EZ1900

Features:

·  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


Application

·  Flexible upgrade from single voltage plane to split-plane processors
·  Intel Pentium® Processor P54CS & P55C upgrades
·  PowerPC™ 603 & 604 upgrades
·  AMD5K86™ upgrades


Pinout




Specifications

Parameter	Symbol	Maximum
Input Voltage Supply	VIN	7	V
Differential Amplifier	-IN, +IN SOUT	7 0 to +V	W
Slave Output Current (sink only)	ISLAVE	50	°C/W
Thermal Resistance Junction to Ambient	JA	160	°C/W
Operating Junction Temperature Range	TJ	0 to 70	°C
Storage Temperature Range	TSTG	-65 to 150	°C
Lead Temperature (Soldering) 10 Sec	TLEAD	260	°C

Description

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 EZ1900 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.