TI ADS6149IRGZT

ADS6149/ADS6129
ADS6148/ADS6128
www.ti.com ..................................................................................................................................................... SLWS211B – JULY 2008 – REVISED OCTOBER 2008
14/12-Bit, 250/210 MSPS ADCs With DDR LVDS and Parallel CMOS Outputs
FEATURES
1
•
•
•
•
•
•
•
•
•
•
•
Maximum Sample Rate: 250 MSPS
14-Bit Resolution – ADS614X
12-Bit Resolution – ADS612X
687 mW Total Power Dissipation at 250 MSPS
Double Data Rate (DDR) LVDS and Parallel
CMOS Output Options
Programmable Fine Gain up to 6dB for
SNR/SFDR Trade-Off
DC Offset Correction
Supports Input Clock Amplitude Down to 400
mVPP Differential
Internal and External Reference Support
48-QFN Package (7mm × 7mm)
Pin Compatible with ADS5547 Family
APPLICATIONS
•
•
•
•
•
•
•
•
•
Multicarrier, Wide Band-Width
Communications
Wireless Multi-carrier Communications
Infrastructure
Software Defined Radio
Power Amplifier Linearization
802.16d/e
Test and Measurement Instrumentation
High Definition Video
Medical Imaging
Radar Systems
DESCRIPTION
ADS614X (ADS612X) is a family of 14-bit (12-bit) A/D
converters with sampling rates up to 250 MSPS. It
combines high dynamic performance and low power
consumption in a compact 48 QFN package. This
makes it well-suited for multicarrier, wide band-width
communications applications.
ADS614X/2X has fine gain options that can be used
to improve SFDR performance at lower full-scale
input ranges. It includes a dc offset correction loop
that can be used to cancel the ADC offset. Both DDR
LVDS (Double Data Rate) and parallel CMOS digital
output interfaces are available. At lower sampling
rates, the ADC automatically operates at scaled down
power with no loss in performance.
It includes internal references while the traditional
reference pins and associated decoupling capacitors
have been eliminated. Nevertheless, the device can
also be driven with an external reference. The device
is specified over the industrial temperature range
(–40°C to 85°C).
250 MSPS
210 MSPS
ADS614X
14-Bit Family
ADS6149
ADS6148
ADS612X
12-Bit Family
ADS6129
ADS6128
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2008, Texas Instruments Incorporated
ADS6149/ADS6129
ADS6148/ADS6128
SLWS211B – JULY 2008 – REVISED OCTOBER 2008 ..................................................................................................................................................... www.ti.com
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
DRGND
DRVDD
AGND
AVDD
ADS614X BLOCK DIAGRAM
DDR LVDS Interface
CLKP
CLKOUTP
CLOCKGEN
CLKM
CLKOUTM
D0_D1_P
D0_D1_M
D2_D3_P
D2_D3_M
D4_D5_P
D4_D5_M
INP
INM
Sample
and
Hold
DDR
Serializer
14-Bit ADC
D6_D7_P
D6_D7_M
D8_D9_P
D8_D9_M
D10_D11_P
D10_D11_M
VCM
Control
Interface
Reference
D12_D13_P
D12_D13_M
OVR_SDOUT
DFS
MODE
SDATA
SEN
SCLK
RESET
ADS6149/48
B0095-06
2
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DRGND
DRVDD
AGND
AVDD
ADS612X BLOCK DIAGRAM
DDR LVDS Interface
CLKP
CLKOUTP
CLOCKGEN
CLKM
CLKOUTM
D0_D1_P
D0_D1_M
D2_D3_P
D2_D3_M
D4_D5_P
D4_D5_M
INP
INM
Sample
and
Hold
DDR
Serializer
12-Bit ADC
D6_D7_P
D6_D7_M
D8_D9_P
D8_D9_M
D10_D11_P
D10_D11_M
VCM
Control
Interface
Reference
OVR_SDOUT
DFS
MODE
SDATA
SEN
SCLK
RESET
ADS6129/28
B0095-07
Copyright © 2008, Texas Instruments Incorporated
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PACKAGE/ORDERING INFORMATION (1) (2)
PRODUCT
PACKAGE-LEAD
PACKAGE
DESIGNATOR
SPECIFIED
TEMPERATURE
RANGE
LEAD/BALL
FINISH
PACKAGE
MARKING
ORDERING
NUMBER
TRANSPORT
MEDIA, QUANTITY
ADS614x
ADS6149
AZ6149
QFN-48
RGZ
–40°C to 85°C
Cu NiPdAu
ADS6148
AZ6148
ADS6149IRGZR
ADS6149IRGZT
ADS6148IRGZR
Tape and reel
ADS6148IRGZT
ADS612x
ADS6129
AZ6129
QFN-48
RGZ
–40°C to 85°C
ADS6128
(1)
(2)
Cu NiPdAu
AZ6128
ADS6129IRGZR
ADS6129IRGZT
ADS6128IRGZR
Tape and reel
ADS6128IRGZT
For thermal pad size on the package, see the mechanical drawings at the end of this data sheet. θJA = 25.41° C/W (0LFM air flow),
θJC = 16.5°C/W when used with 2oz. copper trace and pad soldered directly to a JEDEC standard four layer 3 in x 3 in (7.62 cm x 7.62
cm) PCB.
For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI
website at www.ti.com.
ABSOLUTE MAXIMUM RATINGS (1)
VALUE
UNIT
Supply voltage range, AVDD
–0.3 V to 3.9
V
Supply voltage range, DRVDD
–0.3 V to 2.2
V
–0.3 to 0.3
V
Voltage between AVDD to DRVDD (when AVDD leads DRVDD)
0 to 3.3
V
Voltage between DRVDD to AVDD (when DRVDD leads AVDD)
–1.5 to 1.8
V
Voltage applied to external pin, VCM (in external reference mode)
–0.3 to 2.0
V
–0.3V to minimum
( 3.6, AVDD + 0.3V )
V
–0.3V to AVDD + 0.3V
V
Voltage between AGND and DRGND
VI
Voltage applied to analog input pins - INP, INM
Voltage applied to input pins - CLKP, CLKM (2), RESET, SCLK, SDATA, SEN, DFS and
MODE
TA
Operating free-air temperature range
–40 to 85
°C
TJ
Operating junction temperature range
125
°C
Tstg
Storage temperature range
–65 to 150
°C
(1)
(2)
4
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 under recommended operating
conditions is not implied. Exposure to absolute maximum rated conditions for extended periods may affect device reliability.
When AVDD is turned off, it is recommended to switch off the input clock (or ensure the voltage on CLKP, CLKM is < |0.3V|. This
prevents the ESD protection diodes at the clock input pins from turning on.
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RECOMMENDED OPERATING CONDITIONS
over operating free-air temperature range (unless otherwise noted)
MIN
TYP
MAX
UNIT
3
3.3
3.6
V
1.7
1.8
1.9
V
SUPPLIES
AVDD
Analog supply voltage
DRVDD
Digital supply voltage
ANALOG INPUTS
Differential input voltage range
2
Input common-mode voltage
Vpp
1.5 ±0.1
Voltage applied on CM in external reference mode
V
1.5 ± 0.05
V
Maximum analog input frequency with 2 VPP input amplitude (1)
500
MHz
Maximum analog input frequency with 1 VPP input amplitude (1)
800
MHz
CLOCK INPUT
Input clock sample rate
ADS6149 / ADS6129
1
250
ADS6148 / ADS6128
1
210
Sine wave, ac-coupled
Input Clock amplitude differential
(VCLKP–VCLKM)
0.3
1.5
LVPECL, ac-coupled
1.6
LVDS, ac-coupled
0.7
LVCMOS, single-ended, ac-coupled
Vpp
3.3
Input clock duty cycle
40%
MSPS
50%
V
60%
DIGITAL OUTPUTS
CL
Maximum external load capacitance from each output pin to DRGND
RL
Differential load resistance between the LVDS output pairs (LVDS mode)
TA
Operating free-air temperature
(1)
5
pF
Ω
100
–40
85
°C
See the Theory of Operation in the application section.
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ELECTRICAL CHARACTERISTICS – ADS614X and ADS612X
Typical values are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, 50% clock duty cycle, –1dBFS differential analog input, internal
reference mode unless otherwise noted.
Min and max values are across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = 3.3 V, DRVDD = 1.8 V
PARAMETER
ADS6149/ADS6129
250 MSPS
MIN
TYP MAX
ADS6148/ADS6128
210 MSPS
MIN
TYP
UNIT
MAX
ANALOG INPUT
Differential input voltage range
Differential input resistance (at dc), See Figure 97
2
2
VPP
>1
>1
MΩ
Differential input capacitance, See Figure 98
3.5
3.5
pF
Analog Input Bandwidth
700
700
MHz
2
2
VCM Common mode output voltage
1.5
1.5
V
VCM output current capability
±4
±4
mA
Analog Input common mode current (per input pin)
µA/MSPS
DC ACCURACY
Offset error
–15
Temperature coefficient of offset error
Variation of offset error with supply
EGREF
Gain error due to internal reference inaccuracy alone
EGCHAN
Gain error of channel alone
Temperature coefficient of EGCHAN
–1.25
±2
15
–15
±2
0.005
0.005
0.3
0.3
±0.2
1.25
–1.25
±0.2
15
mV
mV/°C
mV/V
1.25
%FS
0.2
0.2
%FS
.001
.001
Δ%/°C
POWER SUPPLY
IAVDD
IDRVDD
Analog supply current
170
155
mA
Output buffer supply current, LVDS interface with 100 Ω external
termination
70
65
mA
Output buffer supply current, CMOS interface Fin = 3 MHz (1),
10-pF external load capacitance
56
48
mA
Analog power
561
630
510
570
mW
Digital power LVDS interface
126
160
118
153
mW
Digital power CMOS interface, Fin = 3 MHz (2), 10-pF external
load capacitance
101
Global power down
20
Standby
(1)
(2)
6
87
50
120
20
120
mW
50
mW
mW
In CMOS mode, the DRVDD current scales with the sampling frequency, the load capacitance on output pins, input frequency and the
supply voltage (see Figure 91 and CMOS interface power dissipation in application section).
The maximum DRVDD current with CMOS interface depends on the actual load capacitance on the digital output lines. Note that the
maximum recommended load capacitance on each digital output line is 10 pF.
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www.ti.com ..................................................................................................................................................... SLWS211B – JULY 2008 – REVISED OCTOBER 2008
ELECTRICAL CHARACTERISTICS – ADS6149 and ADS6148
Typical values are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, 50% clock duty cycle, –1dBFS differential analog input, internal
reference mode unless otherwise noted.
Min and max values are across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = 3.3 V, DRVDD = 1.8 V
ADS6149
250 MSPS
PARAMETER
MIN
SNR
Signal to noise ratio, LVDS
MIN
73.4
73.4
72.7
72.7
Fin = 100 MHz
72.3
72.3
69
71.3
69.7
69
Fin = 20 MHz
73.2
73.3
Fin = 80 MHz
72.4
72.4
Fin = 100 MHz
71.9
68
Fin = 300 MHz
71.8
70.6
68.7
68
Fin = 170 MHz
11
11.4
DNL
Differential non-linearity
–0.95
±0.4
INL
Integrated non-linearity
–5
±2
dBFS
71.2
69
Fin = 170 MHz
UNIT
TYP MAX
Fin = 80 MHz
Fin = 300 MHz
ENOB
Effective number of bits
TYP MAX
Fin = 20 MHz
Fin = 170 MHz
SINAD
Signal to noise and distortion ratio, LVDS
ADS6148
210 MSPS
dBFS
70.9
68.2
11.1
11.5
LSB
2
–0.95
±0.4
2
LSB
5
–5
±2
5
LSB
ELECTRICAL CHARACTERISTICS – ADS6129 and ADS6128
Typical values are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, 50% clock duty cycle, –1dBFS differential analog input, internal
reference mode unless otherwise noted.
Min and max values are across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = 3.3 V, DRVDD = 1.8 V
PARAMETER
ADS6129
250 MSPS
MIN
SNR,
Signal to noise ratio, LVDS
TYP
70.7
70.9
70.5
70.5
Fin = 100 MHz
70.1
70.1
67.5
69.5
67.7
67.8
67.9
Fin = 20 MHz
70.6
70.8
Fin = 80 MHz
70.4
70.4
Fin = 100 MHz
69.8
66.5
Fin = 170 MHz
66.7
67.2
11.2
DNL
Differential non-linearity
–0.5
±0.2
INL
Integrated non-linearity
–2.5
±1
dBFS
69.8
69.2
10.8
UNIT
MAX
69.5
Fin = 300 MHz
Fin = 300 MHz
Copyright © 2008, Texas Instruments Incorporated
MIN
Fin = 80 MHz
Fin = 170 MHz
ENOB,
Effective number of bits
TYP MAX
Fin = 20 MHz
Fin = 170 MHz
SINAD
Signal to noise and distortion ratio, LVDS
ADS6128
210 MSPS
dBFS
69.3
67.3
10.8
11.2
LSB
1
–0.5
±0.2
1.0
LSB
2.5
–2.5
±1
2.5
LSB
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ELECTRICAL CHARACTERISTICS – ADS614x and ADS612x
Typical values are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, 50% clock duty cycle, –1dBFS differential analog input, internal
reference mode unless otherwise noted.
