XRP9710 Datasheet, PDF (27/36 Pages) Exar Corporation – Dual 6A Programmable Power Module

XRP9710 and XRP9711
Dual 6A Programmable Power Module
all channels if the supply drops to critical
levels.
• Over Temperature Protection (OTP)
monitors temperature of the chip and will
cause the controller to shut down all
channels if temperature rises to critical
levels.
• Over Voltage Protection (OVP)
monitors regulated voltage of a channel
and will cause the controller to react in a
user specified way if the regulated voltage
surpasses threshold level.
• Over Current Protection (OCP)
monitors current of a channel and will
cause the controller to react in a user
specified way if the current level
surpasses threshold level.
• Start-up Time-out Fault monitors
whether a channel gets into regulation in
a user defined time period
• LDO5 Over Current Protection (LDO5
OCP) monitors current drawn from the
regulator and will cause the controller to
be reset if the current exceeds LDO5 limit
warning level), the Low Vcc signal will
transition and the controller will be reset.
Special attention needs to be paid in the case
when Vcc = LDO5 = 4.75V to 5.5V. Since the
input voltage ADC resolution is 200mV, the
UVLO warning and fault set points are coarse
for a 5V input. Therefore, setting the warning
level at 4.8V and the fault level at 4.6V may
result in the outputs not being re-enabled
until a full 5.0V is reached on Vcc. Setting the
warning level to 4.6V and the fault level at
4.4V would likely make UVLO handing as
desired; however, at a fault level below 4.6V
the device has a hardware UVLO on LDO5 to
ensure proper shutdown of the internal
circuitry of the controller. This means the
4.4V UVLO fault level may never occur.
OTP
User defined OTP warning, fault and restart
levels are set at 5°C increments in PA 5.1.
UVLO
Both UVLO warning and fault levels are user
programmable and set at 200mV increments
in PA 5.1.
When the warning level is reached the
controller
will
generate
the
UVLO_WARNING_EVENT
interrupt.
In
addition, the host can be informed about the
event through HW Flags on GPIO0 (see the
Digital I/O section).
When an under voltage fault condition occurs,
the XRP9710/1 outputs are shut down and
the UVLO_FAULT_ACTIVE_EVENT interrupt is
generated. In addition, the host can be
informed by forwarding the Low Vcc signal to
any GPIO/PSIO (see the Digital I/O section).
This signal transitions when the UVLO fault
occurs. When coming out of the fault, rising
Vcc crossing the UVLO fault level will trigger
the UVLO_FAULT_INACTIVE_EVENT interrupt.
Once the UVLO condition clears (Vcc voltage
rises above or to the user-defined UVLO
When the warning level is reached the
controller
will
generate
the
TEMP_WARNING_EVENT
interrupt.
In
addition, the host can be informed about the
event through HW Flags on GPIO0 (see the
Digital I/O section).
When an OTP fault condition occurs, the
XRP9710/1 outputs are shut down and the
TEMP_OVER_EVENT interrupt is generated.
Once temperature reaches a user defined OTP
Restart
Threshold
level,
the
TEMP_UNDER_EVENT interrupt will be
generated and the controller will reset.
OVP
A user defined OVP fault level is set in PA 5.1
and is expressed in percentages of a
regulated target voltage.
Resolution is the same as for the target
voltage (expressed in percentages). The OVP
minimum and maximum values are calculated
© 2014 Exar Corporation
27/36
Rev. 1.0.1