MAX9273GTL/V+ Maxim Integrated, MAX9273GTL/V+ Datasheet - Page 39

• Manufacturer Part Number: MAX9273GTL/V+
• Description: Serializers & Deserializers - Serdes 1.5Gbps 22-bit Coax/STP serializer
• Manufacturer: Maxim Integrated
• Type: Serializerr

Specifications of MAX9273GTL/V+

• Rohs: yes
• Data Rate: 1.5 Gbit/s
• Input Type: CMOS/LVCMOS
• Output Type: CML
• Number Of Inputs: 22
• Number Of Outputs: 1
• Operating Supply Voltage: 1.7 V to 3.6 V
• Operating Temperature Range: - 40 C to + 105 C
• Package / Case: TQFN-40 EP
• Maximum Operating Temperature: + 105 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT

The control and configuration inputs (except three-level
inputs) include a pulldown resistor to GND. External pull-
down resistors are not needed.
The I
resistor to provide a logic-high level. There are tradeoffs
between power dissipation and speed, and a compro-
mise may be required when choosing pullup resistor
values. Every device connected to the bus introduces
some capacitance even when the device is not in opera-
tion. I
mode, which is defined for data rates up to 400kbps (see
the I
table for details). To meet the fast-mode rise-time require-
ment, choose the pullup resistors so that rise time t
0.85 x R
recognized if the transition time becomes too slow. The
serializer supports I
to-I
AC-coupling isolates the receiver from DC voltages up
to the voltage rating of the capacitor. Capacitors at the
serializer output and at the deserializer input are needed
for proper link operation and to provide protection if
either end of the cable is shorted to battery. AC-coupling
blocks low-frequency ground shifts and low-frequency
common-mode noise.
Voltage droop and the digital sum variation (DSV) of trans-
mitted symbols cause signal transitions to start from dif-
ferent voltage levels. Because the transition time is fixed,
starting the signal transition from different voltage levels
causes timing jitter. The time constant for an AC-coupled
link needs to be chosen to reduce droop and jitter to an
acceptable level. The RC network for an AC-coupled link
consists of the CML/coax receiver termination resistor
(R
Table 14. Suggested Connectors and Cables for GMSL
Maxim Integrated
Rosenberger
JAE
Nissei
Rosenberger
TR
2
C mode) and 400kbps (I
), the CML/coax driver termination resistor (R
2
C specifications in the AC Electrical Characteristics
2
2
C specifies 300ns rise times (30% to 70%) for fast
C and UART open-drain lines require a pullup
PULLUP
SUPPLIER
Selection of AC-Coupling Capacitors
Choosing I
x C
BUS
2
C/UART rates up to 1Mbps (UART-
< 300ns. The waveforms are not
2
Internal Input Pulldowns
C/UART Pullup Resistors
2
C-to-I
22-Bit GMSL Serializer with Coax or
2
C mode).
D4S10A-40ML5-Z
59S2AX-400A5-Y
CONNECTOR
GT11L-2S
MX38-FF
AC-Coupling
R
TD
=
),
Table 13. Typical Power-Supply Currents
(Using Worst-Case Input Pattern)
and the series AC-coupling capacitors (C). The RC time
constant for four equal-value series capacitors is (C x
(R
transmission line impedance (usually 100I differential,
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 serializer uses an AVDD and DVDD of 1.7V to 1.9V.
All inputs and outputs, except for the serial output, derive
power from an IOVDD of 1.7V to 3.6V that scales with
IOVDD. Proper voltage-supply bypassing is essential for
high-frequency circuit stability.
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 characteristic
impedance of 50I (contact the factory for 75I operation).
Table 14
in the GMSL link.
TD
PCLK
(MHz)
F-2WME AWG28
+ R
25
50
A-BW-Lxxxxx
Dacar 538
Power-Supply Circuits and Bypassing
CABLE
RG174
TR
lists the suggested cables and connectors used
))/4. R
currents
TD
AVDD
(mA)
29.5
34.9
STP Cable Drive
and R
Cables and Connectors
TR
shown
are required to match the
Power-Supply Table
DVDD
(mA)
14.4
9.4
MAX9273
in
TYPE
Coax
Table
STP
STP
STP
the
13.
IOVDD
Electrical
(mA)
0.2
0.3
39