10110 2.871 2.900 2.929 10101 2.970 3.000 3.030 10100 3.069 3.100 3.131 10011 3.168 3.200 3.232 10010 3.267 3.300 3.333 10001 3.366 3.400 3.434 10000 3.465 3.500 3.535 Load Regulation (1) xxxxx 1 % Line Regulation xxxxx 0.5 % UV Lockout xxxxx Current Limit Voltage xxxxx 60 Oscillator Frequency xxxxx Oscillator Max Duty Cycle DH Sink/Source Current Output Voltage Tempco IO = 0.3A to 13A BST - DH = 4.5V, DH - PGND = 2V 4.2 V 70 80 mV 180 200 220 kHz xxxxx 90 95 xxxxx 1 xxxxx % A 65 ppm/oC NOTES: (1) Low output currents, below the continuous conduction threshold will cause an increase in output voltage beyond the load regulation limit. For Application circuit 16935F see the regulation curve on sheet 5. (2) All VID codes not specifically listed here are invalid and cause shutdown exactly as if the shutdown pin had been asserted. xxxxx refers to any valid VID code. 2 © 1998 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA PROGRAMMABLE DC/DC CONTROLLER FOR ADVANCED MICROPROCESSORS SC1151 March 11, 1998 PIN DESCRIPTION Pin # Pin Name GND 1 2 VCC 3 OVP Chip Supply Voltage High Signal out if VO>setpoint + 20% 4 PWRGOOD 5 CSm 6 Pin Function Small Signal Analog and Digital Ground (1) CSp Open collector logic output, high if VO within 10% of setpoint GND 1 16 VID0 VCC 2 15 VID1 Current Sense Input (negative) OVP 3 14 VID2 PWRGOOD 4 13 VID3 CSm 5 12 VID4 Current Sense Input (positive) 7 PGND Power Ground CSp 6 11 VOSENSE 8 DH High Side Driver Output PGND 7 10 SHUTDOWN Vcc for High Side Driver DH 8 9 9 BST 10 SHUTDOWN 11 VOSENSE 12 13 14 15 16 (1) Logic low shuts down the converter Top end of internal feedback chain (1) Programming Input (MSB) (1) Programming Input (1) Programming Input (1) Programming Input (1) Programming Input (LSB) VID4 VID3 VID2 VID1 VID0 BST NOTE: (1) All logic level inputs and outputs are open collector TTL compatible 3 © 1998 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA PROGRAMMABLE DC/DC CONTROLLER FOR ADVANCED MICROPROCESSORS SC1151 March 11, 1998 APPLICATION CIRCUIT L1 4uH Q1 BUK556 5V IN R1 5mOhm C6 1000uF C8 1000uF C10 1000uF + + + + C3 1000uF C1 0.1uF + C2 1000uF + R2 10k D1 PSR16C30CT R5 10 C4 1000uF 12V IN R3 OVP 3 VID0 16 VID1 15 VID2 14 VID3 13 VID4 10 VCC CSp OVP CSm VID0 VOSENSE VID1 PWRGOOD VID2 VID4 VID3 BST SHUTDOWN 1 2.32k C11 0.1uF U1 2 VCCP GND DH PGND + + + C5 1000uF C7 1000uF C9 1000uF C12 0.1uF R4 1.00k 6 5 11 4 12 9 8 7 SHUTDOWN SC1151CS PWRGD REF 16935F C13 0.1uF MATERIALS LIST Quantity Reference Part/Description Vendor Notes 4 C1,C11-C13 0.1µF Ceramic Various 9 C2-C10 1000µF/6.3V SANYO 1 D1 PSR16C30CT PHOTRON 1 L1 4µH 1 Q1 BUK556 PHILIPS Logic level FET, ≤22mΩ, 30V 1 R1 5mΩ IRC OAR-1 Series 1 R2 10kΩ, 5%, 1/8W Various 1 R3 2.32kΩ, 1%, 1/8W Various 1 R4 1kΩ, 1%, 1/8W Various 1 R5 10Ω, 5%, 1/8W Various 1 U1 SC1151CS SEMTECH MV-GX or equiv. Low ESR 8 Turns 16AWG on MICROMETALS T50-52D core 4 © 1998 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA PROGRAMMABLE DC/DC CONTROLLER FOR ADVANCED MICROPROCESSORS SC1151 March 11, 1998 CHARACTERISTIC CURVES SC1151 Efficiency in Application circuit 16935F Application circuit 16935F Ripple, 3.1V, 10A out 100.0% 95.0% Efficiency 90.0% 3.50V Set 3.00V Set 85.0% 2.40V Set 80.0% 2.00V Set 75.0% 70.0% 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 Output Current (Amps) Application circuit 16935F Transient Response, 3.1V, 0.3A to 10A SC1151 Regulation in Application circuit 16935F Vo at Io=300mA steady state Vo at Io=10A steady state Steady state voltage levels are superimposed for reference. Voltage change (V) normalized at Io=2A 0.050 0.040 0.030 0.020 0.010 0.000 -0.010 -0.020 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 Output Current (Amps) 5 © 1998 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA PROGRAMMABLE DC/DC CONTROLLER FOR ADVANCED MICROPROCESSORS SC1151 March 11, 1998 OUTLINE DRAWING SO-16 LAND PATTERN SO-16 6 © 1998 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA