MAX9215 Maxim Integrated Products, MAX9215 Datasheet - Page 11

• Manufacturer Part Number: MAX9215
• Description: (MAX9209 - MAX9215) Programmable DC-Balanced 21-Bit Serializers
• Manufacturer: Maxim Integrated Products

Figure 9. PLL Set Time
Figure 10. Power-Down Delay
Figure 11. DC-Balanced Mode Inputs Mapped to LVDS Outputs
data channels is 10. At most, 10 more zeros than ones,
or 10 more ones than zeros, are transmitted. The maxi-
mum DSV for the clock channel is 5. Limiting the DSV
and choosing the correct coupling capacitors maintain
differential signal amplitude and reduce jitter due to
droop on AC-coupled links.
To obtain DC balance on the data channels, the parallel
input data is inverted or not inverted, depending on the
sign of the digital sum at the word boundary. Two com-
plementary bits are appended to each group of 7 paral-
lel input data bits to indicate to the MAX9210/MAX9212/
CYCLE N - 1
TxCLK OUT+
TxCLK OUT-
TxOUT2
TxOUT1
TxOUT0
DCA2
DCA1
DCA0
TxOUT_, TxCLK OUT
DCB2
DCB1
DCB0
PWRDWN
TxCLK IN
TxIN20
TxIN13
TxIN6
V
______________________________________________________________________________________
CC
TxIN19
TxIN12
TxIN5
HIGH-Z
TxOUT_, TxCLK OUT
TxIN18
TxIN11
TxIN4
PWRDWN
TxCLK IN
TxIN17
TxIN10
TxIN3
CYCLE N
TxIN16
TxIN9
TxIN2
2.0V
3.0V
TxIN15
TxIN8
TxIN1
Programmable DC-Balanced
TxIN14
TxIN7
TxIN0
V
TPPLS
OD
= 0
DCA2
DCA1
DCA0
MAX9214/MAX9216 deserializers whether the data bits
are inverted (Figure 11). The deserializer restores the
original state of the parallel data. The LVDS clock signal
alternates duty cycles of 4/9 and 5/9, which maintains
DC balance. Figure 12 shows the non-DC-balanced
mode inputs mapped to LVDS outputs.
Bit errors experienced with DC-coupling can be elimi-
nated by increasing the receiver common-mode volt-
age range by AC-coupling. AC-coupling increases the
DCB2
DCB1
DCB0
TxIN20
TxIN13
TxIN6
0.8V
TPDD
21-Bit Serializers
TxIN19
TxIN12
TxIN5
3.6V
TxIN18
TxIN11
HIGH-Z
TxIN4
AC-Coupling Benefits
CYCLE N + 1
TxIN17
TxIN10
TxIN3
TxIN16
TxIN9
TxIN2
DIFFERENTIAL 0
TxIN15
TxIN8
TxIN1
TxIN14
TxIN7
TxIN0
11