® PENTIUM PROCESSOR P55C VOLTAGE REGULATOR MODULE October 27, 1997 MP55C TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com DESCRIPTION: The MP54C/MP55C series of power modules are low noise (no EMI), economical linear DC:DC converters with an integral connector conforming to Intel Corporation’s Voltage Regulator Module specification for the Pentium® Processor. Outstanding features include internal current limiting and thermal shutdown, providing full device protection against load faults and thermal overstress. The MP55C is designed to power split voltage plane microprocessors requiring 3.3V VI/O and 2.xV VCORE. The VI/O is always supplied directly from a 3.3V input; either the main system power supply or a low dropout regulator on the motherboard. The CPU core can be supplied either from the 3.3V main supply to reduce heat dissipation (MP55C-3.3) or the 5V main power supply (MP55C-5). The MP55C-3.3 still requires a few mA of 5V power for control circuitry. The MP55C-3.3 will not be available for CPU core voltages higher than 2.8V. Please contact Semtech for availability. APPLICATIONS: • Pentium® Processor P55C, Cyrix 6x86 and AMD5K86 power supplies FEATURES: • Integral VRM header connector • Input voltage 5V ± 5% • 2.8 ± 0.1V output for CPU core power • 3.3V passes through the I/O power plane • Maximum output current 6A • Input power voltage: • 5V ± 5% for MP55C-5 or 3.3V for MP55C-3.3 Low noise, no EMI ORDERING INFORMATION: DEVICE Input (V) Output (V) MP55C-5-2.8 5.0 2.8 MP55C-5-2.5 5.0 2.5 MP55C-3.3-2.8 3.3 2.8 MP55C-3.3-2.7 3.3 2.7 MP55C-3.3-2.5 3.3 2.5 ELECTRICAL CHARACTERISTICS PARAMETER Output Voltage (1) Output Current Line Regulation(1) Load Regulation(1) Dropout voltage Current Surge Limit Quiescent Current Temperature Coefficient Temperature Stability RMS Output Noise(2) Ripple Rejection Ratio Linear Airflow Requirements (ambient temperature 55°C) 2.8V version 2.7V version 2.5V version (MP55C-5) (MP55C-3.3) SYMBOL VO MIN 2.7 2.6 2.4 IO REG(LINE) REG(LOAD) VD TYP 2.8 2.7 2.5 0.015 0.1 1.2 0.40 7.5 12 0.005 0.5 0.003 72 IS IQ TC TS VN RA 0.5 100 MAX 3.0 2.8 2.6 6.0 0.2 0.4 1.3 16 UNITS V A % % V A mA %/°C % %VO dB m/s ft/min NOTES: (1) Low duty cycle pulse testing with Kelvin connections required. (2) Bandwidth of 10 Hz to 10 kHz. Pentium is a registered trademark of Intel Corporation. AMD5K86 is a trademark of Advanced Micro Devices. 6x86 is a trademark of Cyrix. © 1997 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 ® PENTIUM PROCESSOR P55C VOLTAGE REGULATOR MODULE MP55C October 27, 1997 A INPUT AND OUTPUT CONNECTIONS Pin No. Row A Row B Pin No. 15 1 VSS VSS 1 14 2 VSS VSS 2 13 3 ND VI/O 3 12 4 VI/O VI/O 4 11 5 +3.3V +3.3V 5 10 6 +3.3V +3.3V 6 9 7 VCORE VCORE 7 8 8 VCORE VCORE 8 9 VSS VCORE 9 10 VCORE VCORE 10 11 PWR GOOD RES 11 12 SENSE DISABLE 12 13 VSS VSS 13 14 +5.0V +5.0V 14 15 +5.0V +5.0V 15 B 7 6 5 4 3 2 1 VRM PCB End view of VRM connector (viewed from motherboard side) VOLTAGE REGULATOR MODULE CONNECTOR PIN REFERENCE Pin Name +3.3V I/O Input Function +3.3V Supply +5.0V Input +5.0V Supply VCORE Output Voltage Regulator Module Output Notes Connected directly to VI/O. MP55C-3.3: Main Power Input MP55C-5: Main power input MP55C-3.3: Bias for regulator control 2.8V output for CPU core VI/O Output CPU I/O power connection. Tied to 3.3V input (VCC3) VSS Input Ground Reference Ground DISABLE Input Not connected PWR GOOD Output SENSE Input RES ND Input When driven high, this input will disable the Voltage Regulator Module output and the output of the module will float. Power Good is driven low when the VRM output is not within valid levels. Sense is provided for the regulator to correct for voltage drops across the connector and motherboard powerplane. Formerly UPVRM# © 1997 SEMTECH CORP. Not connected MP55C-5: Not connected MP55C-3.3: Connected Tied to output. Not connected 652 MITCHELL ROAD NEWBURY PARK CA 91320 ® PENTIUM PROCESSOR P55C VOLTAGE REGULATOR MODULE MP55C October 27, 1997 MECHANICAL DIMENSIONS Dimension Inches Millimeters A 2.575 65.4 B 1.8 45.7 C 0.8 20.3 D 1.6 40.6 E 0.24 6.1 B2 0.42 10.7 B3 0.15 3.8 B5 0.5 12.7 Component size and location for illustration only INPUT VOLTAGE CONFIGURATIONS MP55C-3.3 Uses 3.3V input (from main system power supply) for conversion to CPU core voltage. Lowest dropout at 4A is 0.35V; VCORE higher than 2.8V must use MP55C-5. MP55C-5 Uses 5V for main power and 3.3V for VI/O. 3.3V can be supplied by a low dropout regulator such as an EZ1085. 5V is supplied by main system power supply. A few milliamps of power at 5V is necessary for control circuit bias. © 1997 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320