The ADP1851ACPZ-R7 is a wide range input, dc-to-dc, synchronousbuck controller capable of running from commonly used 3.3 Vto 12 V (up to 20 V) voltage inputs. The device nominallyoperates in current mode with valley current sensing providingthe fastest step response for digital loads. It can also be configured as a voltage mode controller with low noise and crosstalkfor sensitive loads.
The ADP1851ACPZ-R7 is ideal in system applications requiring multipleoutput voltages. The ADP1851ACPZ-R7 includes a synchronization featureto eliminate beat frequencies between switching devices. It also provides accurate tracking capability between supplies andincludes precision enable and power-good functions for simple, robust sequencing.
The ADP1851ACPZ-R7 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 modeby skipping pulses, reducing switching losses, and improving efficiency at light load and standby conditions.
The accurate current limit allows design within a narrowerrange of tolerances and can reduce overall converter size andcost. The ADP1851ACPZ-R7 can regulate down to 0.6 V output using ahigh accuracy reference with ±1% tolerance over thetemperature range of −40°C to +125°C.
With its wide range input voltage, the ADP1851ACPZ-R7 provides thedesigner with maximum flexibility for use in a variety of systemconfigurations; loop compensation, soft start, frequency setting, power saving mode, current limit, and current sense gain canall be programmed using external components. In addition, theexternal RAMP resistor allows the selection of optimal slopeand VIN feedforward in both current and voltage modes for excellent line rejection. The linear regulator and the bootstrapdiode for the high-side driver are internal.
Protection features include undervoltage lockout, overvoltage, overcurrent/short circuit, and overtemperature.
Feature
- Input voltage range: 2.75 V to 20 V
- Output voltage range: 0.6 V to 90% VIN
- Maximum output current of more than 25 A
- Current mode architecture
- Configurable to voltage mode
- ±1% output voltage accuracy over temperature
- Voltage tracking
- Programmable frequency: 200 kHz to 1.5 MHz
- Synchronization input
- Power saving mode at light load
- Precision enable input
- Power good with internal pull-up resistor
- Adjustable soft start
- Programmable current sense gain
- Integrated bootstrap diode
- Starts into a precharged load
- Externally adjustable slope compensation
- Suitable for any output capacitor
- Overvoltage and overcurrent-limit protection
- Thermal overload protection
- Input undervoltage lockout (UVLO)
- Available in 16-lead, 4 mm × 4 mm LFCSP
- Supported by ADIsimPower design tool
Applications
- Intermediate bus and POL systems requiring sequencing and tracking, including
- Telecom base station and networking
- Industrial and instrumentation
- Medical and healthcare
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