RC5040

The RC5040 is a synchronous mode DC-DC controller IC which provides an accurate, programmable output for Pentium Pro CPU applications. Using an integrated 4-bit DAC to accept a voltage identification (VID) code directly from the CPU, the RC5040 can generate precise output voltages between 2.1V and 3.5V in lO0mV increments. Output load currents in excess of 12A can be delivered using minimal external circuitry. The RC5040 is designed to operate in a standard PWM control mode under heavy load conditions and in PFM control mode while supplying light loads for optimal efliciency. An on-board precision low TC voltage reference eliminates the requirement for external components in order to achieve tight voltage regulation. The Pentium Pro CPU is continuously protected by an integrated Power Good function, which sends an active-low interrupt signal to the CPU in the event that the output voltage is out of tolerance. The internal oscillator can be programmed to operate over a range of 200KHz to lMHz to allow flexibility in choosing external components.

The features of RC5040 can be summarized as (1)programmable output from 2. 1V to 3.5V using integrated 4-bit DAC; (2)87% efficiency; (3)oscillator frequency adjustable from 200KHz to 1MHz; (4)on-chip power good and output enable functions; (5)excellent transient response; (6)over-voltage protection; (7)short circuit protection; (8)precision trimmed low TC voltage reference; (9)20 pin SOIC package; (10)meets intel pentium@ Pro VRM specifications using minimum number of external components.

The absolute maximum ratings of RC5040 are (1)supply voltages, VCCA, VCCD, VCCP:13V; (2)supply voltage for high side FET, VCCQP: 13V; (3)voltage identification code lnputs, VID3-VIDO: 13V; (4)junction temperature, TJ: 150°C; (5)storage temperature, TS: -65 to 150°C; (6)lead soldering temperature, 10 seconds 300°C.(Notes: 1. Functional operation under any of these conditions is not implied. Permanent damage may occur if the device is subject to conditions outside these ratings.