Min and max values are across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = 3.3 V, DRVDD = 1.8 V
PARAMETER
ADS6149/ADS6129
250 MSPS
MIN
SFDR
Spurious Free Dynamic Range
92
92
86
82
Fin = 100 MHz
85
81
IMD
2-Tone inter-modulation distortion
74
76
89
88.5
Fin = 20 MHz
83
80
Fin = 80 MHz
82
71
79
79
71
73
73
Fin = 20 MHz
94
94
Fin = 80 MHz
90
88
Fin = 100 MHz
88
88
84
74
76
76
Fin = 20 MHz
93
92
Fin = 80 MHz
86
82
Fin = 100 MHz
85
82
81
74
dBc
dBc
84
Fin = 300 MHz
74
dBc
80
Fin = 300 MHz
74
UNIT
MAX
83
Fin = 10 MHz
dBc
83
Fin = 300 MHz
76
76
Fin = 20 MHz
96
96
Fin = 80 MHz
94
94
Fin = 100 MHz
94
94
Fin = 170 MHz
92
92
Fin = 300 MHz
90
90
F1 = 46 MHz, F2 = 50 MHz,
Each tone at –7 dBFS
94
95
F1 = 185 MHz, F2 = 190 MHz,
Each tone at –7 dBFS
90
90
1
1
clock
cycles
25
25
dB
Input overload recovery
Recovery to within 1% (of final value) for
6-dB overload with sine wave input
PSRR
AC power supply rejection ratio
For 100 mVPP signal on AVDD supply
8
82
76
Fin = 170 MHz
Worst Spur
Other than second, third harmonics
74
Fin = 300 MHz
Fin = 170 MHz
HD3
Third Harmonic Distortion
TYP
Fin = 80 MHz
Fin = 170 MHz
HD2,
Second Harmonic Distortion
MIN
Fin = 20 MHz
Fin = 170 MHz
THD
Total Harmonic Distortion
TYP MAX
ADS6148/ADS6128
210 MSPS
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dBc
dBFS
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DIGITAL CHARACTERISTICS – ADS614x and ADS612x
The DC specifications refer to the condition where the digital outputs are not switching, but are permanently at a valid logic
level 0 or 1. AVDD = 3.3 V, DRVDD = 1.8 V
PARAMETER
ADS6149/ADS6148/
ADS6129/ADS6128
TEST CONDITIONS
MIN
TYP
UNIT
MAX
DIGITAL INPUTS – RESET, SCLK, SDATA, SEN (1)
High-level input voltage
All digital inputs support 1.8V and 3.3V CMOS logic
levels
Low-level input voltage
High-level input current
Low-level input current
1.3
V
0.4
SDATA, SCLK (2)
VHIGH = 3.3V
16
SEN (3)
VHIGH = 3.3V
10
SDATA, SCLK
VLOW = 0V
0
SEN
VLOW = 0V
–20
Input capacitance
V
µA
µA
4
pF
High-level output voltage
DRVDD
V
Low-level output voltage
0
V
Output capacitance (internal to device)
2
pF
DIGITAL OUTPUTS – CMOS INTERFACE (Pins D0 to D13 and OVR_SDOUT)
DIGITAL OUTPUTS – LVDS INTERFACE (Pins D0_D1_P/M to D12_D13_P/M) (4)
VODH, High-level output voltage (5)
VODL, Low-level output voltage
(5)
275
350
425
mV
–425
–350
–275
mV
1
1.2
1.3
VOCM, Output common-mode voltage
Capacitance inside the device, from either output to
ground
Output capacitance
(1)
(2)
(3)
(4)
(5)
2
V
pF
SCLK, SDATA, SEN function as digital input pins in serial configuration mode.
SDATA, SCLK have internal 200 kΩ pull-down resistor
SEN has internal 100 kΩ pull-up resistor to AVDD. Since the pull-up is weak, SEN can also be driven by 1.8V or 3.3V CMOS buffers.
OVR_SDOUT has CMOS output logic levels, determined by DRVDD voltage.
With external 100 Ω termination
Dn_Dn+1_P
Dn_Dn+1_P
Logic 1
Logic 0
VODL = –350 mV
(1)
VODH = 350 mV
(1)
Dn_Dn+1_M
Dn_Dn+1_M
V
V
OCM
OCM
GND
GND
T0399-01
Figure 1. LVDS Voltage Levels
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TIMING REQUIREMENTS – LVDS AND CMOS MODES (1)
Typical values are at 25°C, AVDD = 3.3V, DRVDD = 1.8V, sampling frequency = 250 MSPS, sine wave input clock,
CLOAD = 5pF (2), RLOAD = 100Ω (3), LOW SPEED mode disabled, unless otherwise noted.
Min and max values are across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = 3.3V, DRVDD = 1.7V to
1.9V.
PARAMETER
ta
Aperture delay
tj
Aperture jitter
TEST CONDITIONS
The delay in time between the rising edge of the input sampling clock and
the actual time at which the sampling occurs
TYP
MAX
0.7
1.2
1.7
170
Wake-up time
ADC Latency (4)
DDR LVDS MODE
MIN
UNIT
ns
fs rms
Time to valid data after coming out of STANDBY mode
0.3
1
Time to valid data after coming out of PDN GLOBAL mode
25
100
Time to valid data after stopping and restarting the input clock
10
clock
cycles
Default, after reset
18
clock
cycles
0.8
1.2
ns
0.25
0.6
ns
µs
(5)
(6)
tsu
Data setup time
Data valid
th
Data hold time
Zero-crossing of CLKOUT to data becoming invalid (6)
tPDI
Clock propagation delay
Input clock rising edge cross-over to output clock rising edge cross-over
100 MSPS ≤ Sampling frequency ≤ 250 MSPS
tdelay
to zero-crossing of CLKOUTP
0.2 × ts + tdelay
5.0
6.2
ns
7.5
ns
LVDS bit clock duty cycle
Duty cycle of differential clock, (CLKOUTP–CLKOUTM)
100 MSPS ≤ Sampling frequency ≤ 250 MSPS
tRISE,
tFALL
Data rise time,
Data fall time
Rise time measured from –100 mV to 100 mV
Fall time measured from 100 mV to –100 mV
1 MSPS ≤ Sampling frequency ≤ 250 MSPS
0.08
0.14
0.2
ns
tCLKRISE,
tCLKFALL
Output clock rise time,
Output clock fall time
Rise time measured from –100 mV to 100 mV
Fall time measured from 100 mV to –100 mV
1 MSPS ≤ Sampling frequency ≤ 250 MSPS
0.08
0.14
0.2
ns
tOE
Output enable (OE) to data delay
Time to valid data after OE becomes active
52%
40
ns
PARALLEL CMOS MODE (7)
tSTART
Input clock to data delay
Input clock rising edge cross-over to start of data valid (8)
tDV
Data valid time
Time interval of valid data (8)
0.7
tPDI
Clock propagation delay
Input clock rising edge cross-over to output clock rising edge cross-over
100 MSPS ≤ Sampling frequency ≤ 150 MSPS
0.78 × ts + tdelay
tdelay
3.2
5
1.5
6.5
ns
ns
8
ns
Output clock duty cycle
Duty cycle of differential clock, (CLKOUT)
100 MSPS ≤ Sampling frequency ≤ 150 MSPS
tRISE,
tFALL
Data rise time,
Data fall time
Rise time measured from 20% to 80% of DRVDD,
Fall time measured from 80% to 20% of DRVDD,
1 MSPS ≤ Sampling frequency ≤ 250 MSPS
0.7
1.2
2
ns
tCLKRISE,
tCLKFALL
Output clock rise time,
Output clock fall time
Rise time measured from 20% to 80% of DRVDD,
Fall time measured from 80% to 20% of DRVDD,
1 MSPS ≤ Sampling frequency ≤ 150 MSPS
0.5
1
1.5
ns
tOE
Output enable (OE) to data delay
Time to valid data after OE becomes active
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
10
50%
20
ns
Timing parameters are specified by design and characterization and not tested in production.
CLOAD is the effective external single-ended load capacitance between each output pin and ground
RLOAD is the differential load resistance between the LVDS output pair.
At higher frequencies, tPDI is greater than one clock period and overall latency = ADC latency + 1.
Measurements are done with a transmission line of 100Ω characteristic impedance between the device and the load. Setup and hold
time specifications take into account the effect of jitter on the output data and clock.
Data valid refers to LOGIC HIGH of +100mV and LOGIC LOW of –100mV.
For Fs> 150 MSPS, it is recommended to use external clock for data capture and NOT the device output clock signal (CLKOUT).
Data valid refers to LOGIC HIGH of 1.26V and LOGIC LOW of 0.54V.
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LVDS Timings at Lower Sampling Frequencies
SAMPLING FREQUENCY, MSPS
SETUP TIME, ns
HOLD TIME, ns
MIN
TYP
MIN
TYP
210
1.0
1.4
MAX
0.4
0.8
190
1.1
1.5
0.5
0.9
170
1.3
1.7
0.7
1.1
150
1.6
1.9
0.9
1.2
125
1.9
2.2
1.1
1.4
<100
Enable LOW SPEED mode
2.5
MAX
2.0
tPDI, ns
1 ≤ Fs ≤ 100,
Enable LOW SPEED mode
MIN
(1)
TYP
MAX
8.2
(1)
Ts = 1/Sampling frequency
CMOS Timings at Lower Sampling Frequencies
Timings specified with respect to input clock
SAMPLING FREQUENCY, MSPS
tSTART, ns
MIN
TYP
DATA VALID TIME, ns
MAX
MIN
TYP
210
1.7
1.6
2.4
190
0.4
2.2
3.0
170
5.1
2.4
3.6
150
4.8
3.0
4.3
MAX
Timings specified with respect to CLKOUT
SAMPLING FREQUENCY, MSPS
SETUP TIME, ns
MIN
TYP
150
2.0
125
2.9
<100
Enable LOW SPEED mode
5.0
HOLD TIME, ns
MAX
MIN
TYP
3.2
1.5
2.2
4
2.2
2.7
MAX
3.8
tPDI, ns
1 ≤ Fs ≤ 100
Enable LOW SPEED mode
MIN
(1)
TYP
MAX
14
(1)
Ts = 1/Sampling frequency
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N+4
N+3
N+2
N+1
Sample
N
N+20
N+19
N+18
Input
Signal
ta
Input
Clock
CLKP
CLKM
CLKOUTM
CLKOUTP
tsu
Output Data
DXP, DXM
E
E – Even Bits D0,D2,D4,...
O – Odd Bits D1,D3,D5, ...
O
E
O
N–18
E
O
N–17
E
O
N–16
E
tPDI
th
18 Clock Cycles*
DDR
LVDS
O
E
O
E
O
E
N–15
O
N
E
E
O
O
N+2
N+1
tPDI
CLKOUT
tsu
Parallel
CMOS
18 Clock Cycles*
Output Data
N–18
N–17
N–16
N–15
th
N–14
N–1
N
N+1
N+2
Then, overall latency = ADC latency + 1.
ADC latency is 14 clock cycles in low-latency mode.
T0105-09
Figure 2. Latency Diagram
12
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Input
Clock
CLKP
CLKM
tPDI
Output
Clock
CLKOUTP
CLKOUTM
tsu
th
tsu
Output
Data Pair
(1)
(2)
Dn
Dn_Dn+1_P,
Dn_Dn+1_M
th
Dn
(1)
Dn+1
(2)
– Bits D0, D2, D4,...
Dn+1 – Bits D1, D3, D5, ...
T0106-07
Figure 3. LVDS Mode Timing
Input
Clock
CLKM
CLKP
tPDI
Output
Clock
CLKOUT
th
tsu
Output
Data
Input
Clock
Dn
Dn*
CLKM
CLKP
tSTART
tDV
Output
Data
Dn
Dn*
*Dn – Bits D0, D1, D2, ...
T0107-05
Figure 4. CMOS Mode Timing
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DEVICE CONFIGURATION
ADS614X/2X can be configured independently using either parallel interface control or serial interface
programming.
PARALLEL CONFIGURATION ONLY
To put the device in parallel configuration mode, keep RESET tied to HIGH (DRVDD).
Now, pins DFS, MODE, SEN and SDATA can be used to directly control certain modes of the ADC. The device
can be easily configured by connecting the parallel pins to the correct voltage levels (as described in Table 3 to
Table 6. There is no need to apply reset.
In this mode, SEN and SDATA function as parallel interface control pins. Frequently used functions can be
controlled in this mode – standby, selection between LVDS/CMOS output format, internal/external reference,
two’s complement/straight binary output format and position of the output clock edge.
Table 1 briefly describes the modes controlled by the parallel pins.
Table 1. Parallel Pin Functions
PIN
TYPE OF
CONTROL
CONTROLS MODES
DFS
Analog
Data format and LVDS/CMOS output interface.
MODE (1)
Analog
Internal or external reference, low speed mode enable
SEN
Analog
CLKOUT edge programmability.
SDATA
Digital
Global power-down (ADC, internal references and output buffers are
powered down)
(1)
In the next generation pin-compatible ADC family, MODE will be converted to a digital control pin for
certain reserved functions. So, the selection of internal or external reference and low speed functions
will not be supported using MODE. In the system board using ADS61x9/x8, the MODE pin can be
routed to a digital controller. This will avoid board modification while migrating to the next generation
ADC.
SERIAL INTERFACE CONFIGURATION ONLY
To exercise this mode, first the serial registers have to be reset to their default values and RESET pin has to be
kept LOW.
SEN, SDATA and SCLK function as serial interface pins in this mode and can be used to access the internal
registers of the ADC.
The registers can be reset either by applying a pulse on RESET pin or by setting HIGH the <RESET> bit (D7 in
register 0x00). The serial interface section describes the register programming and register reset in more detail.
Since the parallel pins DFS and MODE are not to be used in this mode, they have to be tied to ground.
14
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CONFIGURATION USING BOTH THE SERIAL INTERFACE AND PARALLEL CONTROLS
For increased flexibility, an additional configuration mode is supported wherein a combination of serial interface
registers and parallel pin controls (DFS, MODE) can be used to configure the device.
To exercise this mode, the serial registers have to be reset to their default values and RESET pin has to be kept
LOW.
SEN, SDATA and SCLK function as serial interface pins in this mode and can be used to access the internal
registers of ADC. The registers can be reset either by applying a pulse on RESET pin or by setting HIGH the
<RESET> bit (D7 in register 0x00). The serial interface section describes the register programming and register
reset in more detail.
The parallel interface control pins DFS and MODE can be used and their function is determined by the
appropriate voltage levels as described in Table 3. The voltage levels can be easily derived, by using a resistor
string as illustrated with an example as shown in Figure 5.
Since some functions can be controlled using both the parallel pins and serial registers, the priority between the
two is determined by a Priority Table as shown in Table 2.
