XRP7714_1009 Datasheet, PDF (11/29 Pages) Exar Corporation – Quad Channel Digital PWM Step Down Controller

XRP7714
Quad Channel Digital PWM Step Down Controller
FEATURES AND BENEFITS
General DPWM Benefits:
• Eliminate temperature and time variations associated
with passive components in:
− Output set point
− Feedback compensation
− Frequency set point
− Under voltage lock out
− Input voltage measurement
− Gate drive dead time
• Tighter parameter tolerances including operating
frequency set point
• Easy configuration and re-configuration for different
Vout, Iout, Cout, and Inductor selection by simply
changing internal PID coefficients. No need to change
external passives for a new output specification.
• Higher integration: Many external circuits can be
handled by monitoring or modifying internal registers
• Selectable DPWM frequency and Controller Clock
Frequency
Other Benefits:
• A single voltage is needed for regulation [no External
LDO required].
• I²C interface allows:
− Communication with a System Controller or other
Power Management devices for optimized system
function
− Access to modify or read internal registers that
control or monitor:
− Output Current
− Input and Output Voltage
− Soft-Start/Soft-Stop Time
− ‘Power Good’
− Part Temperature
− Enable/Disable Outputs
− Over Current
− Over Voltage
− Temperature Faults
− Adjusting fault limits and disabling/enabling
faults
− Packet Error Checking (PEC) on I²C communication
• 6 Configurable GPIO pins, (4 if I²C is in use). Pins can
be configured in several ways:
− Fault reporting (including OCP, OVP, Temperature,
Soft-Start in progress, Power Good)
− Allows a Logic Level interface with other non-digital
IC’s or as logic inputs to other devices
− Possible to configure as traditional ‘enable’ pin for
all 4 outputs
− 2 GPIOs can be dedicated to the I²C Interface as
required by the customers design
• Frequency and Synchronization Capability
− Selectable switching frequency between 300kHz and
1.5MHz
− Channel to channel phase relationship is a fixed 90
degrees
− Main oscillator clock and DPWM clock can be
synchronized to external sources
− ‘Master’, ‘Slave’ and ‘Stand-alone’ Configurations
are possible
• Internal MOSFET Drivers
− Internal FET drivers (3Ω/6Ω) for each Channel
− Built-In Automatic Dead-time adjustment
− 30ns Rise and Fall times
• PowerArchitect™ Design and Configuration Software:
− In its simplest form only VIN, VOUT, and Iout for
each channel is required.
− The software calculates configuration register
content based upon customer requirements. PID
coefficients for correct loop response (for automatic
or customized designs) can be generated and sent
to the device.
− Configurations can be saved and/or recalled
− GPIOs can be configured easily and intuitively
− Synchronization configuration can be adjusted
− Interface can be used for real-time debugging and
optimization
• Customizing XRP7714 with customer parameters
− Once a configuration is finalized it can be sent to
EXAR and can reside in pre-programmed parts that
customers can order with an individual part number.
− Allows parts to be used without I²C interface
System Benefits:
• Reliability is enhanced via communication with the
system controller which can obtain real time data on
an output voltage, input voltage and current.
• System processors can communicate with the
XRP7714 directly to obtain data or make adjustments
to react to circuit conditions
• A system process or could also be configured to log
and analyze operating history, perform diagnostics and
if required, take the supply off-line after making other
system adjustments.
• If customer field service is a possibility for your end
product, parameter reporting and history would
provide additional capabilities for troubleshooting or
aid in future system upgrades.
© 2010 Exar Corporation
11/29
Rev. 1.1.4