MAX9272GTM/V+ Maxim Integrated, MAX9272GTM/V+ Datasheet - Page 39

• Manufacturer Part Number: MAX9272GTM/V+
• Description: Serializers & Deserializers - Serdes 1.5Gbps 28-bit Coax/STP deserializr
• Manufacturer: Maxim Integrated
• Type: Deserializerr

Specifications of MAX9272GTM/V+

• Rohs: yes
• Data Rate: 1.5 Gbit/s
• Input Type: CML
• Output Type: CMOS/LVCMOS
• Number Of Inputs: 1
• Number Of Outputs: 28
• Operating Supply Voltage: 1.7 V to 3.6 V
• Operating Temperature Range: - 40 C to + 105 C
• Package / Case: TQFN-48
• Maximum Operating Temperature: + 105 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT

(R
the series AC-coupling capacitors (C). The RC time con-
stant, for four equal-value series capacitors, is (C x (R
+ R
mission line impedance (usually 100I differential and
50I single-ended). This leaves the capacitor selection
to change the system time constant. Use 0.2FF or larger
high-frequency surface-mount ceramic capacitors, with
sufficient voltage rating to withstand a short to battery, to
pass the lower speed reverse control-channel signal. Use
capacitors with a case size less than 3.2mm x 1.6mm to
have lower parasitic effects to the high-speed signal.
The deserializer uses an AVDD and DVDD of 1.7V to
1.9V. All inputs and outputs, except for the serial input,
derive power from an IOVDD of 1.7V to 3.6V that scales
with IOVDD. Proper voltage-supply bypassing is essen-
tial for high-frequency circuit stability. The GPI-to-GPO
delay is 0.35ms (max). Keep the time between GPI trans-
missions to a minimum 0.35ms.
Power-supply
Characteristics table are the sum of the currents from
AVDD, DVDD, and IOVDD. Typical currents from the
individual power supplies are shown in
Interconnect for CML typically has a differential imped-
ance of 100I. Use cables and connectors that have
matched differential impedance to minimize impedance
discontinuities. Coax cables typically have a characteris-
tic impedance of 50I (contact the factory for 75I opera-
tion).
used in the GMSL link.
Separate the LVCMOS logic signals and CML/coax high-
speed signals to prevent crosstalk. Use a four-layer PCB
with separate layers for power, ground, CML/coax, and
LVCMOS logic signals. Layout PCB traces close to each
other for a 100I differential characteristic impedance.
Maxim Integrated
Table 14. Typical Power-Supply Currents
(Using Worst-Case Input Pattern)
TR
TR
PCLK
(MHz)
), the CML/coax driver termination resistor (R
Table 15
))/4. R
25
50
28-Bit GMSL Deserializer for Coax or STP Cable
Power-Supply Circuits and Bypassing
TD
lists the suggested cables and connectors
and R
currents
AVDD
(mA)
25.1
33.3
TR
are required to match the trans-
Cables and Connectors
shown
Power-Supply Table
DVDD
(mA)
13.7
9.2
in
Table
Board Layout
the
14.
IOVDD
Electrical
(mA)
10.3
13.3
TD
), and
TD
The trace dimensions depend on the type of trace used
(microstrip or stripline). Note that two 50I PCB traces
do not have 100I differential impedance when brought
close together—the impedance goes down when the
traces are brought closer. Use a 50I trace for the single-
ended output when driving coax.
Route the PCB traces for differential CML channel in par-
allel to maintain the differential characteristic impedance.
Avoid vias. Keep PCB traces that make up a differential
pair equal length to avoid skew within the differential pair.
ESD tolerance is rated for Human Body Model, IEC
61000-4-2, and ISO 10605. The ISO 10605 and IEC
61000-4-2 standards specify ESD tolerance for electronic
systems. The serial link inputs are rated for ISO 10605
ESD protection and IEC 61000-4-2 ESD protection. All
pins are tested for the Human Body Model. The Human
Body Model discharge components are C
R
components are C
The ISO 10605 discharge components are C
and R
Table 15. Suggested Connectors and
Cables for GMSL
Figure 32. Human Body Model ESD Test Circuit
Rosenberger
JAE
Nissei
Rosenberger
D
SUPPLIER
= 1.5kI
D
VOLTAGE
SOURCE
HIGH-
= 2kI
DC
(Figure
CHARGE-CURRENT-
(Figure
LIMIT RESISTOR
D4S10A-40ML5-Z
59S2AX-400A5-Y
CONNECTOR
S
GT11L-2S
MX38-FF
= 150pF and R
1MI
100pF
32). The IEC 61000-4-2 discharge
34).
C
S
RESISTANCE
DISCHARGE
STORAGE
CAPACITOR
1.5kI
R
D
MAX9272
A-BW-Lxxxxx
D
Dacar 538
F-2WME
= 330I
ESD Protection
CABLE
AWG28
RG174
S
= 100pF and
(Figure
DEVICE
UNDER
S
TEST
= 330pF
TYPE
Coax
STP
STP
STP
33).
39