MAX8717ETI+ Maxim Integrated Products, MAX8717ETI+ Datasheet - Page 15

• Manufacturer Part Number: MAX8717ETI+
• Description: IC CNTRLR PWR SUP 28-TQFN
• Manufacturer: Maxim Integrated Products

Specifications of MAX8717ETI+

• Applications: Controller, Notebook Computers
• Voltage - Input: 4 ~ 26 V
• Number Of Outputs: 2
• Voltage - Output: 3.3V, 5V, 1 ~ 5.5 V
• Operating Temperature: 0°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-TQFN Exposed Pad
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ON1 and ON2 provide independent control of output
soft-start and soft-shutdown. This allows flexible control
of startup and shutdown sequencing. The outputs can
be started simultaneously, sequentially, or indepen-
dently. To provide sequential startup, connect ON_ of
one regulator to PGOOD_ of the other. For example,
with ON1 connected to PGOOD2, OUT1 soft-starts after
OUT2 is in regulation. Drive ON_ low to clear the over-
voltage, undervoltage, and thermal fault latches.
Soft-start begins when ON_ is driven high and REF is in
regulation. During soft-start, the output is ramped up
Figure 2. Functional Diagram
Interleaved High-Efficiency, Dual Power-Supply
FSEL
SKIP1
ON1
ILIM1
CSH1
CSL1
BST1
DH1
LX1
V
DL1
FB1
PGOOD1
DD
PGND
MAX8717/MAX8756/MAX8757
SMPS Enable Controls (ON1, ON2)
______________________________________________________________________________________
OSC
Soft-Start and Soft-Shutdown
Controllers for Notebook Computers
(FIGURE 5)
DECODE
FB
FAULT PROTECTION
POWER-GOOD AND
CONTROLLER
(FIGURE 3)
PWM1
(FIGURE 7)
from 0V to the final set voltage in 2ms. This reduces
inrush current and provides a predictable ramp-up time
for power sequencing.
Soft-shutdown begins after ON_ goes low, an output
undervoltage fault occurs, or a thermal fault occurs.
The two outputs are independent. A fault at one output
does not trigger shutdown of the other. During soft-
shutdown the output is ramped down to 0V in 4ms,
reducing negative inductor currents that can cause
negative voltages on the output. At the end of soft-shut-
down, DL_ is driven high until startup is again triggered
by a rising edge of ON_. The reference is turned off
when both outputs have been shut down.
FAULT PROTECTION
POWER-GOOD AND
(FIGURE 7)
CONTROLLER
(FIGURE 3)
PWM2
(FIGURE 5)
DECODE
FB
V
DD
R
R
2.0V
REF
PGOOD2
GND
SKIP2
ILIM2
CSH2
CSL2
BST2
ON2
DH2
V
DL2
REF
LX2
FB2
CC
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