MAX8717ETI+ Maxim Integrated Products, MAX8717ETI+ Datasheet - Page 27

• 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

• Minimize current-sensing errors by connecting
• When trade-offs in trace lengths must be made, it is
• Route high-speed switching nodes (BST_, LX_, DH_,
1) Place the power components first, with ground ter-
2) Mount the controller IC adjacent to the low-side
Interleaved High-Efficiency, Dual Power-Supply
CSH_ and CSL_ directly across the current-sense
resistor (R
preferable to allow the inductor charging path to be
made longer than the discharge path. For example,
it is better to allow some extra distance between the
input capacitors and the high-side MOSFET than to
allow distance between the inductor and the low-
side MOSFET or between the inductor and the out-
put filter capacitor.
and DL_) away from sensitive analog areas (REF,
FB_, CSH_, CSL_).
minals adjacent (N
anode). If possible, make all these connections on
the top layer with wide, copper-filled areas.
MOSFET, preferably on the back side opposite N
and N
drive lines short and wide. The DL_ and DH_ gate
traces must be short and wide (50 mils to 100 mils
wide if the MOSFET is 1in from the controller IC) to
keep the driver impedance low and for proper adap-
tive dead-time sensing.
H_
to keep LX_, GND, DH_, and the DL_ gate-
SENSE_
______________________________________________________________________________________
).
L
_ source, C
Controllers for Notebook Computers
Layout Procedure
IN
, C
OUT
_, and D
L
L_
_
3) Group the gate-drive components (BST_ diode and
4) Make the DC-DC controller ground connections as
5) Connect the output power planes directly to the out-
TRANSISTOR COUNT: 5879
PROCESS: BiCMOS
capacitor and LDO5 bypass capacitor) together
near the controller IC.
shown in Figures 1 and 10. This diagram can be
viewed as having two separate ground planes:
power ground, where all the high-power compo-
nents go; and an analog ground plane for sensitive
analog components. The analog ground plane and
power ground plane must meet only at a single point
directly at the IC.
put filter capacitor positive and negative terminals
with multiple vias. Place the entire DC-DC converter
circuit as close to the load as is practical.
Chip Information
27