MAX5915EUI Maxim Integrated Products, MAX5915EUI Datasheet - Page 15

• Manufacturer Part Number: MAX5915EUI
• Description: Hot Swap & Power Distribution
• Manufacturer: Maxim Integrated Products

Specifications of MAX5915EUI

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Figure 3. Main and Auxiliary Supply Shutdown Control Logic for MAX5915/MAX5915A
The output voltages on all supplies, except the -12V
supply, are monitored for undervoltage. Output under-
voltage fault management is identical to the output
overcurrent fault management. Figures 5, 6, and 7 can
be used to illustrate undervoltage faults on the
MAX5915/MAX5915A/MAX5916/MAX5916A.
The MAX5915/MAX5915A/MAX5916/MAX5916A feature
internal thermal protection. Two thresholds detect when
the device is overheated. If the first threshold is reached,
the channel that is in overcurrent shuts down. If the sec-
ond thermal threshold is reached, the entire device shuts
down. The device cannot be restarted until the thermal
condition is cleared. For the MAX5915, the main chan-
nels turn back on after +12VIN or ON_ is toggled. For the
MAX5916, the main channels turn back on after
t
MAX5915A/MAX5916/MAX5916A restart after t
RESTART
STARTUP_3.3VAUXIN
SEE TABLE 2 FOR EXPLANATION OF SIGNALS.
ENABLE_3.3VAUXIN
STARTUP_+12VIN
ENABLE_+12VIN
OC_3.3VAUXO_
UV_3.3VAUXO_
OC_+12VO_
OC_-12VO_
UV_+12VO_
OC_3.3VO_
UV_3.3VO_
. The auxiliary channels for the MAX5915/
OC_5VO_
UV_5VO_
______________________________________________________________________________________
Thermal Shutdown Control
Output Undervoltage
Dual PCI 2.2 Hot-Swap Controllers
t
DELAY
t
DELAY
RESET
V
POSITIVE EDGE
TRIGGERED D FLIP-FLOP,
RESET IS ACTIVE LOW
RESTART
D
RESET
t
DELAY
Q
Q
.
V = INTERNAL SUPPLY LOGIC
GENERATED BY THE 12VIN OR THE
3.3VAUXIN, WHICHEVER IS HIGHER
t
RESTART
The MAX5915/MAX5915A/MAX5916/MAX5916A incor-
porate a PGOOD_ output to report when power is good
to a microprocessor or controller. PGOOD_ remains low
if the auxiliary outputs are not powered, for PCI and
compact PCI systems where the 3.3VAUX is not avail-
able. Connect 3.3VAUXIN to 3.3VIN and connect
AUXON_ to ON_ to allow PGOOD_ to transition high
when the main supplies are available. The open-drain
structure of PGOOD_ requires an external pullup resis-
tor (see the Functional Diagram). Figure 8 shows the
internal logic of the PGOOD_ output.
t
RESTART
POSITIVE EDGE TRIGGERED D FLIP-FLOP,
RESET IS ACTIVE LOW
V
D
RESET
PGOOD_ Operation
Q
Q
HIGH = MAIN SUPPLIES
HIGH = AUX SUPPLY
ARE TURNED OFF
TURNED OFF
MAIN ON
AUX OFF
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