19-3954; Rev 3; 2/09
IT
TION K
VALUA
E
BLE
AVAILA
21-Bit Deserializers with Programmable
Spread Spectrum and DC Balance
General Description
The MAX9242/MAX9244/MAX9246/MAX9254 deserialize
three LVDS serial-data inputs into 21 single-ended LVC-
MOS/ LVTTL outputs. A separate parallel-rate LVDS clock
provides the timing for deserialization. The MAX9242/
MAX9244/MAX9246/MAX9254 feature spread-spectrum
capability, allowing the output data and clock frequency
to spread over a specified range to reduce EMI. The sin-
gle-ended data and clock outputs are programmable for
a frequency spread of ±2%, ±4%, or no spread. The
spread-spectrum function is also available when the
MAX9242/MAX9244/MAX9246/MAX9254 operate in non-
DC-balanced mode. The modulation rate of the spread is
32kHz for a 33MHz LVDS clock input and scales linearly
with frequency. The single-ended outputs have a sepa-
rate supply, allowing +1.8V to +5V output logic levels.
The MAX9254 features high output drive current for both
data and clock outputs for faster transition times in the
presence of heavy capacitive loads.
The MAX9242/MAX9244/MAX9246/MAX9254 feature pro-
grammable DC balance, allowing isolation between a
serializer and deserializer using AC-coupling. The
MAX9242/MAX9244/MAX9246/MAX9254 operate with the
MAX9209/MAX9213 serializers and are available with a
rising-edge strobe (MAX9242) or falling-edge strobe
(MAX9244/MAX9246/MAX9254). The LVDS inputs meet
ISO 10605 ESD specifications with ±30kV Air-Gap
Discharge and ±6kV Contact Discharge ratings.
Features
♦
Programmable ±4%, ±2%, or OFF Spread-Spectrum
Output for Reduced EMI
♦
Programmable DC-Balanced or Non-DC-Balanced
Modes
♦
DC Balance Allows AC-Coupling for Wider Input
Common-Mode Voltage Range
♦
Spread Spectrum Operates in DC-Balanced or
Non-DC-Balanced Mode
♦
High Output Drive (MAX9254)
♦
π
/ 4 Deskew by Oversampling
(MAX9242/MAX9244/MAX9254)
♦
16MHz-to-34MHz (DC-Balanced) and 20MHz-to-
40MHz (Non-DC-Balanced) Operation
(MAX9242/MAX9244/MAX9254)
♦
6MHz-to-18MHz (DC-Balanced) and 8MHz-to-20MHz
(Non-DC-Balanced) Operation (MAX9246)
♦
Rising-Edge (MAX9242) or Falling-Edge
(MAX9244/MAX9246/MAX9254) Output Strobe
♦
High-Impedance Outputs when
PWRDWN
is Low
Allow Output Busing
♦
Separate Output Supply Allows Interface to +1.8V,
+2.5V, +3.3V, and +5V Logic
♦
LVDS Inputs Meet ISO 10605 ESD Protection at
±30kV Air-Gap Discharge and ±6kV Contact
Discharge
♦
LVDS Inputs Meet IEC 61000-4-2 Level 4 ESD
Protection at ±15kV Air-Gap Discharge and ±8kV
Contact Discharge
♦
LVDS Inputs Conform to ANSI TIA/EIA-644 Standard
♦
+3.3V Main Power Supply
MAX9242/MAX9244/MAX9246/MAX9254
Applications
Automotive Navigation Systems
Automotive DVD Entertainment Systems
Digital Copiers
Laser Printers
Ordering Information
PART
MAX9242EUM
MAX9242GUM
MAX9244EUM
MAX9244GUM
MAX9246EUM
MAX9246GUM
MAX9254EUM
TEMP RANGE
-40°C to +85°C
-40°C to +105°C
-40°C to +85°C
-40°C to +105°C
-40°C to +85°C
-40°C to +105°C
-40°C to +85°C
PIN-PACKAGE
48 TSSOP
48 TSSOP
48 TSSOP
48 TSSOP
48 TSSOP
48 TSSOP
48 TSSOP
Selector Guide
FREQUENCY RANGE
PART
STROBE
EDGE
Rising
Falling
Falling
Falling
OVER-
SAMPLING
Yes
Yes
No
Yes
NON-DC
BALANCE
(MHz)
20 to 40
20 to 40
8 to 20
20 to 40
DC
BALANCE
(MHz)
16 to 34
16 to 34
6 to 18
16 to 34
MAX9242
MAX9244
MAX9246
MAX9254
Devices are available in lead-free packaging. Specify lead free
by adding a
+
symbol at the end of the part number when
ordering.
