CADEKA CDK1301

Data Sheet
A m p l i fy t h e H u m a n E x p e r i e n c e
CDK1301
General Description
features
n
TTL/CMOS/PECL input logic compatible
n
High conversion rate: 250 MSPS
n
Single +5V power supply
n
Very low power dissipation: 425mW
n
350MHz full power bandwidth
n
Power-down mode: 24mW
n
+3.0V/+5.0V (LVCMOS) digital output The CDK1301 is a high-speed, 8-bit analog-to-digital converter implemented
in an advanced BiCMOS process. It is a performance-enhanced version of the
CDK1300, offering better linearity and dynamic performance. An advanced
folding and interpolating architecture provides both a high conversion
rate and very low power dissipation of only 425mW. The analog inputs can be
operated in either single-ended or differential input mode. A 2.5V common
mode reference is provided on chip for the single-ended input mode to minimize
external components.
logic compatibility
n
Single/demuxed output ports selectable
n
Improved replacement for AD9054
The CDK1301 digital outputs are demuxed (double-wide) with both dualchannel and single-channel selectable output modes. Demuxed mode supports
either parallel aligned or interleaved data output. The output logic is both +3.0V
and +5.0V compatible. The CDK1301 is available in a 44-lead TQFP surface
mount package over the industrial temperature range of -40°C to +85°C.
Applications
n
RGB video processing
n
Digital communications
n
High-speed instrumentation
n
Digital Sampling Oscilloscopes (DSO)
n
Projection display systems
Block Diagram
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
8-bit, 250 MSPS A/D Converter
with Demuxed Outputs
REV 1A
Ordering Information
Part Number
Package
Pb-Free
RoHS Compliant
Operating Temperature Range
Packaging Method
CDK1301ITQ44
TQFP-44
Yes
Yes
-40°C to +85°C
Rail
CDK1301ITQ44_Q
TQFP-44
No
No
-40°C to +85°C
Rail
Moisture sensitivity level for all parts is MSL-1.
©2008 CADEKA Microcircuits LLC www.cadeka.com
Data Sheet
Pin Configuration
TQFP-44
Pin Assignments
Pin No.
Pin Name
40
VIN+
Description
Non-inverted analog input; nominally 1Vpp; 100k pullup to Vcc and 100k pulldown to AGND, internally
39
VIN-
Inverted analog input; nominally 1Vpp; 100k pullup to Vcc and 100k pulldown to AGND, internally
16-9
DA0–DA7
Data output bank A; 3V/5V LVCMOS compatible
19-26
DB0–DB7
Data output bank B; 3V/5V LVCMOS compatible
28
DCLKOUT
Non-inverted data output clock; 3v/5v 3V/5V LVCMOS compatible
27
DCLKOUT
Inverted data output clock; 3V/5V LVCMOS compatible
4
CLK
Non-inverted clock input pin; 100k pulldown to AGND, internally
3
CLK
5
RESET
Inverted clock input pin; 17.5k pullup to Vcc and 7.5k pulldown to AGND, internally
RESET synchronizes the data sampling and data output bank relationship when in dual channel
mode (DMODE1 = 0); 100k pulldown to AGND, internally
6
RESET
REV 1A
Inverted RESET input pin; 17.5k pullup to Vcc and 7.5 pulldown to AGND, internally
Internally: 100k pulldown to AGND on DMODE1 50k pullup to Vcc on DMODE2
32, 31
DMODE1,2
Data output mode pins: DMODE1 = 0, DMODE2 = 0: parallel dual channel output
DMODE1 = 0, DMODE2 = 1: interleaved dual channel output
DMODE1 = 1, DMODE2 = x: single channel data output on bank a (125 MSPS max)
2
PD
Power-Down pin; PD = 1 for Power-Down mode. Outputs set to high impedance in Power-Down
mode; 100k pulldown to AGND, internally
37
VCM
2.5V common mode voltage reference output
35, 36,
42, 43
AVCC
+5V analog supply
7, 17, 30
OVDD
+3V/+5V digital output supply
1, 33, 34,
38, 41, 44
AGND
Analog ground
8, 18, 29
DGND
Digital ground
©2008 CADEKA Microcircuits LLC www.cadeka.com
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
CDK1301
2
Data Sheet
Absolute Maximum Ratings
The safety of the device is not guaranteed when it is operated above the “Absolute Maximum Ratings”. The device
should not be operated at these “absolute” limits. Adhere to the “Recommended Operating Conditions” for proper device function. The information contained in the Electrical Characteristics tables and Typical Performance plots reflect the
operating conditions noted on the tables and plots.
