REGULATOR BALANCE CONTROLLER May 27, 1999 EZ1900 TEL:805-498-2111 FAX:805-498-3804 WEB:http://www.semtech.com DESCRIPTION FEATURES The EZ1900 is a high performance positive load current balancer designed for use in applications utilizing 2 regulators in parallel to achieve equal current sharing or identical current for each load. The regulator balance controller allows a flexible motherboard design to be made to cope with different processor configurations. The controller reads a logic level upgrade signal (denoted VCC2DET on the Intel P55C; similar on AMD, Cyrix and PowerPC microprocessors) to control the output voltage of two linear low dropout voltage regulators to the CPU core and I/O planes. In single-voltage plane configurations (VCC2DET floating), both regulators are set to the same output voltage (usually 3.3 - 3.5V) and are configured in masterslave mode. For split plane processors (VCC2DET low), the outputs of the two regulators are switched - the core voltage will be set to a nominal 2.5V while the I/O voltage will remain at 3.3V. The actual output voltages can be adjusted by means of resistors. The EZ1900 programmable current balancer is available in the popular SO-8 surface mount package. • • • • • • Current balance controller for regulators in parallel Slave and non-slave voltage modes Slave or non-slave mode computer selected Compatible with 3 or 5 pin low drop regulators Remote sense operation SO-8 package APPLICATIONS • • • • Flexible upgrade from single voltage plane to split-plane processors Intel Pentium® Processor P54CS & P55C upgrades PowerPC™ 603 & 604 upgrades AMD5K86™ upgrades ORDERING INFORMATION (1) DEVICE PACKAGE EZ1900CS SO-8 Note: (1) Add suffix ‘TR’ for tape and reel. PIN CONFIGURATION ABSOLUTE MAXIMUM RATINGS Parameter Input Voltage Supply Legend Description 1 Sel Non-slave mode, voltage select 2 -IN Negative error amplifier input 3 +IN Positive error amplifier input 4 -V Power input, common 5 nc No Connection 6 SOUT 7 +V Power input, positive 8 nc No connection Sets VOUT of slave device Units VIN 7 V -IN, +IN SOUT 7 0 to +V V Slave Output Current (sink only) ISLAVE 50 mA Thermal Resistance Junction to Ambient θJA 160 °C/W Operating Junction Temperature Range TJ 0 to 70 °C Storage Temperature Range TSTG -65 to 125 °C Lead Temperature (Soldering) 5 Sec TLEAD 260 °C Differential Amplifier Pin # Symbol Maximum Slave Mode Pin: For non “Computer Select Operation”, the Select Mode, pin #1, can be left open circuited for continuous slave mode operation or balance current control. Ground the Select Mode, pin #1, for non-slave mode operation. Pentium Processor is a trademark of Intel Corp. PowerPC is a trademark of IBM Corp. AMD5K86 is a trademark of Advanced Micro Devices. © 1999 SEMTECH CORP. 1 652 MITCHELL ROAD NEWBURY PARK CA 91320 REGULATOR BALANCE CONTROLLER EZ1900 May 27, 1999 ELECTRICAL CHARACTERISTICS Unless otherwise specified: VIN = 5V; ISLAVE = 10mA; TJ = 25°C. Test Conditions Parameter Symbol +V SOUT Test Limits TJ Min Typ Max Units 5 mV 7 V Input Input Error Voltage VIO Common Mode Input Range VCM Average Temperature Coefficient, Input DIFF Voltage ∆VIE ∆T 0.01 IIC 50 Common Mode Rejection Ratio CMRR Power Supply Rejection Ration Sensitivity Select Threshold Low High Select Input Current Low SEL = 0V 1 7V mV/°C 200 nA 70 80 dB PSRR 60 70 dB ∆IOUT / ∆VDIFF 10 50 VTH Ω Input Current 7V 0.8 V -200 µA 2.4 ISEL -150 High SEL = 7V 1 Output Slave Output Leakage SOL Slave Output Resistance RO 7V 2 1 µA 3 4 Ω 500 700 µA 3 5 mA 700 µA Power Supply Current Slave Mode Non-Slave Mode Off Mode ICC 2 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 REGULATOR BALANCE CONTROLLER EZ1900 May 27, 1999 VOUT/RESISTOR SELECTION REFERENCE (Resistor selection in Ω. See Typical Applications on following pages.) Slave Mode (Master Regulator) VM Non-Slave Mode (Slave Regulator) VS VOUT R3 R4 Calc VOUT VOUT R1 R2 *Calc VOUT 3.500 130 232 3.494 3.500 137 243 3.508 3.300 115 187 3.293 3.300 137 221 3.306 2.900 133 174 2.895 2.900 137 178 2.911 2.800 137 169 2.801 2.800 124 150 2.801 2.700 137 158 2.700 2.700 130 147 2.701 2.600 121 130 2.600 2.600 121 127 2.600 2.500 115 115 2.506 2.500 133 137 2.498 Notes: VM = VREF (1 + R4 / R3) + IADJ R4. Resistor selection is based upon standard table for 1% resistors. Notes: VS = VREF (1 + (R2 + 3Ω) / R1) + IADJ (R2 + 3Ω). *The EZ1900 operating in the non-slave mode operation will introduce approximately 3 ohms of resistance in the voltage set path when selected. The calculated values are based upon this addition. TYPICAL APPLICATIONS Balanced Current Controller Utilizing EZ108X/EZ158X Series Voltage Select Slave Mode Operation VM = VOUT of Master VM = VREF (1 + R4/R3) + IADJ R4 Non-Slave Mode, VS = VOUT of Slave VS = VREF (1 + (R2 + 3Ω) / R1) + IADJ (R2 + 3Ω) RSENSE Select RSENSE Select; Typical selection can be (50mV to 100mV) / (Total IOUT / 2). Trace resistance of 10mΩ and above can easily accomodate value required. 3 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 REGULATOR BALANCE CONTROLLER EZ1900 May 27, 1999 TYPICAL APPLICATIONS (cont.) Balanced Current Controller Utilizing EZ1087 Series Voltage Select Slave Mode Operation VM = VOUT of Master VM = VREF (1 + R4/R3) + IADJ R4 Non-Slave Mode, VS = VOUT of Slave VS = VREF (1 + (R2 + 3Ω) / R1) + IADJ (R2 + 3Ω) RSENSE Select RSENSE Select; Typical selection can be (50mV to 100mV) / (Total IOUT / 2). Trace resistance of 10mΩ and above can easily accomodate value required. Balanced Current Controller Utilizing EZ1580 Series Voltage Select Slave Mode Operation VM = VOUT of Master VM = VREF (1 + R4/R3) + IADJ R4 Non-Slave Mode, VS = VOUT of Slave VS = VREF (1 + (R2 + 3Ω) / R1) + IADJ (R2 + 3Ω) RSENSE Select RSENSE Select (100mV Min) / (Total IOUT / 2) The EZ1580 series requires RSENSE voltage to be less than 100mV. Trace resistance can easily accomodate value required. 4 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320 REGULATOR BALANCE CONTROLLER EZ1900 May 27, 1999 OUTLINE DRAWING SO-8 LAND PATTERN SO-8 5 © 1999 SEMTECH CORP. 652 MITCHELL ROAD NEWBURY PARK CA 91320