Pin Configuration appears at end of data sheet.
1
________________________________________________________________
Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
21-Bit Deserializers with Programmable
Spread Spectrum and DC Balance
MAX9242/MAX9244/MAX9246/MAX9254
ABSOLUTE MAXIMUM RATINGS
(All voltages referenced to GND.)
V
CC
, LVDSV
CC
, PLLV
CC
.......................................-0.5V to +4.0V
V
CCO
......................................................................-0.5V to +6.0V
RxIN_, RxCLKIN_ ..................................................-0.5V to +4.0V
PWRDWN
..............................................................-0.5V to +6.0V
SSG, DCB...................................................-0.5V to (V
CC
+ 0.5V)
RxOUT_, RxCLKOUT ...............................-0.5V to (V
CCO
+ 0.5V)
Continuous Power Dissipation (T
A
= +70°C)
48-Pin TSSOP (derate 16mW/°C above +70°C) ........1282mW
ESD Protection
Human Body Model (R
D
= 1.5kΩ, C
S
= 100pF)
All Pins to GND .............................................................±2.5kV
IEC 61000-4-2 (R
D
= 330Ω, C
S
= 150pF)
LVDS Inputs to GND (Air-Gap Discharge).....................±15kV
LVDS Inputs to GND (Contact Discharge).......................±8kV
ISO 10605 (R
D
= 2.0kΩ, C
S
= 330pF)
LVDS Inputs to GND (Air-Gap Discharge).....................±30kV
LVDS Inputs to GND (Contact Discharge).......................±6kV
Operating Temperature Range .........................-40°C to +105°C
Storage Temperature Range .............................-65°C to +150°C
Junction Temperature ......................................................+150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(V
CC
= LVDSV
CC
= PLLV
CC
= +3.0V to +3.6V, V
CCO
= +3.0V to +5.5V,
PWRDWN
= high; SSG = high, open, or low; DCB = high or
low, differential input voltage |V
ID
| = 0.05V to 1.2V, input common-mode voltage V
CM
= |V
ID
/ 2| to 2.4V - |V
ID
/ 2|, unless otherwise
noted. Typical values are at V
CC
= V
CCO
= LVDSV
CC
= PLLV
CC
= +3.3V, |V
ID
| = 0.2V, V
CM
= +1.25V, T
A
= +25°C.) (Notes 1, 2)
PARAMETER
POWER SUPPLY
Power-Supply Range
Output-Supply Range
V
CC
,
LVDSV
CC
,
PLLV
CC
V
CCO
DC-balanced
mode (SSG = low)
C
L
= 8pF,
worst-case pattern,
V
CC
= V
CCO
= 3.0V
to 3.6V, Figure 2
(MAX9242,
MAX9244,
MAX9254)
Non-DC-balanced
mode (SSG = low)
16MHz
34MHz
20MHz
33MHz
40MHz
DC-balanced mode 16MHz
(SSG = high or open) 34MHz
20MHz
Non-DC-balanced
33MHz
mode
(SSG = high or open) 40MHz
3.0
1.8
50
81
55
75
83
62
101
67
93
107
3.6
5.5
68
108
73
97
110
85
135
91
123
134
mA
V