Supply Voltage
AVCC
OVDD
Input Voltages
Analog inputs
Digital inputs
Min
-0.5V
-0.5V
Max
Unit
+6
+6
V
V
Vcc +0.5V
Vcc +0.5V
V
V
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
Parameter
Reliability Information
Parameter
Min
Storage Temperature Range
-65
Typ
Max
Unit
+125
°C
Max
Unit
+85
°C
Recommended Operating Conditions
Parameter
Min
Operating Temperature Range
-40
Typ
REV 1A
©2008 CADEKA Microcircuits LLC www.cadeka.com
3
Data Sheet
Electrical Characteristics
(TA = TMin to TMax, AVCC= +5V, OVDD = +5V, ƒclk = 250MHz, 50% duty cycle,
ƒIN = 70MHz, dual channel mode; unless otherwise noted)
Symbol
Parameter
Conditions
Min
Resolution
Typ
Max
8
Units
bits
DLE
ILE
+25°C, ƒIN = 1KHz(1)
Differential Linearity Error
-0.68
-40°C to +85°C, ƒIN = 1KHz
Integral Linearity Error
No Missing Codes
0.68
LSB
±0.7
0.95
LSB
±1.2
±1.90
LSB
-40°C to +85°C, ƒIN = 1KHz(2)
±1.4
±2.15
LSB
@250 MSPS, ƒIN = 1KHz
-0.95
±0.4
+25°C, ƒIN = 1KHz(1)
(2)
Guaranteed
(1)
Analog Input
Input Voltage Range
VCM
PSRR
with respect to VIN-
±512
Input Common Mod
2.0
(2)
2.5
mVpp
3.0
V
Input Bias Current
+25°C
13
µA
Input Resistance
+25°C
50
kΩ
Input Capacitance
+25°C
Input Bandwidth
+25°C (-3dB of FS)
Gain Error(1)
+25°C
-7.5
Offset Error
+25°C
-5
(1)
Offset Power Supply Rejection Ratio
AVcc = 5V ±0.25V
5
pF
350
MHz
+3.5
%FS
+5
LSB
<1
LSB
250
MSPS
Timing Characteristics
25
Conversion Rate(2)
tpd1
tap
Output Delay (Clock-to-Data)
(2)
-40°C to +85°C
7
8
9.4
ns
Output Delay Tempco
16
ps/°C
Aperture Delay Time
0.3
ns
Aperture Jitter Time
2.0
ps-RMS
Single Channel Mode
2.5
Cycle
Demuxed Interleaved Mode
2.5
Cycle
Channel B
2.5
Cycle
Channel A
3.5
Cycle
Pipeline Delay (Latency)
Demuxed Parallel Mode
CLK to DCLKOUT Delay Time
Single Channel Mode(2)
5.0
tpd3
Dual Channel Mode
5.6
(2)
Output Delay (Clock to DClock)
5.18
5.3
5.73
5.9
ns
ns
18.1
ps/°C
Dynamic Performance
ENOB
SNR
THD
SINAD
Effective Number of Bits
Signal-to-Noise Ratio
Total Harmonic Distortion
Signal-to-Noise and Distortion
ƒIN = 70MHz, +25°C(1)
6.4
7.0
Bits
ƒIN = 70MHz, -40°C to +85°C(2)
6.25
6.8
Bits
ƒIN = 70MHz,+25°C(1)
44.3
46.1
dB
42.6
45.4
ƒIN = 70MHz, -40°C to +85°C
(2)
ƒIN = 70MHz, +25°C(1)
ƒIN = 70MHz, -40°C to +85°C(2)
ƒIN = 70MHz, +25°C
(1)
ƒIN = 70MHz, -40°C to +85°C(2)
dB
-47
-41.5
dB
-45.5
-40.3
dB
40.2
43.7
dB
39.3
42.8
dB
Notes:
1. 100% production tested at +25°C.