Table 2. Priority Between Parallel Pins and Serial Registers
FUNCTION
PRIORITY
Internal/External reference
MODE pin controls this selection ONLY if the register bits <REF> = 00, otherwise <REF> controls the
selection
Data format selection
LVDS or CMOS interface selection
DFS pin controls this selection ONLY if the register bits <DATA FORMAT> = 00, otherwise <DATA
FORMAT> controls the selection
DFS pin controls this selection ONLY if the register bits <LVDS CMOS> = 00, otherwise <LVDS
CMOS> controls the selection
DESCRIPTION OF PARALLEL PINS
Table 3. SDATA – DIGITAL CONTROL PIN
SDATA
0
AVDD
DESCRIPTION
Normal operation (default)
Global power-down. ADC, internal references and the output buffers are powered down.
Table 4. SEN – ANALOG CONTROL PIN (1)
SEN
0
(3/8)AVDD
LVDS: Setup time decreases by (4xTs/26), Hold time increases by (4xTs/26)
CMOS: Setup time increases by (9xTs/26), Hold time reduces by (9xTs/26)
(5/8)AVDD
LVDS: Setup time increases by (4xTs/26), Hold time reduces by (4xTs/26)
CMOS: Setup time increases by (3xTs/26), Hold time reduces by (3xTs/26)
AVDD
(1)
DESCRIPTION – Output Clock Edge Programmability
LVDS: Data and output clock transitions are aligned
CMOS: Setup time increases by (6xTs/26), Hold time reduces by (6xTs/26)
Default output clock position (Setup/hold timings of output data with respect to this clock position is specified in the
timing characteristics table).
Ts = 1/Sampling frequency
Table 5. DFS – ANALOG CONTROL PIN
DFS
0
DESCRIPTION
2s complement data and DDR LVDS output
(3/8)AVDD
2s complement data and parallel CMOS output
(5/8)AVDD
Offset binary data and parallel CMOS output
AVDD
Offset binary data and DDR LVDS output
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Table 6. MODE – ANALOG CONTROL PIN
MODE
DESCRIPTION
0
Internal reference, LOW SPEED mode disabled (for Fs > 100 MSPS)
(3/8)AVDD
External reference, LOW SPEED mode disabled (for Fs > 100 MSPS)
(5/8)AVDD
External reference, LOW SPEED mode enabled (for Fs ≤ 100 MSPS)
AVDD
Internal reference, LOW SPEED mode enabled (for Fs ≤ 100 MSPS)
AVDD
(5/8) AVDD
3R
(5/8) AVDD
GND
AVDD
2R
(3/8) AVDD
(3/8) AVDD
3R
To Parallel Pin
GND
S0321-01
Figure 5. Simple Scheme to Configure Parallel Pins SEN and SCLK
SERIAL INTERFACE
The ADC has a set of internal registers, which can be accessed by the serial interface formed by pins SEN
(Serial interface Enable), SCLK (Serial Interface Clock) and SDATA (Serial Interface Data).
Serial shift of bits into the device is enabled when SEN is low. Serial data SDATA is latched at every falling edge
of SCLK when SEN is active (low). The serial data is loaded into the register at every 16th SCLK falling edge
when SEN is low. In case the word length exceeds a multiple of 16 bits, the excess bits are ignored. Data can be
loaded in multiple of 16-bit words within a single active SEN pulse.
The first 8 bits form the register address and the remaining 8 bits are the register data. The interface can work
with SCLK frequency from 20 MHz down to low speeds (few Hertz) and also with non-50% SCLK duty cycle.
Register Initialization
After power-up, the internal registers MUST be initialized to their default values. This can be done in one of two
ways:
1. Either through hardware reset by applying a high-going pulse on RESET pin (of width greater than 10ns) as
shown in Figure 6.
OR
2. By applying software reset. Using the serial interface, set the <RESET> bit (D7 in register 0x00) to HIGH.
This initializes internal registers to their default values and then self-resets the <RESET> bit to LOW. In this
case the RESET pin is kept LOW.
16
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Register Data
Register Address
SDATA
A7
A6
A5
A4
A3
A2
A1
A0
D7
D6
t(SCLK)
D5
D4
D3
D2
D1
D0
t(DH)
t(DSU)
SCLK
t(SLOADH)
t(SLOADS)
SEN
RESET
T0109-01
Figure 6. Serial Interface Timing
SERIAL INTERFACE TIMING CHARACTERISTICS
Typical values at 25°C, min and max values across the full temperature range
TMIN = –40°C to TMAX = 85°C, AVDD = 3.3V, DRVDD = 1.8V, unless otherwise noted.
PARAMETER
MIN
> DC
TYP
MAX
UNIT
20
MHz
fSCLK
SCLK frequency (= 1/ tSCLK)
tSLOADS
SEN to SCLK setup time
25
ns
tSLOADH
SCLK to SEN hold time
25
ns
tDS
SDATA setup time
25
ns
tDH
SDATA hold time
25
ns
SERIAL REGISTER READOUT
The device includes an option where the contents of the internal registers can be read back. This may be useful
as a diagnostic check to verify the serial interface communication between the external controller and the ADC.
a. First, set register bit <SERIAL READOUT> = 1. This also disables any further writes into the registers
(EXCEPT register bit <SERIAL READOUT> itself).
b. Initiate a serial interface cycle specifying the address of the register (A7-A0) whose content has to be read.
c. The device outputs the contents (D7-D0) of the selected register on OVR_SDOUT pin.
d. The external controller can latch the contents at the falling edge of SCLK.
e. To enable register writes, reset register bit <SERIAL READOUT> = 0.
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A) Enable serial readout (<SERIAL READOUT> = 1)
Register Data (D7:D0) = 0x01
Register Address (A7:A0) = 0x00
SDATA
0
0
0
0
0
0
0
0
D7
D6
D5
D4
D3
D2
D1
D0
SCLK
SEN
Pin OVR_SDOUT functions as OVR (<SERIAL READOUT> = 0)
OVR_SDOUT
B) Read contents of register 0x3F. This register has been initialized with 0x04 (device is put in global power down mode)
Register Data (D7:D0) = XX (Don't Care)
Register Address (A7:A0) = 0x3F
SDATA
A7
A6
A5
A4
A3
A2
A1
A0
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
0
1
0
0
SCLK
SEN
OVR_SDOUT
Pin OVR_SDOUT functions as serial readout (<SERIAL READOUT> = 1)
T0386-01
Figure 7. Serial Readout
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RESET TIMING
Typical values at 25°C, min and max values across the full temperature range
TMIN = –40°C to TMAX = 85°C, unless otherwise noted.
PARAMETER
t1
t2
Power-on delay
Reset pulse width
t3
TEST CONDITIONS
MIN
TYP
Delay from power-up of AVDD and DRVDD to RESET pulse active
MAX
UNIT
1
ms
10
Pulse width of active RESET signal that will reset the serial registers
ns
µs
1
Delay from RESET disable to SEN active
100
ns
Power Supply
AVDD, DRVDD
t1
RESET
t2
t3
SEN
T0108-01
Figure 8. Reset Timing Diagram
SERIAL REGISTER MAP
Table 7. Summary of Functions Supported by Serial Interface (1)
REGISTER ADDRESS
REGISTER FUNCTIONS
A7–A0 IN HEX
D7
D6
D5
D4
D3
D2
D1
D0
00
<RESET>
Software
Reset
0
0
0
0
0
0
<SERIAL
READOUT>
20
0
0
0
0
0
<ENABLE
LOW SPEED
MODE>
0
0
3F
0
0
0
<PDN
GLOBAL>
<STANDBY>
<PDN
OBUF>
0
0
0
0
0
0
0
REF>
Internal or external reference
<LVDS CMOS>
Output interface
41
<CLKOUT POSN>
Output clock position control
44
50
0
0
52
0
0
53
0
ENABLE OFFSET CORR>
51
0
0
0
<DATA FORMAT>
2s complement or offset
binary
0
<CUSTOM PATTERN LOW>
55
(1)
0
CUSTOM PATTERN HIGH>
0
0
0
<FINE GAIN >
62
0
0
63
0
0
0
0
0
<OFFSET CORR TIME CONSTANT>
Offset correction time constant
0
0
0
TEST PATTERNS>
PROGRAM OFFSET PEDESTAL >
Multiple functions in a register can be programmed in a single write operation.
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DESCRIPTION OF SERIAL REGISTERS
A)
A7–A0 IN HEX
D7
<RESET>
Software Reset
00
D7
D6
D5
0
D4
0
D3
0
0
D2
0
D1
D0
0
<SERIA
L
READO
UT>
<RESET>
1
Software reset applied – resets all internal registers and self-clears to 0.
D0
<SERIAL READOUT>
0
Serial readout disabled
1
Serial readout enabled, Pin OVR_SDOUT functions as serial data readout.
A)
A7–A0 IN HEX
D7
20
D2
D6
0
D5
0
D4
0
0
D3
D2
D1
D0
0
<ENABLE
LOW SPEED
MODE>
0
0
D3
D2
D1
D0
0
<PDN
GLOBAL>
<STANDBY>
<PDN
OBUF>
<ENABLE LOW SPEED MODE>
0
LOW SPEED mode disabled. Use for sampling frequency > 100 MSPS
1
Enable LOW SPEED mode for sampling frequencies ≤ 100 MSPS.
B)
A7–A0 IN HEX
3F
D0
D7
D6
0
D5
D4
<REF>
0
<PDN OBUF> Power down output buffer
0
Output buffer enabled
1
Output buffer powered down
D1
<STANDBY>
0
Normal operation
1
ADC alone powered down. Internal references, output buffers are active. Quick wake-up time
D2
<PDN GLOBAL>
0
Normal operation
1
Total power down – ADC, internal references and output buffers are powered down. Slow wake-up time.
D6,D5
<REF> Internal or external reference selection
00
MODE pin controls reference selection
01
Internal reference enabled
11
External reference enabled
C)
A7–A0 IN HEX
41
D7,D6
20
D7
D6
<LVDS CMOS>
D5
D4
D3
D2
D1
D0
0
0
0
0
0
0
<LVDS CMOS>
00
DFS pin controls LVDS or CMOS interface selection
10
DDR LVDS interface
11
Parallel CMOS interface
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D)
A7–A0 IN HEX
D7
D6
44
D5
D4
D3
D2
<CLKOUT POSN> Output clock position control
D1
D0
0
0
LVDS Interface
D7-D5
<CLKOUT POSN> Output clock rising edge position
000
Default output clock position (refer to timing specification table)
100
Default output clock position (refer to timing specification table)
101
Rising edge shifted by + (4/26)Ts
110
Rising edge aligned with data transition
111
Rising edge shifted by - (4/26)Ts
D4-D2
<CLKOUT POSN> Output clock falling edge position
000
Default output clock position (refer to timing specification table)
100
Default output clock position (refer to timing specification table)
101
Falling edge shifted by + (4/26)Ts
110
Falling edge aligned with data transition
111
Falling edge shifted by - (4/26)Ts
CMOS Interface
D7-D5
<CLKOUT POSN> Output clock rising edge position
000
Default output clock position (refer to timing specification table)
100
Default output clock position (refer to timing specification table)
101
Rising edge shifted by + (4/26)Ts
110
Rising edge shifted by + (6/26)Ts
111
Rising edge aligned with data transition
D4-D2
<CLKOUT POSN> Output clock falling edge position
000
Default output clock position (refer to timing specification table)
100
Default output clock position (refer to timing specification table)
101
Falling edge shifted by + (4/26)Ts
110
Falling edge shifted by + (6/26)Ts
111
Falling edge aligned with data transition
Ts = 1/Sampling Frequency
E)
A7–A0 IN HEX
D7
D6
D5
D4
D3
50
0
0
0
0
0
D2,D1
D2
D1
<DATA FORMAT> 2s complement or offset binary
D0
0
<DATA FORMAT>
00
DFS pin controls data format selection
10
2's complement
11
Offset binary
F)
A7–A0 IN HEX
D7
D6
51
D5
D4
D3
D2
D1
D0
<Custom Pattern>
52
0
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0
<Custom Pattern>
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D7–D0
<CUSTOM LOW>
8 lower bits of custom pattern available at the output instead of ADC data.
D5–D0
<CUSTOM HIGH>
6 upper bits of custom pattern available at the output instead of ADC data
G)
A7–A0 IN HEX
D7
D6
D5
D4
D3
D2
D1
D0
53
0
<ENABLE OFFSET CORR>
Offset correction enable
0
0
0
0
0
0
D6
<ENABLE OFFSET CORR>
0
Offset correction disabled
1
Offset correction enabled
H)
A7–A0 IN HEX
D7
55
D3–D0
D6
D5
<FINE GAIN>
D4
D3
D2
D1
D0
<OFFSET CORR TC> Offset correction time
constant
<OFFSET CORR TC> Time constant of correction loop in number of clock cycles. See "Offset Correction" in application
section.
0000
256 k
0001
512 k
0010
1M
0011
2M
0100
4M
0101
8M
0110
16 M
0111
32 M
1000
64 M
1001
128 M
1010
256 M
1011
512 M
1100 to 1111 RESERVED
D7–D4
22
<FINE GAIN> Gain programmability in 0.5 dB steps
0000
0 dB gain, default after reset
0001
0.5 dB gain
0010
1.0 dB gain
0011
1.5 dB gain
0100
2.0 dB gain
0101
2.5 dB gain
0110
3.0 dB gain
0111
3.5 dB gain
1000
4.0 dB gain
1001
4.5 dB gain
1010
5.0 dB gain
1011
5.5 dB gain
1100
6.0 dB gain
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I)
D2–D0
A7–A0 IN HEX
D7
D6
D5
D4
D3
62
0
0
0
0
0
D2
D1
D0
<TEST PATTERNS>
<TEST PATTERNS> Test Patterns to verify data capture
000
Normal operation
001
Outputs all zeros
010
Outputs all ones
011
Outputs toggle pattern
ADS6149/8: Output data <D13:D0> alternates between 10101010101010 and 01010101010101 every clock cycle.
ADS6129/8: Output data <D11:D0> alternates between 101010101010 and 010101010101 every clock cycle.
100
Outputs digital ramp
ADS6149/8: Output data increments by one LSB (14-bit) every clock cycle from code 0 to code 16383
ADS6129/8: Output data increments by one LSB (124-bit) every 4th clock cycle from code 0 to code 4095
101
Outputs custom pattern as specified in registers 0x51 and 0x52.
