3.3V/5V/Adjustable-Output,
3.3V/5V/Adjustable-Output
Step-Up DC-DC Converters
MAX756/MAX757
PC Layout and Grounding
The MAX756/MAX757 high peak currents and high-fre-
quency operation make PC layout important for mini-
mizing ground bounce and noise. The distance
between the MAX756/MAX757’s GND pin and the
ground leads of C1 and C2 in Figure 1 must be kept to
less than 0.2" (5mm). All connections to the FB and LX
pins should also be kept as short as possible. To
obtain maximum output power and efficiency and mini-
mum output ripple voltage, use a ground plane and
solder the MAX756/MAX757 GND (pin 7) directly to the
ground plane.
___________________Chip Topography
SHDN
LX
3/5 (MAX756)
FB (MAX757)
GND
0.122"
(3.10mm)
REF
GND
OUT
LBI
LBO
0.080"
(2.03mm)
TRANSISTOR COUNT: 758
SUBSTRATE CONNECTED TO OUT
________________________________________________________Package Information
DIM
A
A1
B
C
D
E
e
H
h
L
α
INCHES
MAX
MIN
0.069
0.053
0.010
0.004
0.019
0.014
0.010
0.007
0.197
0.189
0.157
0.150
0.050 BSC
0.244
0.228
0.020
0.010
0.050
0.016
8˚
0˚
MILLIMETERS
MIN
MAX
1.35
1.75
0.10
0.25
0.35
0.49
0.19
0.25
4.80
5.00
3.80
4.00
1.27 BSC
5.80
6.20
0.25
0.50
0.40
1.27
0˚
8˚
21-325A
E
H
D
A
e
B
0.127mm
0.004in.
h x 45˚
α
A1
C
L
8-PIN PLASTIC
SMALL-OUTLINE
PACKAGE
8
_______________________________________________________________________________________
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
