ADP1051
Preliminary Technical Data
THEORY OF OPERATION
The ADP1051 is designed as a flexible, easy-to-use, digital power
supply controller. The ADP1051 integrates the typical functions
that are needed to control a power supply such as:
• Output voltage sense and feedback
• Voltage feed forward control
• Digital loop filter compensation
• PWM generation
• Current, voltage, and temperature sense
• Housekeeping and I2C/PMBus interface
• Calibration and trimming
The main function of controlling the output voltage is performed
using the feedback ADCs, the digital loop filter, and the PWM
block.
The feedback ADCs use a multipath approach. There is a
combination of a high speed, low resolution (fast and coarse) ADC
and a low speed, high resolution (slow and accurate) ADC. The
ADC outputs combine to form a high speed and high resolution
feedback path. Loop compensation is implemented using the digital
filter. This PID (proportional, integral, derivative) filter is
implemented in the digital domain, allowing easy programming of
filter characteristics, which is of great value in customizing and
debugging designs. The PWM block generates up to six
programmable PWM outputs for control of FET drivers and
synchronous rectification FET drivers. This programmability
allows many traditional and specific switching topologies to be
realized.
Conventional power supply housekeeping features, such as remote
and local voltage sense and primary side current sense, are
included. An extensive set of protections are offered, including
overvoltage protection (OVP), over current protection (OCP), over
temperature protection (OTP), under voltage protection (UVP), SR
reverse current protection (RCP).
All these features are programmable through the I2C/PMBus
interface. This interface is also used for calibrations. Other
information, such as input current, output current, and fault flags,
is also available through this digital bus interface.
The internal EEPROM can store all programmed values and allows
standalone control without a microcontroller. A free, downloadable
ADP1051 GUI is available that provides all the necessary software
to program the ADP1051. To obtain the latest GUI software and a
user guide, visit http://www.analog.com/digitalpower.
The ADP1051 operates from a single 3.3V power supply and is
specified from -40°C to 125°C.
CS1
VF
CS2+ CS2-
VS+ VS-
1.2V 0.25V
VREF
OUTA
OUTB
OUTC
OUTD
SR1
SR2
PWM
ENGINE
DIGITAL CORE
8kB
EEPROM
PMBus
DAC
ADC
OSC
UVLO
LDO
OVP
RTD
ADD
RES
AGND
VDD
SYNI/FLGI SCL SDA
CTRL
PG/ALT#
Figure 13. Functional Block Diagram
VCORE
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