2. Parameter is guaranteed (but not tested) by design and characterization data.
©2008 CADEKA Microcircuits LLC www.cadeka.com
4
REV 1A
tpd2
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
DC Performance
Data Sheet
Electrical Characteristics
(TA = TMin to TMax, AVCC= +5V, OVDD = +5V, ƒclk = 250MHz, 50% duty cycle,
ƒIN = 70MHz, dual channel mode; unless otherwise noted)
Symbol
Parameter
Conditions
Min
Typ
Max
Units
5.0
5.25
V
5.25
V
85
110
mA
4.8
5.5
mA
Power Supply Requirements
Analog Voltage Supply(2)
4.75
OVDD
Digital Voltage Supply(2)
2.75
AIcc
OIDD
Current
(1)
Current Power-down(1)
+25°C
Current
OVDD = 3.0V, 10pF load
Single Mode
35
mA
Parallel Mode
55
mA
Interleave Mode
55
mA
Power Dissipation
(1)
425
550
mW
2.5
2.56
V
Common Mode Reference Output
Voltage(1)
2.44
Voltage Tempcp
84
Open Impedance
PSRR
IOUT = ±50µA
Power Supply Rejection Ratio
ppm/°C
1.07
kΩ
47.5
mV/V
Clock and Reset Inputs (Differential and Single-Ended)
VDIFF
Differental Signal Amplitude(2)
400
VIHD
Differental High Input Voltage(2)
1.4
AVcc
V
VILD
Differental Low Input Voltage(2)
0
3.9
V
VCMD
Differental Common Mode Input
(2)
1.2
4.1
V
VIH
Single-Ended High Input Voltage(1)
1.8
VIL
Single-Ended Low Input Voltage(2)
0
IIH
High Input Current
IIL
Low Input Current(1)
(1)
mVpp
V
1.2
V
VID = 1.5V
-100
43
+100
µA
VID = 1.5V
-100
43
+100
µA
V
Power Down and Mode Control Inputs (Single-Ended)
High Input Voltage(2)
2.0
AVcc
Low Input Voltage(2)
0
1.0
V
Max Input Current Low(1)
-100
0.5
+100
µA
Max Input Current High <4.0V(1)
-100
50
+100
µA
Digital Outputs
IOH = -0.5mA
Logic “0“ Voltage
IOL = +1.6mA
TR/TF Data
TR/TF DCLK
(1)
OVDD-2.0
V
0.2
V
OVDD = 3V, 10pF load
3.3/3.0
ns
OVDD = 5V, 10pF load
2.3/1.9
ns
OVDD = 3V, 10pF load
1.2/1.0
ns
OVDD = 5V, 10pF load
0.7/0.6
ns
REV 1A
Logic “1“ Voltage(1)
Notes:
1. 100% production tested at +25°C.