110
Unused
111
Unused
J)
A7–A0 IN HEX
D7
63
D5–D0
D6
D5
D4
D3
D2
D1
D0
<OFFSET PEDESTAL>
<OFFSET PEDESTAL> When the offset correction is enabled, the final converged value after the offset is corrected will be
the ADC mid-code value.
A pedestal can be added to the final converged value by programming these bits. For example, See "Offset Correction" in
application section.
011111
Mid-code + 31 LSB
011110
Mid-code + 30 LSB
011101
Mid-code + 29 LSB
....
000000
Mid-code
111111
Mid-code - 1 LSB
111110
Mid-code - 2 LSB
....
100000
Mid-code - 32 LSB
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D12_D13_M
D10_D11_P
D10_D11_M
D8_D9_P
D8_D9_M
D6_D7_P
D6_D7_M
D4_D5_P
D4_D5_M
D2_D3_P
D2_D3_M
47
45
44
43
42
41
40
39
38
37
1
46
DRGND
48
D12_D13_P
DEVICE INFORMATION
Pad is connected to DRGND
36
DRGND
35
DRVDD
DRVDD
2
OVR_SDOUT
3
34
D0_D1_P
CLKOUTM
4
33
D0_D1_M
CLKOUTP
5
32
NC
DFS
6
31
NC
Thermal Pad
22
23
24
AVDD
MODE
AVDD
21
NC
AGND
20
AVDD
25
AVDD
26
12
18
11
19
CLKM
AGND
AVDD
SEN
AGND
27
17
10
AGND
CLKP
16
SDATA
INM
SCLK
28
14
29
9
15
AVDD
AGND
INP
RESET
AGND
30
8
13
7
VCM
OE
P0023-12
D10_D11_M
D8_D9_P
D8_D9_M
D6_D7_P
D6_D7_M
D4_D5_P
D4_D5_M
D2_D3_P
D2_D3_M
D0_D1_P
D0_D1_M
47
45
44
43
42
41
40
39
38
37
1
46
DRGND
48
D10_D11_P
Figure 9. PIN CONFIGURATION (LVDS MODE) — ADS6149/48
Pad is connected to DRGND
36
DRGND
35
DRVDD
DRVDD
2
OVR_SDOUT
3
34
NC
CLKOUTM
4
33
NC
CLKOUTP
5
32
NC
DFS
6
31
NC
Thermal Pad
OE
7
30
RESET
22
23
24
AVDD
AVDD
21
NC
MODE
20
AVDD
AGND
18
AGND
19
AVDD
25
AVDD
26
12
AGND
11
17
CLKM
AGND
SEN
16
27
INM
10
14
CLKP
15
SDATA
INP
SCLK
28
AGND
29
9
13
8
VCM
AVDD
AGND
P0023-13
Figure 10. PIN CONFIGURATION (LVDS MODE) — ADS6129/28
24
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Table 8. PIN ASSIGNMENTS (LVDS MODE) — ADS6149/48 and ADS6129/28
PIN
NAME
NO.
I/O
NO.
of
PINS
DESCRIPTION
AVDD
8, 18, 20,
22, 24, 26
I
6
3.3-V Analog power supply
AGND
9, 12, 14,
17, 19, 25
I
6
Analog ground
CLKP, CLKM
10, 11
I
2
Differential clock input
INP, INM
15, 16
I
2
Differential analog input
13
IO
1
Internal reference mode – Common-mode voltage output.
VCM
External reference mode – Reference input. The voltage forced on this pin sets the internal
references
Serial interface RESET input.
RESET
30
I
1
SCLK
29
I
1
When using the serial interface mode, the user MUST initialize internal registers through hardware
RESET by applying a high-going pulse on this pin or by using software reset option. Refer to
SERIAL INTERFACE section.
In parallel interface mode, the user has to tie RESET pin permanently HIGH. (SDATA and SEN
are used as parallel pin controls in this mode)
The pin has an internal 100 kΩ pull-down resistor.
Serial interface clock input. The pin has an internal 100 kΩ pull-down resistor.
This pin functions as serial interface data input when RESET is LOW. It functions as power down control pin
when RESET is tied high.
SDATA
28
I
1
See Table 3 for detailed information.
The pin has an internal 100 kΩ pull-down resistor.
This pin functions as serial interface enable input when RESET is low.
It functions as output clock edge control when RESET is tied high. See Table 4 for detailed
information.
The pin has an internal 100 kΩ pull-up resistor to AVDD.
SEN
27
I
1
OE
7
I
1
Output buffer enable input, active high. The pin has an internal 100 kΩ pull-up resistor to AVDD.
DFS
6
I
1
Data Format Select input. This pin sets the DATA FORMAT (2s complement or Offset binary) and the
LVDS/CMOS output interface type.
See Table 5 for detailed information.
23
I
1
Internal or external reference selection and low speed mode control. control. See Table 6 for detailed
information.
CLKOUTP
5
O
1
Differential output clock, true
CLKOUTM
4
O
1
Differential output clock, complement
D0_D1_P
O
1
Differential output data D0 and D1 multiplexed, true
D0_D1_M
O
1
Differential output data D0 and D1 multiplexed, complement
D2_D3_P
O
1
Differential output data D2 and D3 multiplexed, true
D2_D3_M
O
1
Differential output data D2 and D3 multiplexed, complement
D4_D5_P
O
1
Differential output data D4 and D5 multiplexed, true
D4_D5_M
O
1
Differential output data D4 and D5 multiplexed, complement
O
1
Differential output data D6 and D7 multiplexed, true
O
1
Differential output data D6 and D7 multiplexed, complement
O
1
Differential output data D8 and D9 multiplexed, true
D8_D9_M
O
1
Differential output data D8 and D9 multiplexed, complement
D10_D11_P
O
1
Differential output data D10 and D11 multiplexed, true
D10_D11_M
O
1
Differential output data D10 and D11 multiplexed, complement
D12_D13_P
O
1
Differential output data D12 and D13 multiplexed, true
D12_D13_M
O
1
Differential output data D12 and D13 multiplexed, complement
O
1
It is a CMOS output with logic levels determined by DRVDD supply. It functions as out-of-range indicator after
reset and when register bit <SERIAL READOUT> = 0. It functions as serial register readout pin when register bit
<SERIAL READOUT> = 1.
MODE
(1)
D6_D7_P
D6_D7_M
D8_D9_P
OVR_SDOUT
(1)
See
Figure 9
and
Figure 10
3
In the next generation pin-compatible ADC family, MODE will be converted to a digital control pin for certain reserved functions. So, the
selection of internal or external reference and low speed functions will not be supported using MODE. In the system board using
ADS61x9/x8, the MODE pin can be routed to a digital controller. This will avoid board modification while migrating to the next generation
ADC.
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Table 8. PIN ASSIGNMENTS (LVDS MODE) — ADS6149/48 and ADS6129/28 (continued)
PIN
NAME
NO.
I/O
NO.
of
PINS
DESCRIPTION
DRVDD
2, 35
I
2
1.8 V Digital and output buffer supply
DRGND
1, 36, PAD
I
2
Digital and output buffer ground
NC
26
See
Figure 9
and
Figure 10
Do not connect
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D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
46
45
44
43
42
41
40
39
38
37
D13
1
48
DRGND
47
www.ti.com ..................................................................................................................................................... SLWS211B – JULY 2008 – REVISED OCTOBER 2008
Pad is connected to DRGND
36
DRGND
35
DRVDD
DRVDD
2
OVR_SDOUT
3
34
D1
UNUSED
4
33
D0
CLKOUT
5
32
NC
DFS
6
31
NC
Thermal Pad
22
23
24
MODE
AVDD
AGND
AVDD
25
21
12
NC
AGND
20
AVDD
AVDD
SEN
26
18
27
11
19
CLKP
CLKM
AVDD
SDATA
AGND
28
10
17
9
AGND
AGND
16
SCLK
INM
29
15
8
INP
AVDD
13
RESET
14
30
VCM
7
AGND
OE
P0023-14
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
46
45
44
43
42
41
40
39
38
37
D11
1
48
DRGND
47
Figure 11. PIN CONFIGURATION (CMOS MODE) – ADS6149/48
Pad is connected to DRGND
36
DRGND
DRVDD
2
35
DRVDD
OVR_SDOUT
3
34
NC
UNUSED
4
33
NC
CLKOUT
5
32
NC
DFS
6
31
NC
Thermal Pad
23
24
MODE
AVDD
AGND
22
25
AVDD
12
21
AGND
NC
AVDD
20
26
AVDD
11
18
CLKM
19
SEN
AVDD
27
AGND
10
17
CLKP
AGND
SDATA
16
28
INM
9
15
AGND
INP
SCLK
13
RESET
29
14
30
8
VCM
7
AGND
OE
AVDD
P0023-15
Figure 12. PIN CONFIGURATION (CMOS MODE) – ADS6129/28
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PIN ASSIGNMENTS (CMOS MODE) – ADS6149/48 and ADS6129/28
PIN
NAME
NO.
I/O
NO. of
PINS
DESCRIPTION
AVDD
8, 18, 20,
22, 24, 26
I
6
AGND
9, 12, 14,
17, 19, 25
I
6
CLKP, CLKM
10, 11
I
2
Differential clock input
INP, INM
15, 16
I
2
Differential analog input
13
IO
1
Internal reference mode – Common-mode voltage output.
External reference mode – Reference input. The voltage forced on this pin sets the internal
references
VCM
3.3-V Analog power supply
Analog ground
RESET
30
I
1
Serial interface RESET input.
When using the serial interface mode, the user MUST initialize internal registers through
hardware RESET by applying a high-going pulse on this pin or by using software reset option.
Refer to SERIAL INTERFACE section.
In parallel interface mode, the user has to tie RESET pin permanently HIGH. (SDATA and SEN
are used as parallel pin controls in this mode)
The pin has an internal 100 kΩ pull-down resistor.
SCLK
29
I
1
Serial interface clock input. The pin has an internal 100 kΩ pull-down resistor.
1
This pin functions as serial interface data input when RESET is LOW. It functions as power down
control pin when RESET is tied high.
See Table 3 for detailed information.
The pin has an internal 100 kΩ pull-down resistor.
SDATA
28
I
SEN
27
I
1
This pin functions as serial interface enable input when RESET is low.
It functions as output clock edge control when RESET is tied high. See Table 4 for detailed
information.
The pin has an internal 100 kΩ pull-up resistor to AVDD.
DFS
6
I
1
Data Format Select input. This pin sets the DATA FORMAT (2s complement or Offset binary)
and the LVDS/CMOS output interface type.
See Table 5 for detailed information.
MODE
23
I
1
Internal or external reference selection control and low speed mode control. See Table 6 for
detailed information.
CLKOUT
5
O
1
CMOS output clock
OE
7
I
1
Output buffer enable input, active high. The pin has an internal 100 kΩ pull-up resistor to AVDD.
CLKOUTM
4
O
1
Differential output clock, complement
See
Figure 11
and
Figure 12
O
14/12
3
O
1
It is a CMOS output with logic levels determined by DRVDD supply. It functions as out-of-range
indicator after reset and when register bit <SERIAL READOUT> = 0. It functions as serial
register readout pin when <SERIAL READOUT> = 1.
DRVDD
2, 35
I
2
1.8 V Digital and output buffer supply
DRGND
1, 36, PAD
I
2
Digital and output buffer ground
UNUSED
4
1
Unused pin in CMOS mode
D0–D13
OVR_SDOUT
NC
28
See
Figure 11
and
Figure 12
14 bit/12 bit CMOS output data
Do not connect
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TYPICAL CHARACTERISTICS - ADS6149
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface, 32K point FFT (unless otherwise noted)
FFT for 20 MHz INPUT SIGNAL
FFT for 60 MHz INPUT SIGNAL
0
0
SFDR = 94.6 dBc
SINAD = 73.3 dBFS
SNR = 73.4 dBFS
THD = 90.2 dBc
−20
−40
Amplitude − dB
Amplitude − dB
−40
SFDR = 87.7 dBc
SINAD = 72.7 dBFS
SNR = 73 dBFS
THD = 84 dBc
−20
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
25
50
75
100
f − Frequency − MHz
125
0
25
50
G001
Figure 13.
FFT for 170 MHz INPUT SIGNAL
125
G002
FFT for 300 MHz INPUT SIGNAL
0
SFDR = 81.8 dBc
SINAD = 70.8 dBFS
SNR = 71.3 dBFS
THD = 79.7 dBc
−20
SFDR = 76.3 dBc
SINAD = 68.1 dBFS
SNR = 69.1 dBFS
THD = 73.8 dBc
−20
−40
Amplitude − dB
−40
Amplitude − dB
100
Figure 14.
0
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
25
50
75
100
f − Frequency − MHz
125
0
25
50
G003
G004
fIN1 = 185.1 MHz, –36 dBFS
fIN2 = 190.1 MHz, –36 dBFS
2-Tone IMD = –105 dBFS
SFDR = –103 dBFS
−20
−40
Amplitude − dB
−40
125
FFT for 2-TONE INPUT SIGNAL (IMD)
0
fIN1 = 185.1 MHz, –7 dBFS
fIN2 = 190.1 MHz, –7 dBFS
2-Tone IMD = –90.6 dBFS
SFDR = –91 dBFS
−20
100
Figure 16.
FFT for 2-TONE INPUT SIGNAL (IMD)
0
75
f − Frequency − MHz
Figure 15.
Amplitude − dB
75
f − Frequency − MHz
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
25
50
75
f − Frequency − MHz
100
125
G005
0
25
50
Figure 17.
Copyright © 2008, Texas Instruments Incorporated
75
100
f − Frequency − MHz
125
G006
Figure 18.
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TYPICAL CHARACTERISTICS - ADS6149 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface, 32K point FFT (unless otherwise noted)
SFDR
vs
INPUT FREQUENCY
SNR
vs
INPUT FREQUENCY
100
74
95
73
LVDS
72
85
SNR − dBFS
SFDR − dBc
90
80
75
70
CMOS
LVDS
70
69
68
65
67
60
66
55
65
50
CMOS
64
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
G007
Figure 19.
