JAJSHD6B August 2016 – May 2019 UCD90320
PRODUCTION DATA.
After rails are set up in the Pin Assignment tab, they are visible under the Vout Config tab, as shown in Figure 5. The initial voltage values are 0.
Configure the voltage monitoring parameters of the selected rail under the Vout Config tab. Figure 6 shows the configuration window..
When a AMON pin is assigned in Figure 4 to monitor the voltage of a particular a rail, a fault or warn event occurs when the monitored rail voltage exceeds the voltage window defined by the Over and Under Warn/Fault thresholds. When a fault is detected, the device responds with user-defined actions. See also the Fault Responses Configuration section for more details.
Rail Profile is composed of a group of nine thresholds set by: VOUT_COMMAND, VOUT_OV_FAULT_LIMIT, VOUT_OV_WARNING_LIMIT, VOUT_MARGIN_HIGH, POWER_GOOD_ON, VOUT_MARGIN_LOW, POWER_GOOD_OFF, VOUT_UV_WARNING_LIMIT and VOUT_UV_FAULT_LIMIT.
The device offers 50 individual profiles shared among all 24 AMON voltage rails. Each AMON voltage rail can have at least one but no more than 4 profiles. The profiles are controlled by 2 GPIs as shown in Figure 8. A programmable block-out period is used to block all voltage related faults on the given rail when profile is changed.
The device supports digital monitor. If a DMON pin is assigned in Figure 7 to monitor POWER_GOOD of POL. The DMON rail has no rail profile. If the DMON input is logic HIGH, the rail is POWER_GOOD, otherwise the rails has UV fault or warns and is at POWER_NOT_GOOD.
Vout Exponent defines the voltage value resolution according to PMBus linear data format. Fusion Digital Power Designer software can automatically select optimal Vout Exponent value to cover the required voltage range with the finest possible resolution. For more information regarding PMBus linear data format, refer to PMBus specification mentioned at the beginning of this section.
On/Off Config defines a rail turn-ON and turn-OFF command:
After receiving a turn ON or turn OFF command, a rail examines a series of conditions before asserting or de-asserting its EN pin. Conditions include Rail Sequence On/Off Dependency, GPI Sequence On/Off Dependency, Turn-On/Off Delay, as shown in Rail Sequence Configuration section.
Fixed percentage voltages setpoint, when checked, configures a rail into adaptive voltage scaling technology (AVS) mode. The Vout Setpoint can be dynamically set by PMBus during operation in order to achieve energy saving. The rail warn and fault voltage thresholds maintain fixed ratios with respect to the Vout Setpoint. Due to the fact that the power supply and UCD90320 device may not change Vout Setpoint simultaneously or with the same slew rate, the device takes the following steps to avoid false-triggering warn and fault. If the new Vout Setpoint is higher than the current Vout Setpoint , the OV warn and fault thresholds are immediately set to their respective new levels. Other thresholds are initially maintained, and then increase by 20-mV step size in every 400 µs until the new levels are reached. If the new Vout Setpoint is lower than the current Vout Setpoint, the UV warn and fault and Power Good On and Power Good Off thresholds are immediately set to their respective new levels. Other thresholds are initially maintained, and then decrease by 20-mV step size every 400 µs until the new levels are reached. Table 1 summarizes the thresholds adjustment scheme in AVS mode.. This feature is not available for DMON pin.
TRANSITION | IMMEDIATE UPDATE | ADJUSTMENT(1) |
---|---|---|
New Vout Setpoint to Current Vout Setpoint | OV fault and warn notification | UV fault and warn notification, Margin High and Margin Low, Power Good On and Power Good Off |
UV fault and warn notification, Power Good On and Power Good Off | OV fault and warn notification, Margin High and Margin Low, |
Current and temperature monitoring parameters of the selected rail can be configured under the Fault Responses and Limits tab. First select a rail in the top-right corner of the Fusion Digital Power Designer software , and then edit the current and temperature monitoring parameters as shown in Figure 10.
Each rail has a Power Good status determined by the following rules.
The Power Good status is not affected by any warnings and faults unless the fault response is to turn OFF the rail.
UV fault and warn notification is ignored when a rail is off. UV fault and warn notification is also ignored during start up until the rail enters Power Good status for the first time. This mechanism avoids false-triggering UV fault and warn notification when the rail voltage is expected to be below UV thresholds.
A Graceful Shutdown feature is enabled by checking the Configured as VIN Monitor checkbox. When enabled, the rail is configured to monitor VIN. When VIN drops below Power Good Off threshold, the device ignores any UV fault and warn notifications on any other rail.