2. Parameter is guaranteed (but not tested) by design and characterization data.
©2008 CADEKA Microcircuits LLC www.cadeka.com
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
AVcc
5
Data Sheet
Typical Performance Characteristics
(TA = TMin to TMax, AVCC= +5V, OVDD = +5V, ƒclk = 250MHz, 50% duty cycle,
ƒIN = 70MHz, dual channel mode; unless otherwise noted)
DLE vs. Sample Rate
DLE vs. Temperature
ƒIN = 70.1 MHz
LSB
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
-0.1
-0.2
-0.3
-0.4
-0.5
-0.6
-0.7
200
225
250
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
-0.1
-0.2
-0.3
-0.4
-0.5
-0.6
-0.7
260
ƒIN = 70.1MHz
ƒS = 250 MSPS
-50
-25
DLE vs. AVcc
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
-0.1
-0.2
-0.3
-0.4
-0.5
-0.6
-0.7
100
90
80
ƒIN = 70.1MHz
ƒS = 250 MSPS
70
60
50
40
30
10
0
4.5 4.6 4.7 4.8 4.9 5.0 5.1 5.2 5.3 5.4 5.5
Powerdown mode
-50
-25
0
25
50
75
100
Temperature (°C)
SNR, SINAD vs. Sample Rate
SFDR, THD vs. Sample Rate
60
-35
50
SFDR, THD (dB)
ƒIN = 70.1 MHz
SNR
45
SINAD
40
35
30
REV 1A
-30
55
SNR, SINAD (dB)
75
20
ƒIN = 70.1 MHz
-40
THD
-45
-50
SFDR
-55
-60
-65
25
20
50
100
ƒIN = 70.1MHz
ƒS = 250 MSPS
Volts (V)
25
AVcc Current vs. Temperature
AVCC Current (mA)
LSB
0
Temperature (°C)
Sample Rate (MSPS)
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
LSB
200
225
Sample Rate (MSPS)
©2008 CADEKA Microcircuits LLC 250
260
-70
200
225
250
260
Sample Rate (MSPS)
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6
Data Sheet
Typical Performance Characteristics
(TA = TMin to TMax, AVCC= +5V, OVDD = +5V, ƒclk = 250MHz, 50% duty cycle,
ƒIN = 70MHz, dual channel mode; unless otherwise noted)
SNR, SINAD vs. Temperature
THD vs. Temperature
60
-30
-40
SNR
45
SINAD
40
35
-45
-50
-55
30
-60
25
-65
20
-50
-25
0
25
50
ƒIN = 70.1 MHz
ƒS = 250 MSPS
-35
THD (dB)
SNR, SINAD (dB)
50
75
-70
100
-50
-25
Temperature (°C)
50
SFDR, THD (dB)
SNR, SINAD (dB)
75
100
SNR
45
SINAD
40
ƒIN = 70.1 MHz
ƒS = 250 MSPS
-35
35
30
-40
-45
THD
-50
SFDR
-55
-60
-65
25
35
40
45
50
55
-70
60
35
40
45
50
55
60
Duty Cycle (%)
Duty Cycle (%)
SNR, SINAD vs. AVcc
THD vs. AVCC
60
50
-40
40
35
THD (dB)
SINAD
-45
-50
-55
30
-60
25
-65
4.5 4.6 4.7 4.8 4.9 5.0 5.1 5.2 5.3 5.4 5.5
Volts (V)
©2008 CADEKA Microcircuits LLC ƒIN = 70.1 MHz
ƒS = 250 MSPS
-35
SNR
45
REV 1A
-30
ƒIN = 70.1 MHz
ƒS = 250 MSPS
55
SNR, SINAD (dB)
50
-30
ƒIN = 70.1 MHz
ƒS = 250 MSPS
55
20
25
SFDR, THD vs. Duty Cycle
60
0
Temperature (°C)
SNR, SINAD vs. Duty Cycle
20
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
ƒIN = 70.1 MHz
ƒS = 250 MSPS
55
-70
4.5 4.6 4.7 4.8 4.9 5.0 5.1 5.2 5.3 5.4 5.5
Volts (V)
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7
Data Sheet
Theory of Operation
The analog decode functions are the input buffer, input
THAs, three-bit folder, folding interpolators, and pipelining
THAs. The input buffer enables the part to withstand railto-rail input signals without latchup or excessive currents
and also performs single-ended to differential conversion.
All of the THAs have the same basic architecture. Each
has a differential pair buffer followed by switched emitter
followers driving the hold capacitors. The input THA also
has hold mode feedthrough cancellation devices.