V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Worst-Case Supply Current
I
CCW
2
_______________________________________________________________________________________
21-Bit Deserializers with Programmable
Spread Spectrum and DC Balance
DC ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= LVDSV
CC
= PLLV
CC
= +3.0V to +3.6V, V
CCO
= +3.0V to +5.5V,
PWRDWN
= high; SSG = high, open, or low; DCB = high or
low, differential input voltage |V
ID
| = 0.05V to 1.2V, input common-mode voltage V
CM
= |V
ID
/ 2| to 2.4V - |V
ID
/ 2|, unless otherwise
noted. Typical values are at V
CC
= V
CCO
= LVDSV
CC
= PLLV
CC
= +3.3V, |V
ID
| = 0.2V, V
CM
= +1.25V, T
A
= +25°C.) (Notes 1, 2)
PARAMETER
SYMBOL
CONDITIONS
6MHz
DC-balanced
mode (SSG = low)
8MHz
18MHz
8MHz
C
L
= 8pF,
worst-case pattern,
V
CC
= V
CCO
= 3.0V
to 3.6V, Figure 2
DC-balanced mode
(MAX9246)
(SSG = high or open)
Non-DC-balanced
mode
(SSG = high or open)
Power-Down Supply Current
High-Level Input Voltage
Low-Level Input Voltage
Input Current
Input Clamp Voltage
I
CCZ
V
IH
V
IL
I
IN
V
CL
PWRDWN
= high or low level
I
CL
= -18mA
PWRDWN
= low
2.0
-0.3
-20
-1.5
V
CC
+
0.3
+10
+0.8
+20
Non-DC-balanced
mode (SSG = low)
10MHz
20MHz
6MHz
8MHz
18MHz
8MHz
10MHz
20MHz
MIN
TYP
29
33
48
33
37
52
37
41
65
41
46
66
MAX
45
49
69
47
52
73
54
62
91
58
65
92
50
5.5
+0.8
+20
µA
V
V
µA
V
mA
UNITS
MAX9242/MAX9244/MAX9246/MAX9254
Worst-Case Supply Current
I
CCW
5V-TOLERANT LOGIC INPUT (PWRDWN)
THREE-LEVEL LOGIC INPUTS (DCB, SSG)
High-Level Input Voltage
Mid-Level Input Current
Low-Level Input Voltage
Input Current
Input Clamp Voltage
V
IH
I
IM
V
IL
I
IN
V
CL
DCB, SSG = high or low level,
PWRDWN
= high or low
I
CL
= -18mA
DCB, SSG open or connected to a driver with
output in high-impedance state (Note 3)
2.5
-10
-0.3
-20
-1.5
V
CCO
- 0.1
RxCLKOUT (Note 4)
High-Level Output Voltage
V
OH
I
OH
= -2mA
RxOUT_
MAX9254
I
OL
= 100µA
Low-Level Output Voltage
V
OL
RxCLKOUT (Note 4)
I
OL
= 2mA
RxOUT_
MAX9254
V
CCO
- 0.25
V
CCO
- 0.43
V
CCO
- 0.25
0.1
0.2
0.26
0.2
V
µA
V
µA
V
SINGLE-ENDED OUTPUTS (RxOUT_, RxCLKOUT)
I
OH
= -100µA
V
V
_______________________________________________________________________________________
3
21-Bit Deserializers with Programmable
Spread Spectrum and DC Balance
MAX9242/MAX9244/MAX9246/MAX9254
DC ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= LVDSV
CC
= PLLV
CC
= +3.0V to +3.6V, V
CCO
= +3.0V to +5.5V,
PWRDWN
= high; SSG = high, open, or low; DCB = high or
low, differential input voltage |V
ID
| = 0.05V to 1.2V, input common-mode voltage V
CM
= |V
ID