Figure 20.
SFDR
vs
GAIN
SINAD
vs
GAIN
100
90
SINAD − dBFS
5 dB
80
75
6 dB
70
2 dB
60
0 dB
69
67
65
3 dB
63
4 dB
5 dB
61
6 dB
59
1 dB
55
1 dB
71
4 dB
85
2 dB
73
3 dB
65
57
0 dB
50
Input adjusted to get −1dBFS input
55
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
G009
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
Figure 21.
30
G008
75
Input adjusted to get −1dBFS input
95
SFDR − dBc
71
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G010
Figure 22.
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www.ti.com ..................................................................................................................................................... SLWS211B – JULY 2008 – REVISED OCTOBER 2008
TYPICAL CHARACTERISTICS - ADS6149 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface, 32K point FFT (unless otherwise noted)
PERFORMANCE
vs
INPUT AMPLITUDE
PERFORMANCE
vs
INPUT COMMON-MODE VOLTAGE
110
78
75
70
74
SNR (dBFS)
60
73
50
72
−40
fIN = 60 MHz
−30
−20
−10
SNR
84
73
72
80
1.35
70
1.40
1.45
1.50
1.55
1.60
Figure 24.
PERFORMANCE
vs
AVDD SUPPLY
PERFORMANCE
vs
DRVDD SUPPLY
78
fIN = 60.1 MHz
DRVDD = 1.8 V
92
90
92
78
fIN = 60.1 MHz
AVDD = 3.3 V
90
76
88
76
86
75
75
74
86
G012
77
SFDR
88
71
1.65
VCM − Common-Mode Voltage of Analog Inputs − V
G011
Figure 23.
96
SFDR − dBc
74
82
0
Input Amplitude − dBFS
94
86
73
77
SFDR
84
74
SNR
82
73
SNR − dBFS
−50
75
71
SFDR (dBc)
SFDR − dBc
30
−60
88
SNR − dBFS
80
SFDR − dBc
76
SFDR
SNR − dBFS
90
40
76
77
SNR − dBFS
SFDR − dBc, dBFS
100
90
fIN = 60 MHz
SFDR (dBFS)
SNR
84
72
80
72
82
71
78
71
80
2.9
3.0
3.1
3.2
3.3
3.4
3.5
AVDD − Supply Voltage − V
3.6
70
3.7
76
1.6
G013
1.7
1.8
70
2.0
DRVDD − Supply Voltage − V
Figure 25.
Copyright © 2008, Texas Instruments Incorporated
1.9
G014
Figure 26.
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TYPICAL CHARACTERISTICS - ADS6149 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface, 32K point FFT (unless otherwise noted)
PERFORMANCE
vs
TEMPERATURE
PERFORMANCE
vs
INPUT CLOCK AMPLITUDE
77
94
fIN = 60 MHz
92
76
77
74
84
73
SFDR − dBc
86
SNR
82
72
80
−40
71
−20
0
20
40
60
88
75
86
74
SNR
84
73
82
72
80
71
78
0.20
80
T − Temperature − °C
76
SFDR
75
SFDR
SNR − dBFS
SFDR − dBc
90
88
70
0.70
1.20
1.70
2.20
Figure 28.
PERFORMANCE
vs
INPUT CLOCK DUTY CYCLE
PERFORMANCE
vs
VCM VOLTAGE
76
fIN = 60 MHz
External Reference Mode
76
88
74
SNR
80
73
76
72
72
35
40
45
50
55
60
65
74
84
73
82
80
1.30
70
Input Clock Duty Cycle − %
86
SNR
71
30
SFDR − dBc
84
SNR − dBFS
SFDR − dBc
75
75
SFDR
SFDR
88
G016
90
77
fIN = 5 MHz
92
2.70
Input Clock Amplitude − VPP
G015
Figure 27.
96
SNR − dBFS
90
78
fIN = 60 MHz
SNR − dBFS
92
72
1.35
G017
1.40
1.45
1.50
1.55
VVCM − VCM Voltage − V
Figure 29.
1.60
1.65
71
1.70
G018
Figure 30.
OUTPUT NOISE HISTOGRAM
40
RMS (LSB) = 0.995
35
Occurence − %
30
25
20
15
10
5
0
8203 8204 8205 8206 8207 8208 8209 8210 8211 8212
Output Code
G019
Figure 31.
32
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www.ti.com ..................................................................................................................................................... SLWS211B – JULY 2008 – REVISED OCTOBER 2008
TYPICAL CHARACTERISTICS - ADS6148
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
FFT for 20 MHz INPUT SIGNAL
FFT for 60 MHz INPUT SIGNAL
0
0
SFDR = 90.75 dBc
SINAD = 73.13 dBFS
SNR = 73.25 dBFS
THD = 87.76 dBc
−20
−40
Amplitude − dB
Amplitude − dB
−40
SFDR = 92.3 dBc
SINAD = 72.9 dBFS
SNR = 73 dBFS
THD = 89 dBc
−20
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
20
40
60
80
100
f − Frequency − MHz
0
20
40
G020
Figure 32.
FFT for 170 MHz INPUT SIGNAL
100
G021
FFT for 300 MHz INPUT SIGNAL
0
SFDR = 82.44 dBc
SINAD = 70.81 dBFS
SNR = 71.17 dBFS
THD = 80.89 dBc
−20
SFDR = 76.3 dBc
SINAD = 68.5 dBFS
SNR = 69.3 dBFS
THD = 75.1 dBc
−20
−40
Amplitude − dB
−40
Amplitude − dB
80
Figure 33.
0
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
20
40
60
80
100
f − Frequency − MHz
0
20
40
60
80
100
f − Frequency − MHz
G022
Figure 34.
G023
Figure 35.
FFT for 2-TONE INPUT SIGNAL (IMD)
FFT for 2-TONE INPUT SIGNAL (IMD)
0
0
fIN1 = 185.1 MHz, –7 dBFS
fIN2 = 190.1 MHz, –7 dBFS
2-Tone IMD = –90 dBFS
SFDR = –88 dBFS
−20
fIN1 = 185.1 MHz, –36 dBFS
fIN2 = 190.1 MHz, –36 dBFS
2-Tone IMD = –101 dBFS
SFDR = –97 dBFS
−20
−40
Amplitude − dB
−40
Amplitude − dB
60
f − Frequency − MHz
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
20
40
60
f − Frequency − MHz
80
100
0
G024
20
40
Figure 36.
Copyright © 2008, Texas Instruments Incorporated
60
80
100
f − Frequency − MHz
G025
Figure 37.
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33
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ADS6148/ADS6128
SLWS211B – JULY 2008 – REVISED OCTOBER 2008 ..................................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS - ADS6148 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
SFDR
vs
INPUT FREQUENCY
100
74
95
73
90
72
LVDS
85
SNR − dBFS
SFDR − dBc
SNR
vs
INPUT FREQUENCY
80
CMOS
75
70
69
CMOS
68
67
60
66
55
65
64
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
G026
Figure 38.
Figure 39.
SFDR
vs
GAIN
SINAD
vs
GAIN
100
SINAD − dBFS
80
5 dB
75
6 dB
70
2 dB
65
3 dB
71
4 dB
85
2 dB
73
3 dB
90
69
67
65
4 dB
63
5 dB
61
60
6 dB
59
1 dB
55
1 dB
57
0 dB
50
Input adjusted to get −1dBFS input
0 dB
55
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
G028
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
Figure 40.
34
G027
75
Input adjusted to get −1dBFS input
95
SFDR − dBc
70
65
50
LVDS
71
Submit Documentation Feedback
G029
Figure 41.
Copyright © 2008, Texas Instruments Incorporated
Product Folder Link(s): ADS6149/ADS6129 ADS6148/ADS6128
ADS6149/ADS6129
ADS6148/ADS6128
www.ti.com ..................................................................................................................................................... SLWS211B – JULY 2008 – REVISED OCTOBER 2008
TYPICAL CHARACTERISTICS - ADS6148 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
PERFORMANCE
vs
INPUT AMPLITUDE
PERFORMANCE
vs
INPUT COMMON-MODE VOLTAGE
110
78
80
75
SNR (dBFS)
74
60
73
50
72
94
75
SFDR
92
74
SNR
90
73
88
SFDR (dBc)
fIN = 60 MHz
−50
−40
−30
−20
−10
70
Input Amplitude − dBFS
77
75
88
74
SNR
86
73
84
82
3.3
3.4
3.5
AVDD − Supply Voltage − V
94
76
90
3.6
G031
78
fIN = 60.1 MHz
AVDD = 3.3 V
77
SFDR
92
76
90
75
88
74
SNR
86
73
72
84
72
71
82
71
70
3.7
80
1.6
G032
1.7
1.8
1.9
70
2.0
DRVDD − Supply Voltage − V
Figure 44.
Copyright © 2008, Texas Instruments Incorporated
71
1.65
96
SFDR − dBc
SFDR − dBc
1.60
PERFORMANCE
vs
DRVDD SUPPLY
SFDR
3.2
1.55
PERFORMANCE
vs
AVDD SUPPLY
78
3.1
1.50
VCM − Common-Mode Voltage of Analog Inputs − V
G030
fIN = 60.1 MHz
DRVDD = 1.8 V
3.0
1.45
Figure 43.
92
80
2.9
1.40
Figure 42.
96
94
86
1.35
0
SNR − dBFS
30
−60
72
71
SNR − dBFS
40
SNR − dBFS
76
SFDR − dBc
90
70
76
77
SNR − dBFS
SFDR − dBc, dBFS
100
96
fIN = 60.1 MHz
SFDR (dBFS)
G033
Figure 45.
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35
ADS6149/ADS6129
ADS6148/ADS6128
SLWS211B – JULY 2008 – REVISED OCTOBER 2008 ..................................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS - ADS6148 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
PERFORMANCE
vs
TEMPERATURE
PERFORMANCE
vs
INPUT CLOCK AMPLITUDE
96
90
94
76
SFDR
78
fIN = 60 MHz
77
86
74
84
73
SNR
82
72
80
−40
71
−20
0
20
40
60
90
88
86
73
84
72
82
71
1.70
2.20
Figure 47.
PERFORMANCE
vs
INPUT CLOCK DUTY CYCLE
PERFORMANCE
vs
VCM VOLTAGE
75
84
74
SNR
80
73
76
72
72
94
50
55
60
65
SFDR
92
74
90
73
86
1.30
70
Input Clock Duty Cycle − %
75
SNR
88
71
45
SFDR − dBc
SFDR
76
fIN = 60.1 MHz
External Reference Mode
76
88
G035
96
SNR − dBFS
92
SFDR − dBc
1.20
Input Clock Amplitude − VPP
77
40
70
0.70
G034
fIN = 5 MHz
35
74
SNR
Figure 46.
96
30
75
80
0.20
80
T − Temperature − °C
76
SFDR
SFDR − dBc
75
SNR − dBFS
SFDR − dBc
92
88
SNR − dBFS
77
fIN = 60.1 MHz
1.35
G036
1.40
1.45
72
1.50
1.55
VVCM − VCM Voltage − V
Figure 48.
SNR − dBFS
92
1.60
1.65
71
1.70
G037
Figure 49.
OUTPUT NOISE HISTOGRAM
40
RMS (LSB) = 1
35
Occurence − %
30
25
20
15
10
5
0
8203 8204 8205 8206 8207 8208 8209 8210 8211 8212
Output Code
G038
Figure 50.
36
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ADS6149/ADS6129
ADS6148/ADS6128
www.ti.com ..................................................................................................................................................... SLWS211B – JULY 2008 – REVISED OCTOBER 2008
TYPICAL CHARACTERISTICS - ADS6129
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
FFT for 20 MHz INPUT SIGNAL
FFT for 60 MHz INPUT SIGNAL
0
0
SFDR = 94.87 dBc
SINAD = 70.73 dBFS
SNR = 70.77 dBFS
THD = 89.9 dBc
−20
−40
Amplitude − dB
Amplitude − dB
−40
SFDR = 87.8 dBc
SINAD = 70.5 dBFS
SNR = 70.6 dBFS
THD = 84 dBc
−20
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
25
50
75
100
f − Frequency − MHz
125
0
25
50
G039
Figure 51.
FFT for 170 MHz INPUT SIGNAL
125
G040
FFT for 300 MHz INPUT SIGNAL
0
SFDR = 81.9 dBc
SINAD = 69.2 dBFS
SNR = 69.5 dBFS
THD = 79.7 dBc
−20
SFDR = 76.09 dBc
SINAD = 67.13 dBFS
SNR = 67.95 dBFS
THD = 73.72 dBc
−20
−40
Amplitude − dB
−40
Amplitude − dB
100
Figure 52.
0
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
25
50
75
100
f − Frequency − MHz
125
0
25
50
G041
G042
fIN1 = 185.1 MHz, –36 dBFS
fIN2 = 190.1 MHz, –36 dBFS
2-Tone IMD = –103 dBFS
SFDR = –97 dBFS
−20
−40
Amplitude − dB
−40
125
FFT for 2-TONE INPUT SIGNAL (IMD)
0
fIN1 = 185.1 MHz, –7 dBFS
fIN2 = 190.1 MHz, –7 dBFS
2-Tone IMD = –90.5 dBFS
SFDR = –91 dBFS
−20
100
Figure 54.
FFT for 2-TONE INPUT SIGNAL (IMD)
0
75
f − Frequency − MHz
Figure 53.
Amplitude − dB
75
f − Frequency − MHz
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
25
50
75
f − Frequency − MHz
100
125
G043
0
25
50
Figure 55.
Copyright © 2008, Texas Instruments Incorporated
75
100
f − Frequency − MHz
125
G044
Figure 56.
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37
ADS6149/ADS6129
ADS6148/ADS6128
SLWS211B – JULY 2008 – REVISED OCTOBER 2008 ..................................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS - ADS6129 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
SFDR
vs
INPUT FREQUENCY
SNR
vs
INPUT FREQUENCY
100
74
95
73
72
LVDS
85
SNR − dBFS
SFDR − dBc
90
80
CMOS
75
70
70
LVDS
69
68
65
67
60
66
55
65
50
CMOS
64
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
G045
Figure 57.