The three MSBs of the ADC are generated in the first
threebit folder block, the output of which drives a differential reference ladder which also sets the full-scale
input range. Differential pairs at the ladder taps generate midscale, quarter and three-quarter scale, overrange,
and underrange. Every other differential pair collector is
cross-coupled to generate the eighth scale zero crossings.
The middle ADC block generates two bits from the folded
signals of the previous stages after pipeline THAs. Its outputs drive more pipeline THAs to push the decoding of the
three LSBs to the next half clock cycle. The three LSBs are
generated in interpolators that are latched one full clock
cycle after the MSBs.
The digital decode consists of comparators, exclusive of
The output data mode is controlled by the state of the
demux mode inputs. There are three output modes:
All data on bank A with clock rate limited to one-half maximum
n
Interleaved mode with data alternately on banks A and B on alternate clock cycles
n
Parallel mode with bank A delayed one cycle to be synchronous with bank B every other clock cycle
n
If necessary, the input clock is divided by two. The
divided clock selects the correct output bank. The user
can synchronize with the divided clock to select the
desired output bank via the differential RESET input.
The output logic family is CMOS with output OVDD supply
adjustable from 2.7V to 5.25V. There are also differential
clock output pins that can be used to latch the output data
in single bank mode or to indicate the current output bank
in demux mode.
Finally, a power-down mode is available, which causes the
outputs to become tri-state, and overall power is reduced
to about 24mW. There is a 2V reference to supply common mode for single-ended inputs that is not shut down
in powerdown mode.
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
The CDK1301 is a three-step subranger. It consists of
two THAs in series at the input, followed by three ADC
blocks. The first block is a three-bit folder with over/under
range detection. The second block consists of two singlebit folding interpolator stages. There are pipelining THAs
between each ADC block.
cells for gray to binary decoding, and/or cells used for
mostly over/under range logic. There is a total of 2.5
clock cycles latency before the output bank selection. In
order to reduce sparkle codes and maintain sample rate,
no more than three bits at a time are decoded in any half
clock cycle.
REV 1A
Figure 1. Single Mode Timing Diagram
©2008 CADEKA Microcircuits LLC www.cadeka.com
8
Data Sheet
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
REV 1A
Figure 2. Dual Mode Timing Diagram
©2008 CADEKA Microcircuits LLC www.cadeka.com
9
Data Sheet
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
CDK1301
Figure 3. Typical Interface Circuit
REV 1A
Figure 4. CLK and Reset Equivalent Circuit
(without ESD Diodes)
Figure 5. Analog Input Equivalent Circuit
Typical Interface Circuit
Analog Input
Very few external components are required to achieve
the stated device performance. Figure 3 shows the typical
interface requirements when using the CDK1301 in normal circuit operation. The following sections provide
descriptions of the major functions and outline performance
criteria to consider for achieving the optimal device
performance.
The input of the CDK1301 can be configured in various
ways depending on whether a single-ended or differential
input is desired.
©2008 CADEKA Microcircuits LLC The AC-coupled input is most conveniently implemented
using a transformer with a center-tapped secondary winding.
The center tap is connected to the VCM pin as shown in
Figure 3. To obtain low distortion, it is important that the
www.cadeka.com
10
Data Sheet
selected transformer does not exhibit core saturation at
the full-scale voltage. Proper termination of the input is
important for input signal purity. A small capacitor across
the input attenuates kickback noise from the internal trackand-hold.
The CDK1301 has an on-board common-mode voltage
reference circuit (VCM). It is 2.5V and is capable of driving
50μA loads typically. The circuit is commonly used to drive
the center tap of the RF transformer in fully differential
applications. For single-ended applications, this output
can be used to provide the level shifting required for the
single-to-differential converter conversion circuit. Bypass
VCM to AGND by external 0.01μF capacitor, as shown in
Figure 3 on the previous page.