/ 2| to 2.4V - |V
ID
/ 2|, unless otherwise
noted. Typical values are at V
CC
= V
CCO
= LVDSV
CC
= PLLV
CC
= +3.3V, |V
ID
| = 0.2V, V
CM
= +1.25V, T
A
= +25°C.) (Notes 1, 2)
PARAMETER
High-Impedance Output Current
Output Short-Circuit Current
(Note 5)
SYMBOL
I
OZ
CONDITIONS
PWRDWN
= low, V
OUT
= -0.3V to (V
CCO
+ 0.3V)
V
CCO
= 3.0V to 3.6V,
V
OUT
= 0V
VCCO = 4.5V to 5.5V,
VOUT = 0V
V
CCO
= 3.0V to 3.6V,
V
OUT
= 0V
VCCO = 4.5V to 5.5V,
VOUT = 0V
(Note 6)
(Note 6)
PWRDWN
= high or low
PWRDWN
= high or low,
V
CC
= V
CCO
= 0V or open,
Figure 1
PWRDWN
= high or low,
V
CC
= V
CCO
= 0V or open,
Figure 1
-40°C to +85°C
-40°C to +105°C
-40°C to +85°C
-40°C to +105°C
-50
-25
-40
42
42
246
246
+25
+40
78
kΩ
85
410
kΩ
440
RxCLKOUT (Note 4)
RxOUT_
RxCLKOUT (Note 4)
RxOUT_
RxOUT_
RxCLKOUT (Note 4)
RxOUT_
RxCLKOUT (Note 4)
MIN
-30
-10
-5
-28
-13
-16
-34
TYP
MAX
+30
-40
-20
-75
-37
-51
mA
-93
mA
UNITS
µA
I
OS
Output Short-Circuit Current
(MAX9254) (Note 5)
LVDS INPUTS (RxIN_, RxCLKIN_)
Differential Input High Threshold
Differential Input Low Threshold
Input Current
Power-Off Input Current
Input Resistor 1
I
OS
V
TH
V
TL
I
IN+
, I
IN-
50
mV
mV
µA
µA
I
INO+
, I
INO-
V
CC
= V
CCO
= 0V or open
R
IN1
Input Resistor 2
R
IN2
AC ELECTRICAL CHARACTERISTICS
(V
CC
= LVDSV
CC
= PLLV
CC
= +3.0V to +3.6V, V
CCO
= +3.0V to +3.6V, C
L
= 8pF,
PWRDWN
= high; SSG = high, open, or low;
DCB = high or low, differential input voltage |V
ID
| = 0.1V to 1.2V, input common-mode voltage V
CM
= |V
ID
/ 2| to 2.4V - |V
ID
/ 2|, unless
otherwise noted. Typical values are at V
CC
= V
CCO
= LVDSV
CC
= PLLV
CC
= +3.3V, |V
ID
| = 0.2V, V
CM
= +1.25V, T
A
= +25°C.) (Notes 6, 7, 8)
PARAMETER
Output Rise Time
Output Fall Time
Output Rise Time (MAX9254)
Output Fall Time (MAX9254)
SYMBOL
CLHT
CHLT
CLHT
CHLT
CONDITIONS
0.1 x V
CCO
to 0.9 x V
CCO
,
Figure 3
0.9 x V
CCO
to 0.1 x V
CCO
,
Figure 3
0.1 x V
CCO
to 0.9 x V
CCO
,
Figure 3
0.9 x V
CCO
to 0.1 x V
CCO
,
Figure 3
DC-balanced mode,
Figure 4
RxIN Skew Margin (Note 9)
RSKM
RxOUT_
RxCLKOUT
RxOUT_
RxCLKOUT
RxOUT_
RxCLKOUT
16MHz
34MHz
MIN
2.9
2.0
2.1
1.10
1.4
1.1
2560
900
2500
960
TYP
4.7
3.3
3.0
1.94
2.2
1.8
3142
1386
3164
1371
ps
MAX
6.5
4.1
4.2
2.70
3.3
2.8
UNITS
ns
ns
ns
ns
Non-DC-balanced mode, 20MHz
Figure 4
40MHz
4
_______________________________________________________________________________________
21-Bit Deserializers with Programmable
Spread Spectrum and DC Balance
AC ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= LVDSV
CC
= PLLV
CC
= +3.0V to +3.6V, V
CCO
= +3.0V to +3.6V, C
L
= 8pF,
PWRDWN
