AD ADP1872

Synchronous Current-Mode with
Constant On-time, PWM Buck
Preliminary Technical Data
Power input voltage range: 2.7V to 20V
Bias supply voltage range: 2.7V to 5.5V
Minimum Output voltage 0.6V
1.0% Accuracy, 0.6V Reference Voltage
Supports all N-channel MOSFET power Stage
Available in 300 KHz, 600 KHz and 1.0 MHz
No Current Sense Resistor Required
Power saving mode under light loads
Resistor Programmable Current Sense Gain
Thermal overload protection
Short circuit protection
Precision Enable Input
Integrated boot strap diode for High Side Drive
180μA typical shutdown supply current
Starts into a pre-charged load
Small, 10-lead MSOP package
ADP1872 is well suited for a wide range of applications, from
Set Top Box design to Communication Infrastructure. The IC
can operate from a 2.7V to 5.5V supply but the power input can
be as high as 20V.
ADP1872 is available in three versions ADP1872A, ADP1872B
and ADP1872C with each version programmed respectively to
300KHz, 600KHz and 1MHz pseudo fixed frequency.
ADP1872 includes an internally fixed, soft start period to limit
input in-rush current from the input supply during startup and
reverse current protection during soft start for a pre-charged
output. The low-side current sense, current-gain scheme and
PSM / Forced PWM options reduces external part count and
improves efficiency.
Telecom and networking systems
Mid to High End servers
Set-top boxes
Medical imaging systems
DSP core power supplies
Rev. PrA
The ADP1872 is a versatile current mode synchronous stepdown controller. ADP1872 uses a constant ON-time, pseudo
fixed frequency with programmable Current Sense Gain
Current Control scheme for superior transient response,
optimal stability and current limit protection. It utilizes Valley
Current Mode Control architecture for optimum performance
at low Duty Cycles. It drives an all N-channel power stage to
regulate output voltages as low as 0.6V.
The ADP1872 operates over the –40°C to +125°C junction
temperature range and is available in a 10-pin MSOP package.
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rights of third parties that may result from its use. Specifications subject to change without notice. No
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