uPI Semiconductor UP1537PDDA

The uP1537 is a high-efficiency, single synchronous buck controller suitable for low output voltage point-of-load applications in notebook computers and similar digital consumer applications. The proprietary RCOTTM technology provides fast transient response and high noise immunity. It supports ceramic output capacitors. An advantage of this control scheme is that it does not require an external phase compensation network, helping the designer with ease-of-use and realizing low external component count configuration. This combination is ideal for building modern low duty ratio, ultra-fast load step response DC-DC converters. The output voltage ranges from 0.7V to 2.6V, and the conversion input voltage range is from 3V to 26V. The switching frequency is selectable from four preset values using a resistor connected from the RF pin to ground. RCOTTM control tracks the preset switching frequency over a wide range of input and output voltages, while it increases the switching frequency at stepup of load. The RF pin also serves in selecting between auto-skip mode and forced continuous conduction mode for light load conditions. The strong gate drivers of the uP1537 allow low RDS(ON) FETs for high current applications.

• Wide Input Voltage Range 3V ~ 26V
• Output Voltage Range 0.7V ~ 2.6V
• Build-in ±1% 0.7V Reference
• RCOTTM (Robust Constant On-Time) Control Architecture
• 4 Selectable Frequency Setting
• 4700ppm/OC RDS(ON) Currrent Sensing
• Internal 1ms Soft-start
• Pre-charged Start-up Capability
• Built-in Output Discharge
• Power OK Indication
• Over Voltage, Under Voltage, and Over Temperature Protection
• WDFN3x3-10L and WQFN2x2-12L package
• RoHS Compliant and Halogen Free

• Notebook Computers
• I/O Supplies
• System Power Supplies