Figure 58.
SFDR
vs
GAIN
SINAD
vs
GAIN
100
5 dB
80
6 dB
75
70
2 dB
65
60
1 dB
2 dB
71
SINAD − dBFS
85
0 dB
73
3 dB
4 dB
90
69
67
65
3 dB
63
4 dB
5 dB
61
6 dB
59
1 dB
55
57
0 dB
50
Input adjusted to get −1dBFS input
55
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
G047
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
Figure 59.
38
G046
75
Input adjusted to get −1dBFS input
95
SFDR − dBc
71
Submit Documentation Feedback
G048
Figure 60.
Copyright © 2008, Texas Instruments Incorporated
Product Folder Link(s): ADS6149/ADS6129 ADS6148/ADS6128
ADS6149/ADS6129
ADS6148/ADS6128
www.ti.com ..................................................................................................................................................... SLWS211B – JULY 2008 – REVISED OCTOBER 2008
TYPICAL CHARACTERISTICS - ADS6129 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
PERFORMANCE
vs
INPUT AMPLITUDE
PERFORMANCE
vs
INPUT COMMON-MODE VOLTAGE
110
76
73
SNR (dBFS)
72
60
71
50
70
fIN = 60 MHz
−50
−40
−30
−20
−10
68
1.40
1.45
1.50
1.55
1.60
PERFORMANCE
vs
AVDD SUPPLY
PERFORMANCE
vs
DRVDD SUPPLY
90
94
74
92
73
88
72
86
71
84
SNR
82
3.2
3.3
3.4
3.5
AVDD − Supply Voltage − V
3.6
74
73
SFDR
88
72
86
71
84
69
82
80
1.6
G051
75
90
70
68
3.7
76
fIN = 60.1 MHz
AVDD = 3.3 V
70
SNR
69
1.7
1.8
1.9
68
2.0
DRVDD − Supply Voltage − V
Figure 63.
Copyright © 2008, Texas Instruments Incorporated
G050
96
75
SFDR
69
1.65
VCM − Common-Mode Voltage of Analog Inputs − V
76
3.1
70
Figure 62.
92
SFDR − dBc
82
1.35
G049
fIN = 60.1 MHz
DRVDD = 1.8 V
3.0
71
SNR
Figure 61.
96
80
2.9
86
84
0
Input Amplitude − dBFS
94
72
69
SFDR (dBc)
SFDR − dBc
30
−60
SFDR
88
SNR − dBFS
40
73
SNR − dBFS
80
90
SFDR − dBc
74
SNR − dBFS
90
70
74
75
SNR − dBFS
SFDR − dBc, dBFS
100
92
fIN = 60 MHz
SFDR (dBFS)
G052
Figure 64.
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39
ADS6149/ADS6129
ADS6148/ADS6128
SLWS211B – JULY 2008 – REVISED OCTOBER 2008 ..................................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS - ADS6129 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
PERFORMANCE
vs
TEMPERATURE
PERFORMANCE
vs
INPUT CLOCK AMPLITUDE
74
94
fIN = 60 MHz
92
73
75
86
71
SNR
84
70
74
SFDR
SFDR − dBc
72
SFDR
SNR − dBFS
SFDR − dBc
90
88
88
73
86
72
84
71
82
82
69
80
−40
0
20
40
60
78
0.20
80
T − Temperature − °C
1.70
2.20
Figure 66.
PERFORMANCE
vs
INPUT CLOCK DUTY CYCLE
PERFORMANCE
vs
VCM VOLTAGE
73
84
72
SNR
80
71
76
69
45
50
55
60
Input Clock Duty Cycle − %
65
73
SFDR
86
72
84
71
SNR
82
70
72
74
88
SFDR − dBc
88
G054
fIN = 60.1 MHz
External Reference Mode
74
SFDR
2.70
90
SNR − dBFS
92
SFDR − dBc
1.20
Input Clock Amplitude − VPP
75
40
68
0.70
G053
fIN = 5 MHz
35
69
Figure 65.
96
30
70
SNR
80
68
−20
SNR − dBFS
90
76
fIN = 60 MHz
80
1.30
70
SNR − dBFS
92
70
1.35
G055
1.40
1.45
1.50
1.55
VVCM − VCM Voltage − V
Figure 67.
1.60
1.65
69
1.70
G056
Figure 68.
OUTPUT NOISE HISTOGRAM
60
Occurence − %
50
40
30
20
10
0
2047 2048 2049 2050 2051 2052 2053 2054 2055 2056
Output Code
G057
Figure 69.
40
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ADS6149/ADS6129
ADS6148/ADS6128
www.ti.com ..................................................................................................................................................... SLWS211B – JULY 2008 – REVISED OCTOBER 2008
TYPICAL CHARACTERISTICS - ADS6128
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
FFT for 20 MHz INPUT SIGNAL
FFT for 60 MHz INPUT SIGNAL
0
0
SFDR = 90.8 dBc
SINAD = 70.6 dBFS
SNR = 70.7 dBFS
THD = 87.8 dBc
−20
−40
Amplitude − dB
Amplitude − dB
−40
SFDR = 92.5 dBc
SINAD = 70.5 dBFS
SNR = 70.6 dBFS
THD = 88.9 dBc
−20
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
20
40
60
80
100
f − Frequency − MHz
0
20
40
G058
Figure 70.
FFT for 170 MHz INPUT SIGNAL
100
G059
FFT for 300 MHz INPUT SIGNAL
0
SFDR = 82.59 dBc
SINAD = 69.18 dBFS
SNR = 69.42 dBFS
THD = 80.99 dBc
−20
SFDR = 76.3 dBc
SINAD = 67.5 dBFS
SNR = 68.1 dBFS
THD = 75.1 dBc
−20
−40
Amplitude − dB
−40
Amplitude − dB
80
Figure 71.
0
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
20
40
60
80
100
f − Frequency − MHz
0
20
40
60
80
100
f − Frequency − MHz
G060
Figure 72.
G061
Figure 73.
FFT for 2-TONE INPUT SIGNAL (IMD)
FFT for 2-TONE INPUT SIGNAL (IMD)
0
0
fIN1 = 185.1 MHz, –7 dBFS
fIN2 = 190.1 MHz, –7 dBFS
2-Tone IMD = –90 dBFS
SFDR = –88 dBFS
−20
fIN1 = 185.1 MHz, –36 dBFS
fIN2 = 190.1 MHz, –36 dBFS
2-Tone IMD = –101 dBFS
SFDR = –96 dBFS
−20
−40
Amplitude − dB
−40
Amplitude − dB
60
f − Frequency − MHz
−60
−80
−100
−60
−80
−100
−120
−120
−140
−140
−160
−160
0
20
40
60
f − Frequency − MHz
80
100
0
G062
20
40
Figure 74.
Copyright © 2008, Texas Instruments Incorporated
60
80
100
f − Frequency − MHz
G063
Figure 75.
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41
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ADS6148/ADS6128
SLWS211B – JULY 2008 – REVISED OCTOBER 2008 ..................................................................................................................................................... www.ti.com
TYPICAL CHARACTERISTICS - ADS6128 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
SFDR
vs
INPUT FREQUENCY
SNR
vs
INPUT FREQUENCY
100
74
95
73
72
LVDS
85
SNR − dBFS
SFDR − dBc
90
80
CMOS
75
70
70
LVDS
69
68
65
67
60
66
55
65
50
CMOS
64
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
G064
Figure 76.
Figure 77.
SFDR
vs
GAIN
SINAD
vs
GAIN
100
5 dB
80
6 dB
75
70
2 dB
65
60
1 dB
2 dB
71
SINAD − dBFS
85
0 dB
73
3 dB
4 dB
90
69
67
65
3 dB
63
4 dB
5 dB
61
6 dB
59
1 dB
55
57
0 dB
50
Input adjusted to get −1dBFS input
55
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
G066
0
50
100 150 200 250 300 350 400 450 500
fIN − Input Frequency − MHz
Figure 78.
42
G065
75
Input adjusted to get −1dBFS input
95
SFDR − dBc
71
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G067
Figure 79.
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TYPICAL CHARACTERISTICS - ADS6128 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
PERFORMANCE
vs
INPUT AMPLITUDE
PERFORMANCE
vs
INPUT COMMON-MODE VOLTAGE
110
76
60
71
50
70
SFDR (dBc)
−40
−30
−20
−10
68
1.45
1.50
1.55
1.60
PERFORMANCE
vs
AVDD SUPPLY
PERFORMANCE
vs
DRVDD SUPPLY
90
75
94
74
92
73
88
72
SNR
86
71
84
82
3.3
3.4
3.5
AVDD − Supply Voltage − V
3.6
G069
76
fIN = 60.1 MHz
AVDD = 3.3 V
75
74
SFDR
90
73
88
72
SNR
86
71
70
84
70
69
82
69
68
3.7
80
1.6
G070
1.7
1.8
1.9
68
2.0
DRVDD − Supply Voltage − V
Figure 82.
Copyright © 2008, Texas Instruments Incorporated
69
1.65
96
SFDR − dBc
SFDR
3.2
1.40
VCM − Common-Mode Voltage of Analog Inputs − V
76
3.1
70
Figure 81.
92
SFDR − dBc
86
1.35
G068
fIN = 60.1 MHz
DRVDD = 1.8 V
3.0
71
SNR
Figure 80.
96
80
2.9
90
88
0
Input Amplitude − dBFS
94
72
69
fIN = 60 MHz
−50
SFDR
92
SNR − dBFS
40
73
SNR − dBFS
72
SFDR − dBc
73
SNR (dBFS)
70
30
−60
94
74
SNR − dBFS
90
80
74
75
SNR − dBFS
SFDR − dBc, dBFS
100
96
fIN = 60 MHz
SFDR (dBFS)
G071
Figure 83.
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TYPICAL CHARACTERISTICS - ADS6128 (continued)
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
PERFORMANCE
vs
TEMPERATURE
PERFORMANCE
vs
INPUT CLOCK AMPLITUDE
96
SFDR
92
94
74
76
fIN = 60 MHz
75
88
72
SNR
86
71
84
70
82
−40
69
−20
0
20
40
60
90
88
86
71
84
70
82
69
1.70
2.20
Figure 85.
PERFORMANCE
vs
INPUT CLOCK DUTY CYCLE
PERFORMANCE
vs
VCM VOLTAGE
73
84
72
SNR
80
71
76
94
69
45
50
55
60
Input Clock Duty Cycle − %
65
73
SFDR
92
72
90
71
SNR
88
70
72
SFDR − dBc
SFDR
74
fIN = 60.1 MHz
External Reference Mode
74
88
G073
96
SNR − dBFS
92
SFDR − dBc
1.20
Input Clock Amplitude − VPP
75
40
68
0.70
G072
fIN = 5 MHz
35
72
SNR
Figure 84.
96
30
73
80
0.20
80
T − Temperature − °C
74
SFDR
SFDR − dBc
73
SNR − dBFS
SFDR − dBc
92
90
SNR − dBFS
75
fIN = 60.1 MHz
86
1.30
70
1.35
G074
1.40
1.45
70
1.50
1.55
VVCM − VCM Voltage − V
Figure 86.
SNR − dBFS
94
1.60
1.65
69
1.70
G075
Figure 87.
OUTPUT NOISE HISTOGRAM
60
Occurence − %
50
40
30
20
10
0
2048 2049 2050 2051 2052 2053 2054 2055 2056
Output Code
G076
Figure 88.
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TYPICAL CHARACTERISTICS - COMMON PLOTS
All plots are at 25°C, AVDD = 3.3 V, DRVDD = 1.8 V, maximum rated sampling frequency, sine wave input clock. 1.5 VPP
differential clock amplitude, 50% clock duty cycle, –1 DBFS differential analog input, internal reference mode, 0 dB gain,
LVDS output interface (unless otherwise noted)
CMRR
vs
INPUT FREQUENCY
TOTAL POWER
vs
SAMPLING FREQUENCY
1.0
0.9
−20
0.8
P − Total Power − W
0
−10
CMRR − dB
−30
−40
−50
−60
−70
CL = 10 pF
0.7
0.6
LVDS
0.5
0.4
CMOS
0.3
−80
0.2
−90
0.1
0.0
−100
0
20
40
60
80
0
100
fIN − Input Frequency − MHz
50
100
150
200
fS − Sampling Frequency − MSPS
G079
Figure 89.
250
G077
Figure 90.
DRVDD CURRENT
vs
SAMPLING FREQUENCY
IDRVDD − DRVDD Current − mA
100
fIN = 3 MHz
CL = 10 pF
90
80
70
LVDS
60
50
40
CMOS
30
20
OE Disabled
10
0
0
50
100
150
200
fS − Sampling Frequency − MSPS
250
G078
Figure 91.
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CONTOUR PLOTS - ADS6149/ADS6148/ADS6129/ADS6128
Plots are at 25°C, AVDD = 3.3V, DRVDD = 1.8 V, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty
cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, LVDS output interface (unless otherwise noted)
250
240
92
84
76
84
84
220
fS - Sampling Frequency - MSPS
80
88
64
68
72
60
84
200
76
84
68
80
180
88
160
76
72
84
80
84
140
68
80
120
50
60
72
88
92
80
20
64
88
88
100
64
60
92
76
84
100
200
150
250
350
300
400
500
450
fIN - Input Frequency - MHz
65
60
70
75
80
85
90
95
SFDR - dBc
M0049-17
Figure 92. SFDR Contour Plot (0 dB gain)
250
240
84
84
84
68
72
80
64
76
fS - Sampling Frequency - MSPS
220
72
200
180
60
88
84
80
88
68
84
160
84
76
84
64
72
84
60
140
120
84
100
80
20
64
80
88
84
100
200
300
400
500
60
68
72
76
600
800
700
fIN - Input Frequency - MHz
65
60
70
80
85
90
SFDR - dBc
95
M0049-18
Figure 93. SFDR Contour Plot (6 dB gain)
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CONTOUR PLOTS - ADS6149/ADS6148
Plots are at 25°C, AVDD = 3.3V, DRVDD = 1.8 V, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty
cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, LVDS output interface (unless otherwise noted)
250
240
220
fS - Sampling Frequency - MSPS
66
67
73
70
71
72
69
68
200
180
69
73
70
72
160
66
67
68
71
140
120
69
73
100
66
70
71
72
68
67
350
400
65
74
80
20
50
100
200
150
250
300
500
450
fIN - Input Frequency - MHz
64
66
65
67
68
69
70
71
72
73
74
75
SNR - dBFS
M0048-19
Figure 94. SNR Contour Plot (0 dB gain)
250
240
67
66
65
64
63
62
fS - Sampling Frequency - MSPS
220
200
67
180
160
66
68
63
64
65
62
140
120
68
63
64
65
66
67
62
100
61
80
20
100
300
200
400
500
600
700
800
fIN - Input Frequency - MHz
60
61
63
62
64
65
66
67
SNR - dBFS
68
69
M0048-20
Figure 95. SNR Contour Plot (6 dB gain)
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APPLICATION INFORMATION
THEORY OF OPERATION
ADS6149/48 and ADS6129/28 is a family of high performance, low power 14-bit and 12-bit pipeline A/D
converters with maximum sampling rate up to 250 MSPS.
