MAX9111 Maxim, MAX9111 Datasheet - Page 8

• Manufacturer Part Number: MAX9111
• Description: The MAX9111/MAX9113 single/dual low-voltage differential signaling (LVDS) receivers are designed for high-speed applications requiring minimum power consumption, space, and noise
• Manufacturer: Maxim

Single/Dual LVDS Line Receivers with
Ultra-Low Pulse Skew in SOT23
__________ Applications Information
Bypass V
ic 0.1µF and 0.001µF capacitors in parallel, as close to
the device as possible, with the 0.001µF valued capaci-
tor the closest to the device. For additional supply
bypassing, place a 10µF tantalum or ceramic capacitor
at the point where power enters the circuit board.
Output trace characteristics affect the performance of
the MAX9111/MAX9113. Use controlled impedance
traces to match trace impedance to both transmission
medium impedance and the termination resistor.
Eliminate reflections and ensure that noise couples as
common mode by running the differential traces close
together. Reduce skew by matching the electrical
length of the traces. Excessive skew can result in a
degradation of magnetic field cancellation.
Maintain the distance between the differential traces to
avoid discontinuities in differential impedance. Avoid
90° turns and minimize the number of vias to further
prevent impedance discontinuities.
Transmission media should have a differential charac-
teristic impedance of about 100Ω. Use cables and con-
nectors that have matched impedance to minimize
impedance discontinuities.
Avoid the use of unbalanced cables such as ribbon or
simple coaxial cable. Balanced cables such as twisted
pair offer superior signal quality and tend to generate
less EMI due to canceling effects. Balanced cables
tend to pick up noise as common mode, which is
rejected by the LVDS receiver.
Figure 3a. Human Body ESD Test Modules
8
VOLTAGE
SOURCE
_______________________________________________________________________________________
HIGH-
DC
CC
CHARGE-CURRENT
LIMIT RESISTOR
with high-frequency surface-mount ceram-
1MΩ
R
100pF
C
C s
STORAGE
CAPACITOR
Cables and Connectors
RESISTANCE
DISCHARGE
1500Ω
R
D
Differential Traces
Supply Bypassing
DEVICE
UNDER
TEST
The MAX9111/MAX9113 input differential voltage
depends on the driver current and termination resis-
tance. Refer to the MAX9110/MAX9112 differential dri-
ver data sheet for this information.
Minimize the distance between the termination resistor
and receiver inputs. Use a single 1% to 2% surface-
mount resistor across the receiver inputs.
For LVDS applications, a four-layer PCB that provides
separate power, ground, LVDS signals, and input sig-
nals is recommended. Isolate the input and LVDS sig-
nals from each other to prevent coupling. For best
results, separate the input and LVDS signal planes with
the power and ground planes.
Figure 3b. Human Body Current Waveform
AMPERES
I
P
36.8%
100%
90%
10%
0
0
t
RL
CURRENT WAVEFORM
TIME
t
DL
I r
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
Board Layout
Termination