The ADP1828 is a versatile and synchronous PWM voltage
mode buck controller. It drives an all N-channel power stage
to regulate an output voltage as low as 0.6 V to 85% of the input
voltage and is sized to handle large MOSFETs for point-of-load
regulators. The ADP1828 is ideal for a wide range of high power
applications, such as DSP and processor core I/O power, and
general-purpose power in telecommunications, medical imaging,
PC, gaming, and industrial applications. It operates from input
bias voltages of 3 V to 20 V with an internal LDO that generates
a 5 V output for input bias voltages greater than 5.5 V.
The ADP1828 operates at a pin-selectable, fixed switching
frequency of either 300 kHz or 600 kHz, or at any frequency
between 300 kHz and 600 kHz with a resistor. The switching
frequency can also be synchronized to an external clock up to
2× the part’s nominal oscillator frequency. The clock output can
be used for synchronizing additional ADP1828s (or the
ADP1829 controllers), thus eliminating the need for an external
clock source. The ADP1828 includes soft start protection to
limit any inrush current from the input supply during startup,
reverse current protection during soft start for a precharged
output, as well as a unique adjustable lossless current-limit
scheme utilizing external MOSFET RDSON sensing.
For applications requiring power-supply sequencing, the
ADP1828 provides a tracking input that allows the output
voltage to track during startup, shutdown, and faults. The
additional supervisory and control features include thermal
overload, undervoltage lockout, and power good.
The ADP1828 operates over the −40°C to +125°C junction
temperature range and is available in a 20-lead QSOP and 20-
lead, 4mm × 4mm LFCSP.
APPLICATIONS
- Telecom and networking systems
- Base station power
- Set-top boxes, game consoles
- Printers and copiers
- Medical imaging systems
- DSP and microprocessor core power supplies
- DDR termination
