ADP1046DC1-EVALZ Analog Devices, ADP1046DC1-EVALZ Datasheet - Page 23

• Manufacturer Part Number: ADP1046DC1-EVALZ
• Description: Daughter Cards & OEM Boards ADP1046 Daughter Card
• Manufacturer: Analog Devices
• Series: ADP1046r

Specifications of ADP1046DC1-EVALZ

• Rohs: yes
• Product: Daughter Cards
• Description/function: 100 kHz daughter board
• Interface Type: I2C
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Operating Supply Voltage: 3.3 V
• Factory Pack Quantity: 1
• For Use With: ADP1046

Data Sheet
OrFET Operation Examples
Hot Plug into a Live Bus
A new PSU is plugged into a live 12 V bus (yellow). The internal
voltage, VS1 (red), is ramped up before the OrFET is turned on.
After the OrFET is turned on (green), current in the new PSU
begins to flow to the load (blue). The turn-on voltage threshold
between the new PSU and the bus is programmable.
Runaway Master
A rogue PSU on the bus (yellow) has a fault condition, causing
the bus voltage to increase above the OVP threshold. The good
PSU turns off the OrFET (green) and regulates its internal volt-
age, VS1 (red). When the rogue power supply fault condition is
removed, the bus voltage decreases. The OrFET of the good PSU
is immediately turned on, and the good PSU resumes regulating
from VS3±.
Figure 26. Hot Plug into a Live Bus (Yellow Is Bus Voltage; Red Is VS1 Voltage;
Figure 27. Runaway Master (Yellow Is Bus Voltage; Red Is VS1 Voltage;
4
3
2
4
3
CH1 2.00V
CH3 2.00A
CH1 2.00V
CH3 2.00A
OrFET
Green Is OrFET Control Signal; Blue Is Load Current)
Green Is OrFET Control Signal; Blue Is Load Current)
VS1
CS2
CH2 2.00V
CH4 10.0V
CH2 2.00V
CH4 10.0V
OrFET
CS2
M10.0ms
M50.0ms
VS1
VS3
A CH4
A CH4
VS3
100mV
0mV
Rev. B | Page 23 of 92
Short Circuit
When one of the output rectifiers fails, the bus voltage can
collapse if the OrFET is not promptly turned off. The fast OrFET
comparator is used to protect the system from this fault event.
Figure 28 shows a short circuit applied to the output capacitors
before the OrFET. After the fast OrFET threshold for CS2± (blue)
is triggered, the OrFET (green) is turned off. Figure 28 also shows
the operation when the short circuit is removed. The internal
regulation point, VS1 (red), returns to 12 V, and the OrFET
(green) is reenabled. The PSU again begins to contribute
current to the load (blue).
Light Load Mode Operation
PSU 1 increases its voltage at light load from 12 V to 12.1 V
(yellow). Both PSU 1 and PSU 2 are CCM; therefore PSU 1
sources current and PSU 2 sinks current (blue). In PSU 2, the
OrFET control turns off the OrFET to prevent reverse current
from flowing. Note that the OrFET voltage (green) is solid during
this transition because PSU 1 and PSU 2 are in CCM mode.
Figure 28. Internal Short Circuit (Yellow Is Bus Voltage; Red Is VS1 Voltage;
Figure 29. Light Load Mode (Yellow Is Bus Voltage; Red Is VS1 Voltage;
4
3
4
3
CH1 2.00V
CH3 2.00A
CH1 2.00V
CH3 2.00A
Green Is OrFET Control Signal; Blue Is Load Current)
Green Is OrFET Control Signal; Blue Is Load Current)
CS2
OrFET
CH2 2.00V
CH4 10.0V
CH2 2.00V
CH4 10.0V
VS3
OrFET
VS1
VS1
CS2
M200.0ms
M5.0ms
A CH4
A CH4
VS3
ADP1046
7.5mV
8.3mV