ADP3153

5-Bit Digitally Programmable 1.8 V to 3.5 V Output Voltage Dual N-Channel Synchronous Driver Total Output Accuracy ±1% (0 to +70) High Efficiency Current-Mode Operation Short Circuit Protection Power Good Output Overvoltage Protection Crowbar On-Board Linear Regulator Controller VRM 8.2 Compatible Narrow Body TSSOP 20-Lead Package

Desktop PC Power Supply for: Pentium II Processor Deschutes Processor Pentium Pro Processor Pentium Processor AMDK6 Processor VRM Modules

Input Supply Voltage (Pin 15) . . . . . . . . . . . ....................... 0.3 V to +16 V
Shutdown Input Voltage . . . . . . . . . . . . . . . ....................... 0.3 V to +16 V
Power Dissipation . . . . . . . . . . . . . . . . . . . ....................... Internally Limited
Operating Temperature Range . . . . . . . . . . . . ..................... 0°C to +70°C
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . ...................... 150°C
JA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...........................110°C/W
Storage Temperature Range . . . . . . . . . . . . ...................65°C to +150°C
Lead Temperature Range (Soldering 10 sec) . . . . . . . ......................+300°C

*This is a stress rating only; operation beyond these limits can cause the device to be permanently damaged.

The ADP3153 is a highly efficient synchronous switching regulator controller and a linear regulator controller. The switching regulator controller is optimized for Pentium II and Deschutes
Processor applications where 5 V is stepped down to a digitally controlled output voltage between 1.8 V and 3.5 V. Using a 5-bit DAC to read a voltage identification (VID) code directly from
the processor, the ADP3153 uses a current mode constant offtime architecture to generate its precise output voltage.

The ADP3153 drives two N-channel MOSFETS in a synchronous rectified buck converter, at a maximum switching frequency of 250 kHz. Using the recommended loop compensation and guidelines, the ADP3153 provides a dc/dc converter that meets Intel's stringent transient specifications with a minimum number of output capacitors and smallest footprint. Additionally,
the current mode architecture also provides guaranteed short circuit protection and adjustable current limiting.

The ADP3153's linear regulator controller drives an external N-channel device. The output voltage is set by the ratio of the external feedback resistors. The controller has been designed for excellent load transient response.