At every rising edge of the input clock, the analog input signal is sampled and sequentially converted by a
pipeline of low resolution stages. In each stage, the sampled and held signal is converted by a high speed, low
resolution flash sub-ADC. The difference (residue) between the stage input and its quantized equivalent is
gained and propagates to the next stage. At every clock, each succeeding stage resolves the sampled input with
greater accuracy. The digital outputs from all stages are combined in a digital correction logic block to create the
final 14 or 12 bit code, after a data latency of 18 clock cycles.
The digital output is available as either DDR LVDS or parallel CMOS and coded in either straight offset binary or
binary 2s complement format.
The dynamic offset of the first stage sub-ADC limits the maximum analog input frequency to about 500MHz (with
2VPP amplitude) and about 800MHz (with 1VPP amplitude).
ANALOG INPUT
The analog input consists of a switched-capacitor based differential sample and hold architecture.
This differential topology results in a good AC performance even for high input frequencies at high sampling
rates. The INP and INM pins have to be externally biased around a common-mode voltage of 1.5V, available on
VCM pin. For a full-scale differential input, each input pin INP, INM has to swing symmetrically between VCM +
0.5V and VCM – 0.5V, resulting in a 2Vpp differential input swing.
Sampling
Switch
Lpkg~1 nH
10 W
Sampling
Capacitor
RCR Filter
INP
Cbond
~ 1 pF
100 W
Resr
200 W
Ron
15 W
Csamp
2 pF
3 pF
3 pF
Lpkg~1 nH
Cpar2
0.5 pF
10 W
Ron
10 W
Cpar1
0.25 pF
100 W
Csamp
2 pF
Ron
15 W
INM
Cpar2
0.5 pF
Cbond
~ 1 pF
Resr
200 W
Sampling
Capacitor
Sampling
Switch
Figure 96. Analog Input Equivalent Circuit
The input sampling circuit has a high 3-dB bandwidth that extends up to 700 MHz (measured from the input pins
to the sampled voltage).
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Drive Circuit Requirements
For optimum performance, the analog inputs must be driven differentially. This improves the common-mode
noise immunity and even order harmonic rejection. A 5 Ω to 15 Ω resistor in series with each input pin is
recommended to damp out ringing caused by package parasitics. It is also necessary to present low impedance
(< 50 Ω) for the common mode switching currents. This can be achieved by using two resistors from each input
terminated to the common mode voltage (VCM).
Note that the device includes an internal R-C filter from each input to ground. The purpose of this filter is to
absorb the glitches caused by the opening and closing of the sampling capacitors. The cut-off frequency of the
R-C filter involves a trade-off. A lower cut-off frequency (larger C) absorbs glitches better, but also reduces the
input bandwidth and the maximum input frequency that can be supported. On the other hand, with no internal
R-C filter, high input frequency can be supported, but now the sampling glitches need to be supplied by the
external driving circuit. This has limitations due to the presence of the package bond-wire inductance.
In ADS61x9/x8, the R-C component values have been optimized while supporting high input bandwidth (up to
750 MHz). However, in applications where high input frequency support is not required, the filtering of the
glitches can be improved further using an external R-C-R filter (as shown in Figure 99 and Figure 100).
In addition to the above, the drive circuit may have to be designed to provide a low insertion loss over the
desired frequency range and matched impedance to the source. While doing this, the ADC input impedance
must be considered. Figure 97 and Figure 98 show the impedance (Zin = Rin || Cin) looking into the ADC input
pins.
100
Resistance - kW
10
1
0.1
0.01
0
100
200
300
400
500
600
700
800
900
1000
f - Frequency - MHz
Figure 97. ADC Analog Input Resistance (Rin) Across Frequency
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4.5
4
Capacitance - pF
3.5
3
2.5
2
1.5
1
0
100
200
300
400
500
600
700
800
900
1000
f - Frequency - MHz
Figure 98. ADC Analog Input Capacitance (Cin) Across Frequency
Driving Circuit
Two example driving circuit configurations are shown in Figure 99 and Figure 100 – one optimized for low
bandwidth (low input frequencies) and the other one for high bandwidth to support higher input frequencies.
In Figure 99, an external R-C-R filter using 22pF has been used. Together with the series inductor (39nH), this
combination forms a filter and absorbs the sampling glitches. Due to the large capacitor (22pF) in the R-C-R and
the 15Ω resistors in series with each input pin, the drive circuit has low bandwidth, and supports low input
frequencies (< 100MHz)..
To support high input frequencies (up to about 300MHz, see Figure 100), the capacitance used in the R-C-R is
reduced to 3.3pF and the series inductors are shorted out. Together with the lower series resistors (5Ω), this
drive circuit provides high bandwidth and supports high input frequencies.
A transformer such as ADT1-1WT or ETC1-1-13 can be used up to 300MHz.
In Figure 100, by dropping the external R-C-R filter, the drive circuit has high bandwidth and can support high
input frequencies (> 300MHz). For example, a transformer such as the ADTL2-18 can be used.
Note that both the drive circuits have been terminated by 50Ω near the ADC side. The termination is
accomplished using a 25Ω resistor from each input to the 1.5V common-mode (VCM) from the device. This
biases the analog inputs around the required common-mode voltage.
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39 nH
15 W
0.1 mF
0.1 mF
INP
50 W
0.1 mF
50 W
25 W
22 pF
25 W
50 W
50 W
INM
1:1
1:1
0.1 mF
15 W
39 nH
VCM
Figure 99. Drive Circuit with Low Bandwidth (for low input frequencies)
The mismatch in the transformer parasitic capacitance (between the windings) results in degraded even-order
harmonic performance. Connecting two identical RF transformers back to back helps minimize this mismatch and
good performance is obtained for high frequency input signals. An additional termination resistor pair may be
required between the two transformers as shown in the figures. The center point of this termination is connected
to ground to improve the balance between the P and M sides. The values of the terminations between the
transformers and on the secondary side have to be chosen to get an effective 50Ω (in the case of 50Ω source
impedance).
0.1 mF
5W
0.1 mF
INP
0.1 mF
50 W
25 W
3.3 pF
25 W
5W
50 W
INM
1:1
1:1
0.1 mF
VCM
Figure 100. Drive Circuit with High Bandwidth (for high input frequencies)
Input Common-Mode
To ensure a low-noise common-mode reference, the VCM pin is filtered with a 0.1µF low-inductance capacitor
connected to ground. The VCM pin is designed to directly drive the ADC inputs. The input stage of the ADC
sinks a common-mode current in the order of 500µA (per input pin, at 250 MSPS). Equation 1 describes the
dependency of the common-mode current and the sampling frequency.
500 mA ´ Fs
250 MSPS
(1)
This equation helps to design the output capability and impedance of the CM driving circuit accordingly.
REFERENCE
ADS614X/2X has built-in internal references REFP and REFM, requiring no external components. Design
schemes are used to linearize the converter load seen by the references; this and the on-chip integration of the
requisite reference capacitors eliminates the need for external decoupling. The full-scale input range of the
converter can be controlled in the external reference mode as explained below. The internal or external reference
modes can be selected by programming the serial interface register bit <REF>.
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INTREF
Internal
Reference
VCM
INTREF
EXTREF
REFM
REFP
S0165-09
Figure 101. Reference Section
Internal Reference
When the device is in internal reference mode, the REFP and REFM voltages are generated internally.
Common-mode voltage (1.5V nominal) is output on VCM pin, which can be used to externally bias the analog
input pins.
External Reference
When the device is in external reference mode, the VCM acts as a reference input pin. The voltage forced on the
VCM pin is buffered and gained by 1.33 internally, generating the REFP and REFM voltages. The differential
input voltage corresponding to full-scale is given by Equation 2.
Full-scale differential input pp = (Voltage forced on VCM) × 1.33
(2)
In this mode, the 1.5V common-mode voltage to bias the input pins has to be generated externally.
CLOCK INPUT
ADS614X/2X clock inputs can be driven differentially (sine, LVPECL or LVDS) or single-ended (LVCMOS), with
little or no difference in performance between them. The common-mode voltage of the clock inputs is set to VCM
using internal 5-kΩ resistors. This allows using transformer-coupled drive circuits for sine wave clock or
ac-coupling for LVPECL, LVDS clock sources.
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Clock buffer
Lpkg
~1 nH
20 W
CLKP
Cbond
~1 pF
Ceq
Ceq
5 kW
Resr
~100 W
VCM
2 pF
5 kW
Lpkg
~1 nH
20 W
CLKM
Cbond
~1 pF
Resr
~100 W
Ceq ~ 1 to 3 pF, equivalent input capacitance of clock buffer
Figure 102. Internal Clock Buffer
Single-ended CMOS clock can be ac-coupled to the CLKP input, with CLKM connected to ground with a 0.1-µF
capacitor, as shown in Figure 104. For best performance, the clock inputs have to be driven differentially,
reducing susceptibility to common-mode noise. For high input frequency sampling, it is recommended to use a
clock source with low jitter. Band-pass filtering of the clock source can help reduce the effect of jitter. There is no
change in performance with a non-50% duty cycle clock input.
0.1 mF
0.1 mF
CMOS Clock Input
CLKP
CLKP
Differential Sine-Wave
or PECL or LVDS Clock Input
VCM
0.1 mF
0.1 mF
CLKM
CLKM
S0168-14
S0167-10
Figure 103. Differential Clock Driving Circuit
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Figure 104. Single-Ended Clock Driving Circuit
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FINE GAIN CONTROL
ADS614X/2X includes gain settings that can be used to get improved SFDR performance (compared to no gain).
The gain is programmable from 0dB to 6dB (in 0.5 dB steps). For each gain setting, the analog input full-scale
range scales proportionally, as shown in Table 9.
The SFDR improvement is achieved at the expense of SNR; for each gain setting, the SNR degrades about
0.5–1dB. The SNR degradation is less at high input frequencies. As a result, the gain is useful at high input
frequencies as the SFDR improvement is significant with marginal degradation in SNR.
So, the gain can be used to trade-off between SFDR and SNR. Note that the default gain after reset is 0 dB.
Table 9. Full-Scale Range Across Gains
Gain, dB
Type
0
Default after reset
Full-Scale, VPP
2V
1
1.78
2
1.59
3
4
Fine, programmable
1.42
1.26
5
1.12
6
1.00
OFFSET CORRECTION
ADS61x9/x8 has an internal offset correction algorithm that estimates and corrects the dc offset up to ±10mV.
The correction can be enabled using the serial register bit <ENABLE OFFSET CORR>. Once enabled, the
algorithm estimates the channel offset and applies the correction every clock cycle. The time constant of the
correction loop is a function of the sampling clock frequency. The time constant can be controlled using register
bits <OFFSET CORR TIME CONSTANT> as described inTable 10.
After the offset is estimated, the correction can be locked in by setting <OFFSET CORR TIME CONSTANT> = 0.
Once locked, the last estimated value is used for offset correction every clock cycle. Note that offset correction is
disabled by default after reset.
Figure 105 shows the time response of the offset correction algorithm, after it is enabled.
Table 10. Time Constant of Offset Correction Algorithm
<OFFSET CORR TIME CONSTANT> D3-D0
Time constant (TCCLK), number of clock
cycles
Time constant, sec (=TCCLK x 1/Fs) (1)
0000
256 k
1 ms
0001
512 k
2 ms
0010
1M
4 ms
0011
2M
8 ms
0100
4M
17 ms
0101
8M
33 ms
0110
16 M
67 ms
0111
32 M
134 ms
1000
64 M
268 ms
1001
128 M
536 ms
1010
256 M
1.1 s
1011
512 M
2.2 s
1100
RESERVED
–
1101
RESERVED
–
1110
RESERVED
–
1111
RESERVED
–
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8204
Offset Correction Disabled
8200
Offset Correction Enabled
8196
8192
8188
Code − LSB
8184
Output Data With
Offset Corrected
8180
8176
8172
8168
Output Data With
36 LSB Offset
8164
8160
8156
8152
8148
0
4
8
12
16
20
24
28
32
36
40
44
48
52
t − Time − µs
56
G080
Figure 105. Output Code Time Response With Offset Correction Enabled
POWER DOWN
ADS614X/2X has three power down modes – power down global, standby and output buffer disable.
Power Down Global
In this mode, the entire chip including the A/D converter, internal reference and the output buffers are powered
down resulting in reduced total power dissipation of about 20 mW. The output buffers are in high impedance
state. The wake-up time from global power down to data becoming valid in normal mode is typically 25 µs.
This can be controlled using register bit <PDN GLOBAL> or using SDATA pin (in parallel configuration mode).
Standby
Here, only the A/D converter is powered down and internal references are active, resulting in fast wake-up time
of 300 ns. The total power dissipation in standby is about 120 mW.
This can be controlled using register bit <STANDBY>.
Output Buffer Disable
The output buffers can be disabled and put in high impedance state – wakeup time from this mode is fast, about
40 ns. This can be controlled using register bit <PDN OBUF>.
Input Clock Stop
In addition to the above, the converter enters a low-power mode when the input clock frequency falls below 1
MSPS. The power dissipation is about 120 mW.
