The ADP1851 is a wide range input, dc-to-dc, synchronous
buck controller capable of running from commonly used 3.3 V
to 12 V (up to 20 V) voltage inputs. The device nominally
operates in current mode with valley current sensing providing
the fastest step response for digital loads. It can also be configured as a voltage mode controller with low noise and crosstalk
for sensitive loads.
The ADP1851 is ideal in system applications requiring multiple
output voltages. The ADP1851 includes a synchronization feature
to eliminate beat frequencies between switching devices. It also provides accurate tracking capability between supplies and
includes precision enable and power-good functions for simple, robust sequencing.
The ADP1851 provides a high speed, high peak current gate driving capability to enable energy efficient power conversion. The device can be configured to operate in power saving mode
by skipping pulses, reducing switching losses, and improving efficiency at light load and standby conditions.
The accurate current limit allows design within a narrower
range of tolerances and can reduce overall converter size and
cost. The ADP1851 can regulate down to 0.6 V output using a
high accuracy reference with ±1% tolerance over the
temperature range of −40°C to +125°C.
With its wide range input voltage, the ADP1851 provides the
designer with maximum flexibility for use in a variety of system
configurations; loop compensation, soft start, frequency setting, power saving mode, current limit, and current sense gain can
all be programmed using external components. In addition, the
external RAMP resistor allows the selection of optimal slope
and VIN feedforward in both current and voltage modes for excellent line rejection. The linear regulator and the bootstrap
diode for the high-side driver are internal.
Protection features include undervoltage lockout, overvoltage, overcurrent/short circuit, and overtemperature.
Applications
- Intermediate bus and POL systems requiring sequencing and tracking, including
- Telecom base station and networking
- Industrial and instrumentation
- Medical and healthcare
