LTC2271
6
2271f
TIMING CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating temperature
range, otherwise specifi cations are at T
A
= 25°C. (Note 5)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
f
S
Sampling Frequency (Note 10)
l
5 20 MHz
t
ENCL
ENC Low Time (Note 8) Duty Cycle Stabilizer Off
Duty Cycle Stabilizer On
l
l
23.5
2
25
25
100
100
ns
ns
t
ENCH
ENC High Time (Note 8) Duty Cycle Stabilizer Off
Duty Cycle Stabilizer On
l
l
23.5
2
25
25
100
100
ns
ns
t
AP
Sample-and-Hold
Acquistion Delay Time
0ns
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: All voltage values are with respect to GND with GND and OGND
shorted (unless otherwise noted).
Note 3: When these pin voltages are taken below GND or above V
DD
, they
will be clamped by internal diodes. This product can handle input currents
of greater than 100mA below GND or above V
DD
without latchup.
Note 4: When these pin voltages are taken below GND they will be
clamped by internal diodes. When these pin voltages are taken above V
DD
they will not be clamped by internal diodes. This product can handle input
currents of greater than 100mA below GND without latchup.
Note 5: V
DD
= OV
DD
= 1.8V, f
SAMPLE
= 20MHz, 2-lane output mode,
differential ENC
+
/ENC
–
= 2V
P-P
sine wave, input range = 2.1V
P-P
with
differential drive, unless otherwise noted.
Note 6: Integral nonlinearity is defi ned as the deviation of a code from a
best fi t straight line to the transfer curve. The deviation is measured from
the center of the quantization band.
Note 7: Offset error is the offset voltage measured from –0.5LSB when the
output code fl ickers between 0000 0000 0000 0000 and 1111 1111 1111
1111 in 2’s complement output mode.
Note 8: Guaranteed by design, not subject to test.
Note 9: V
DD
= OV
DD
=1.8V, f
SAMPLE
= 20MHz, 2-lane output mode, ENC
+
= single-ended 1.8V square wave, ENC
–
= 0V, input range = 2.1V
P-P
with
differential drive, unless otherwise noted. The supply current and power
dissipation specifi cations are totals for the entire IC, not per channel.
Note 10: Recommended operating conditions.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Digital Data Outputs (R
TERM
= 100Ω Differential, C
L
= 2pF to GND On Each Output)
t
SER
Serial Data Bit Period 4-Lane Output Mode
2-Lane Output Mode
1-Lane Output Mode
1/(4 • f
S
)
1/(8 • f
S
)
1/(16 • f
S
)
Sec
t
FRAME
FR to DCO Delay (Note 8)
l
0.35 • t
SER
0.5 • t
SER
0.65 • t
SER
Sec
t
DATA
Data to DCO Delay (Note 8)
l
0.35 • t
SER
0.5 • t
SER
0.65 • t
SER
Sec
t
PD
Propagation Delay (Note 8)
l
0.7n + 2 • t
SER
1.1n + 2 • t
SER
1.5n + 2 • t
SER
Sec
t
r
Output Rise Time Data, DCO, FR, 20% to 80% 0.17 ns
t
f
Output Fall Time Data, DCO, FR, 20% to 80% 0.17 ns
DCO Cycle-Cycle Jitter t
SER
= 3.1ns 60 ps
P-P
Pipeline Latency 7 7 Cycles
SPI Port Timing (Note 8)
t
SCK
SCK Period Write Mode
Readback Mode,
C
SDO
= 20pF, R
PULLUP
= 2k
l
l
40
250
ns
ns
t
S
CS-to-SCK Setup Time
l
5ns
t
H
SCK-to-CS Setup Time
l
5ns
t
DS
SDI Setup Time
l
5ns
t
DH
SDI Hold Time
l
5ns
t
DO
SCK Falling to SDO
Valid
Readback Mode,
C
SDO
= 20pF, R
PULLUP
= 2k
l
125 ns