Clock Input
The clock input on the CDK1301 can be driven by
either a single-ended or double-ended clock circuit and
can handle TTL, PECL, and CMOS signals. When operating
at high sample rates it is important to keep the pulse width
of the clock signal as close to 50% as possible. For TTL/
CMOS single- ended clock inputs, the rise time of the signal
also becomes an important consideration.
Figure 6. DC-Coupled Single-Ended to Differential
Conversion (power supplies and bypassing are not shown)
Input Protection
All I/O pads are protected with an on-chip protection circuit. This circuit provides ESD robustness and prevents
latchup under severe discharge conditions without degrading analog transmission times.
Power Supplies and Grounding
Power-Down Mode
To save on power, the CDK1301 incorporates a powerdown function. This function is controlled by the signal on
pin PD. When pin PD is set high, the CDK1301 enters the
power-down mode. All outputs are set to high impedance.
In the powerdown mode the CDK1301 dissipates 24mW
typically.
©2008 CADEKA Microcircuits LLC The output circuitry of the CDK1301 has been designed
to be able to support three separate output modes. The
demuxed (double-wide) mode supports either parallel
aligned or interleaved data output. The single-channel mode
is not demuxed and can support direct output at speeds up
to 125 MSPS. The output format is straight binary (Table 1).
Table 1. Output Data Format
Analog Input
Output Code D7–D0
+FS
1111 1111
+FS - 1 LSB
1111 111Ø
+1 FS
1000 000Ø
-FS + 1 LSB
0000 000Ø
-FS
0000 0000
REV 1A
The CDK1301 is operated from a single power supply in
the range of 4.75V to 5.25V. Normal operation is suggested to be 5.0V. All power supply pins should be bypassed
as close to the package as possible. The analog and digital
grounds should be connected together with a ferrite bead
as shown in the typical interface circuit and as close to the
ADC as possible.
Digital Outputs
Ø indicates the flickering bit between logic 0 and 1
The data output mode is set using the DMODE1 and
DMODE2 inputs (pins 32 & 31 respectively). Table 2 describes
the mode switching options.
Table 2. Output Data Modes
Output Mode
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
Figure 6 illustrates a solution (based on operational amplifiers) that can be used if a DC-coupled single-ended input
is desired.
Common-Mode Voltage Reference Circuit
DMODE1
DMODE2
Parallel Dual Channel Output
0
0
Interleaved Dual Channel Output
0
1
Single Channel Data Output
(Bank A only 125 MSPS max)
1
X
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11
Data Sheet
Evaluation Board
(1:1). An application note (TBD) describing the operation
of this board, as well as information on the testing of
the CDK1301, is also available. Contact the factory for
price and availability of the TBD.
Mechanical Dimensions
TQFP-44 Package
TQFP-44
A
B
INCHES
PIN1
Index
C D
E
SYMBOL
A
B
C
D
E
F
G
H
I
J
K
MIN
TYP
0.472
0.394
0.394
0.472
0.031
0.012
0.053
0.002
0.018
0.039
0-7°
MILLIMETERS
MAX
MIN
0.018
0.057
0.006
0.030
0.300
1.35
0.05
0.45
TYP MAX
12.00
10.00
10.00
12.00
0.80
0.45
1.45
0.15
0.75
1.00
0-7°
F
G
H
I
K
J
CDK1301 8-bit, 250 MSPS A/D Converter with Demuxed Outputs
The TBD evaluation board is available to aid designers in
demonstrating the full performance of the CDK1301. This
board includes a clock driver and reset circuit, adjustable
references and common mode, a single-ended to differential
input buffer and a single-ended to differential transformer
REV 1A
For additional information regarding our products, please visit CADEKA at: cadeka.com
CADEKA Headquarters Loveland, Colorado
T: 970.663.5452
T: 877.663.5452 (toll free)
CADEKA, the CADEKA logo design, COMLINEAR and the COMLINEAR logo design are trademarks or registered trademarks of CADEKA
Microcircuits LLC. All other brand and product names may be trademarks of their respective companies.
CADEKA reserves the right to make changes to any products and services herein at any time without notice. CADEKA does not assume any
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