= high; SSG = high, open, or low;
DCB = high or low, differential input voltage |V
ID
| = 0.1V to 1.2V, input common-mode voltage V
CM
= |V
ID
/ 2| to 2.4V - |V
ID
/ 2|, unless
otherwise noted. Typical values are at V
CC
= V
CCO
= LVDSV
CC
= PLLV
CC
= +3.3V, |V
ID
| = 0.2V, V
CM
= +1.25V, T
A
= +25°C.) (Notes 6, 7, 8)
PARAMETER
RxCLKOUT High Time
RxCLKOUT Low Time
RxOUT Setup to RxCLKOUT
RxOUT Hold from RxCLKOUT
RxCLKIN to RxCLKOUT Delay
Deserializer Phase-Locked-
Loop Set
Deserializer Power-Down Delay
Deserializer Phase-Locked-
Loop Set from SSG Change
SYMBOL
RCOH
RCOL
RSRC
RHRC
RCCD
RPLLS
RPDD
RPLLS2
CONDITIONS
Figures 5a, 5b
Figures 5a, 5b
Figures 5a, 5b
Figures 5a, 5b
SSG = low, Figures 6a, 6b
Figure 7
Figure 8
Figure 9
Maximum output
frequency
Minimum output
frequency
Maximum output
frequency
Minimum output
frequency
f
RxCLKIN
+ 3.6%
f
RxCLKIN
- 4.4%
f
RxCLKIN
+ 1.8%
f
RxCLKIN
- 2.2%
f
RxCLKIN
f
RxCLKIN
/
1016
f
RxCLKIN
+ 4.0%
f
RxCLKIN
- 4.0%
f
RxCLKIN
+ 2.0%
f
RxCLKIN
- 2.0%
MIN
0.35 x
RCOP
0.35 x
RCOP
0.3 x
RCOP
0.45 x
RCOP
4.5 +
6.5 +
8.2 +
(RCIP / 2) (RCIP / 2) (RCIP / 2)
65,600 x
RCIP
100
32,800 x
RCIP
f
RxCLKIN
+ 4.4%
f
RxCLKIN
- 3.6%
f
RxCLKIN
+ 2.2%
f
RxCLKIN
- 1.8%
f
RxCLKIN
Hz
MHz
TYP
MAX
UNITS
ns
ns
ns
ns
ns
ns
ns
ns
MAX9242/MAX9244/MAX9246/MAX9254
SSG = high,
Figure 10
Spread-Spectrum Output
Frequency
f
RxCLKOUT
SSG = open,
Figure 10
SSG = low
Spread-Spectrum Modulation
Frequency
f
SSM
Figure 10
Note 1:
Current into a pin is defined as positive. Current out of a pin is defined as negative. All voltages are referenced to ground,
except V
TH
and V
TL
.
Note 2:
Maximum and minimum limits over temperature are guaranteed by design and characterization. Devices are production
tested at T
A
= +25°C.
Note 3:
To provide a mid level, leave the input open, or, if driven, put driver in high impedance. High-impedance leakage current
must be less than ±10µA.
Note 4:
RxCLKOUT limits are scaled based on RxOUT_ measurements, design, and characterization data.
Note 5:
One output shorted at a time. Current out of the pin.
Note 6:
V
TH
, V
TL
, and AC parameters are guaranteed by design and characterization, and are not production tested. Limits are set
at ±6 sigma.
Note 7:
C
L
includes probe and test jig capacitance.
Note 8:
RCIP is the period of RxCLKIN. RCOP is the period of RxCLKOUT.
Note 9:
RSKM is measured with less than 150ps cycle-to-cycle jitter on RxCLKIN.
_______________________________________________________________________________________
5
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