MAX8550A
Description
The MAX8550A integrates a synchronous-buck PWM controller to generate VDDQ, a sourcing and sinking LDO linear regulator to generate VTT, and a 10mA reference output buffer to generate VTTR. The buck controller drives two external n-channel MOSFETs to generate output voltages down to 0.7V from a 2V to 28V input with output currents up to 15A.
Key Features
- The high bandwidth of this LDO regulator allows excellent transient response without the need for bulk capacitors, thus reducing cost and size. The buck controller and LDO regulators are provided with independent current limits. Adjustable lossless foldback current limit for the buck regulator is achieved by monitoring the drain-to-source voltage drop of the low-side MOSFET. Additionally, overvoltage and undervoltage protection mechanisms are built in. Once the overcurrent condition is removed, the regulator is allowed to enter soft-start again. This helps minimize power dissipation during a short-circuit condition. The MAX8550A allows flexible sequencing and standby power management using the SHDN and STBY inputs, which support all DDRs’ operating states. The MAX8550A is available in a small 5mm × 5mm, 28pin thin QFN package. Features Buck Controller
- Quick-PWM with 100ns Load-Step Response
- Up to 95% Efficiency * * * * * * * * * *
- 2V to 28V Input Voltage Range 1.8V/2.5V Fixed or 0.7V to 5.5V Adjustable Output Up to 600kHz Selectable Switching Frequency Programmable Current Limit with Foldback Capability 1.7ms Digital Soft-Start Independent Shutdown and Standby Controls Overvoltage/Undervoltage-Protection Option Power-Good Window Comparator LDO Section Fully Integrated VTT and VTTR Capability VTT Has ±3A Sourcing/Sinking Capability VTT and VTTR Outputs Track VREFIN / 2 MAX8550A
- All-Ceramic Output-Capacitor Designs
- 1.0V to 2.8V Input Voltage Range
- Power-Good Window Comparator