POWER SUPPLY SEQUENCE
During power-up, the AVDD and DRVDD supplies can come up in any sequence. The two supplies are
separated in the device. Externally, they can be driven from separate supplies or from a single supply.
DIGITAL OUTPUT INFORMATION
ADS614X/2X provides 14-bit/12-bit data and an output clock synchronized with the data.
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Output Interface
Two output interface options are available – Double Data Rate (DDR) LVDS and parallel CMOS. They can be
selected using the serial interface register bit <ODI> or using DFS pin in parallel configuration mode.
DDR LVDS Outputs
In this mode, the data bits and clock are output using LVDS (Low Voltage Differential Signal) levels. Two data
bits are multiplexed and output on each LVDS differential pair.
Pins
14 bit ADC data
CLKOUTP
CLKOUTM
Output Clock
D0_D1_P
D0_D1_M
Data bits D0, D1
D2_D3_P
D2_D3_M
Data bits D2, D3
D4_D5_P
D4_D5_M
Data bits D4, D5
CLKOUTP
CLKOUTM
D0_D1_P
D0_D1_M
LVDS Buffers
LVDS Buffers
Pins
Output Clock
Data bits D0, D1
P
D2_D3_
D2_D3_M
D4_D5_P
D4_D5_M
Data bits D2, D3
Data bits D4, D5
12 bit ADC data
D6_D7_P
D6_D7_P
D6_D7_M
Data bits D6, D7
D8_D9_P
D8_D9_M
Data bits D8, D9
D10_D11_P
D10_D11_M
Data bits D10, D11
D12_D13_P
D12_D13_M
Data bits D12, D13
D6_D7_M
D8_D9_P
D8_D9_M
Data bits D6, D7
Data bits D8, D9
D10_D11_P
D10_D11_M
Data bits D10, D11
ADS612X
ADS 614 X
Figure 106. 14-Bit ADC LVDS Outputs
Figure 107. 12-Bit ADC LVDS Outputs
Even data bits D0, D2, D4… are output at the falling edge of CLKOUTP and the odd data bits D1, D3, D5… are
output at the rising edge of CLKOUTP. Both the rising and falling edges of CLKOUTP have to be used to capture
all of the data bits (see Figure 108).
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CLKOUTP
CLKOUTM
D0_D1_P,
D0_D1_M
D0
D1
D0
D1
D2_D3_P,
D2_D3_M
D2
D3
D2
D3
D4_D5_P,
D4_D5_M
D4
D5
D4
D5
D6_D7_P,
D6_D7_M
D6
D7
D6
D7
D8_D9_P,
D8_D9_M
D8
D9
D8
D9
D10_D11_P,
D10_D11_M
D10
D11
D10
D11
D12_D13_P,
D12_D13_M
D12
D13
D12
D13
Sample N
Sample N+1
T0110-01
Figure 108. DDR LVDS Interface
LVDS Buffer
The equivalent circuit of each LVDS output buffer is shown in Figure 109. The buffer is designed to present an
output impedance of 100 Ω (Rout). The differential outputs can be terminated at the receive end by a 100 Ω
termination. The buffer output impedance behaves like a source-side series termination. By absorbing reflections
from the receiver end, it helps to improve signal integrity. Note that this internal termination cannot be disabled
and its value cannot be changed.
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+
–
Low
0.35 V
High
ADS6149/48/29/28
OUTP
+
–
–0.35 V
+
–
Rout
High
1.2 V
Low
External
100-W Load
OUTM
Switch impedance is
nominally 50 W (±10%)
When the High switches are closed, OUTP = 1.375 V, OUTM = 1.025 V
When the Low switches are closed, OUTP = 1.025 V, OUTM = 1.375 V
When the High (or Low) switches are closed, Rout = 100 W
S0374-01
Figure 109. LVDS Buffer Equivalent Circuit
Parallel CMOS Interface
In the CMOS mode, each data bit is output on separate pin as CMOS voltage level, every clock cycle. The rising
edge of the output clock CLKOUT can be used to latch data in the receiver (for sampling frequencies up to
150 MSPS).
Up to 150 MSPS, the setup and hold timings of the output data with respect to CLKOUT are specified. It is
recommended to minimize the load capacitance seen by data and clock output pins by using short traces to the
receiver. Also, match the output data and clock traces to minimize the skew between them.
For sampling frequencies > 150 MSPS, it is recommended to use an external clock to capture data. The delay
from input clock to output data and the data valid times are specified for the higher sampling frequencies. These
timings can be used to delay the input clock appropriately and use it to capture the data (see Figure 4).
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Pins
OVR_SDOUT
CLKOUT
D0
14-Bit ADC Data
CMOS
Output Buffers
D1
D2
•
•
•
D11
D12
D13
ADS614x
Figure 110. CMOS Output Interface
Output Buffer Strength Programmability
Switching noise (caused by CMOS output data transitions) can couple into the analog inputs during the instant of
sampling and degrade the SNR. The coupling and SNR degradation increases as the output buffer drive is made
stronger. To minimize this, the CMOS output buffers are designed with controlled drive strength to get best SNR.
The default drive strength also ensures wide data stable window for load capacitances up to 5 pF.
CMOS Interface Power Dissipation
With CMOS outputs, the DRVDD current scales with the sampling frequency and the load capacitance on every
output pin. The maximum DRVDD current occurs when each output bit toggles between 0 and 1 every clock
cycle. In an actual application, the DRVDD current would be determined by the average number of output bits
switching, which is a function of the sampling frequency and the nature of the analog input signal.
Digital current due to CMOS output switching = CL × DRVDD × (N × FAVG),
where
CL = load capacitance,
N x FAVG = average number of output bits switching.
Figure 91 shows the current across sampling frequencies at 2 MHz analog input frequency.
Output Data Format
Two output data formats are supported – 2s complement and offset binary. They can be selected using the serial
interface register bit <DATA FORMAT> or controlling the DFS pin in parallel configuration mode.
In the event of an input voltage overdrive, the digital outputs go to the appropriate full scale level. For a positive
overdrive, the output code is 0x3FFF in offset binary output format, and 0x1FFF in 2s complement output format.
For a negative input overdrive, the output code is 0x0000 in offset binary output format and 0x2000 in 2s
complement output format.
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BOARD DESIGN CONSIDERATIONS
Grounding
A single ground plane is sufficient to give good performance, provided the analog, digital, and clock sections of
the board are cleanly partitioned. See the EVM User Guide (SLWU061) for details on layout and grounding.
Supply Decoupling
As the ADS61x9/x8 already includes internal decoupling, minimal external decoupling can be used without loss
in performance. Note that decoupling capacitors can help filter external power supply noise, so the optimum
number of capacitors would depend on the actual application. The decoupling capacitors should be placed close
to the converter supply pins.
Exposed Pad
In addition to providing a path for heat dissipation, the pad is also electrically connected to digital ground
internally. So, it is necessary to solder the exposed pad to the ground plane for best thermal and electrical
performance.
For detailed information, see the application notes for QFN Layout Guidelines (SLOA122) and QFN/SON PCB
Attachment (SLUA271).
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DEFINITION OF SPECIFICATIONS
Analog Bandwidth – The analog input frequency at which the power of the fundamental is reduced by 3 dB with
respect to the low frequency value.
Aperture Delay – The delay in time between the rising edge of the input sampling clock and the actual time at
which the sampling occurs. This delay will be different across channels. The maximum variation is specified as
aperture delay variation (channel-channel).
Aperture Uncertainty (Jitter) – The sample-to-sample variation in aperture delay.
Clock Pulse Width/Duty Cycle – The duty cycle of a clock signal is the ratio of the time the clock signal remains
at a logic high (clock pulse width) to the period of the clock signal. Duty cycle is typically expressed as a
percentage. A perfect differential sine-wave clock results in a 50% duty cycle.
Maximum Conversion Rate – The maximum sampling rate at which certified operation is given. All parametric
testing is performed at this sampling rate unless otherwise noted.
Minimum Conversion Rate – The minimum sampling rate at which the ADC functions.
Differential Nonlinearity (DNL) – An ideal ADC exhibits code transitions at analog input values spaced exactly
1 LSB apart. The DNL is the deviation of any single step from this ideal value, measured in units of LSBs.
Integral Nonlinearity (INL) – The INL is the deviation of the ADC's transfer function from a best fit line
determined by a least squares curve fit of that transfer function, measured in units of LSBs.
Gain Error – Gain error is the deviation of the ADC's actual input full-scale range from its ideal value. The gain
error is given as a percentage of the ideal input full-scale range. Gain error has two components: error due to
reference inaccuracy and error due to the channel. Both these errors are specified independently as EGREF and
EGCHAN.
To a first order approximation, the total gain error will be ETOTAL ~ EGREF + EGCHAN.
For example, if ETOTAL = ±0.5%, the full-scale input varies from (1-0.5/100) x FSideal to (1 + 0.5/100) x FSideal.
Offset Error – The offset error is the difference, given in number of LSBs, between the ADC's actual average
idle channel output code and the ideal average idle channel output code. This quantity is often mapped into mV.
Temperature Drift – The temperature drift coefficient (with respect to gain error and offset error) specifies the
change per degree Celsius of the parameter from TMIN to TMAX. It is calculated by dividing the maximum deviation
of the parameter across the TMIN to TMAX range by the difference TMAX–TMIN.
Signal-to-Noise Ratio – SNR is the ratio of the power of the fundamental (PS) to the noise floor power (PN),
excluding the power at DC and the first nine harmonics.
P
SNR = 10Log10 S
PN
(3)
SNR is either given in units of dBc (dB to carrier) when the absolute power of the fundamental is used as the
reference, or dBFS (dB to full scale) when the power of the fundamental is extrapolated to the converter’s
full-scale range.
Signal-to-Noise and Distortion (SINAD) – SINAD is the ratio of the power of the fundamental (PS) to the power
of all the other spectral components including noise (PN) and distortion (PD), but excluding dc.
PS
SINAD = 10Log10
PN + PD
(4)
SINAD is either given in units of dBc (dB to carrier) when the absolute power of the fundamental is used as the
reference, or dBFS (dB to full scale) when the power of the fundamental is extrapolated to the converter's
full-scale range.
Effective Number of Bits (ENOB) – The ENOB is a measure of the converter performance as compared to the
theoretical limit based on quantization noise.
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ENOB =
SINAD - 1.76
6.02
(5)
Total Harmonic Distortion (THD) – THD is the ratio of the power of the fundamental (PS) to the power of the
first nine harmonics (PD).
P
THD = 10Log10 S
PN
(6)
THD is typically given in units of dBc (dB to carrier).
Spurious-Free Dynamic Range (SFDR) – The ratio of the power of the fundamental to the highest other
spectral component (either spur or harmonic). SFDR is typically given in units of dBc (dB to carrier).
Two-Tone Intermodulation Distortion – IMD3 is the ratio of the power of the fundamental (at frequencies f1
and f2) to the power of the worst spectral component at either frequency 2f1–f2 or 2f2–f1. IMD3 is either given in
units of dBc (dB to carrier) when the absolute power of the fundamental is used as the reference, or dBFS (dB to
full scale) when the power of the fundamental is extrapolated to the converter’s full-scale range.
DC Power Supply Rejection Ratio (DC PSRR) – The DC PSSR is the ratio of the change in offset error to a
change in analog supply voltage. The DC PSRR is typically given in units of mV/V.
AC Power Supply Rejection Ratio (AC PSRR) – AC PSRR is the measure of rejection of variations in the
supply voltage by the ADC. If ΔVSUP is the change in supply voltage and ΔVout is the resultant change of the
ADC output code (referred to the input), then
DVOUT
(Expressed in dBc)
PSRR = 20Log 10
DVSUP
(7)
Voltage Overload Recovery – The number of clock cycles taken to recover to less than 1% error after an
overload on the analog inputs. This is tested by separately applying a sine wave signal with 6dB positive and
negative overload. The deviation of the first few samples after the overload (from their expected values) is noted.
Common Mode Rejection Ratio (CMRR) – CMRR is the measure of rejection of variation in the analog input
common-mode by the ADC. If ΔVcm_in is the change in the common-mode voltage of the input pins and ΔVOUT
is the resultant change of the ADC output code (referred to the input), then
DVOUT
(Expressed in dBc)
CMRR = 20Log10
DVCM
(8)
Cross-Talk (only for multi-channel ADC)– This is a measure of the internal coupling of a signal from adjacent
channel into the channel of interest. It is specified separately for coupling from the immediate neighboring
channel (near-channel) and for coupling from channel across the package (far-channel). It is usually measured
by applying a full-scale signal in the adjacent channel. Cross-talk is the ratio of the power of the coupling signal
(as measured at the output of the channel of interest) to the power of the signal applied at the adjacent channel
input. It is typically expressed in dBc.
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PACKAGE OPTION ADDENDUM
www.ti.com
17-Oct-2008
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
ADS6128IRGZR
ACTIVE
QFN
RGZ
48
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS6129IRGZR
ACTIVE
QFN
RGZ
48
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS6129IRGZT
ACTIVE
QFN
RGZ
48
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS6148IRGZR
ACTIVE
QFN
RGZ
48
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS6148IRGZT
ACTIVE
QFN
RGZ
48
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS6149IRGZR
ACTIVE
QFN
RGZ
48
2500 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS6149IRGZT
ACTIVE
QFN
RGZ
48
250
CU NIPDAU
Level-3-260C-168 HR
Green (RoHS &
no Sb/Br)
Lead/Ball Finish
MSL Peak Temp (3)
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
30-Sep-2008
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
Diameter Width
(mm) W1 (mm)
A0 (mm)
B0 (mm)
K0 (mm)
P1
(mm)
W
Pin1
(mm) Quadrant
ADS6129IRGZR
QFN
RGZ
48
2500
330.0
16.4
7.3
7.3
1.5
12.0
16.0
Q2
ADS6129IRGZT
QFN
RGZ
48
250
330.0
16.4
7.3
7.3
1.5
12.0
16.0
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
30-Sep-2008
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
ADS6129IRGZR
QFN
RGZ
48
2500
333.2
345.9
28.6
ADS6129IRGZT
QFN
RGZ
48
250
333.2
345.9
28.6
Pack Materials-Page 2
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