LINER LTM2220V-AA

LTM2220-AA
12-Bit, 170Msps ADC
FEATURES
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DESCRIPTION
Pin Compatible with the AD9430
Sample Rate: 170Msps
66.2dB SNR, 84dB SFDR
No Missing Codes
Single 3.3V supply
Power Dissipation: 1050mW
LVDS Digital Outputs
1.536VPP Input Range
Clock Duty Cycle Stabilizer
Out-of-Range Indicator
Data Ready Output Clock
Integrated Bypass Capacitors
100-Pin SiPLGA Package
The LTM®2220-AA is a 170Msps sampling 12-bit A/D
converter designed for digitizing high frequency, wide
dynamic range signals. The LTM2220-AA is perfect for
demanding communications applications with AC performance that includes 66.2dB SNR and 84dB spurious
free dynamic range.
DC specs include ±0.5LSB INL (typ), ±0.3LSB DNL (typ)
and no missing codes over temperature.
The CLK+ and CLK- inputs may be driven differentially or
single ended with a sine wave, PECL, TTL or CMOS inputs.
A clock duty cycle stabilizer allows high performance at
full speed for a wide range of clock duty cycles.
APPLICATIONS
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Wireless and Wired Broadband Communication
Spectral Analysis
The LTM2220-AA is pin compatible with the AD9430 when
used with LVDS outputs, 2’s complement output format
and the 1.536VPP input range.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
3.3V
AVDD
3.3V
REFERENCE
DRVDD
+
ANALOG
INPUT
INPUT
S/H
–
12-BIT
PIPELINED
ADC CORE
CORRECTION
LOGIC
D11
•
•
•
D0
OUTPUT
DRIVERS
LVDS
OUTPUTS
DRGND
CLOCK/DUTY
CYCLE
CONTROL
AGND
2220 TA01
CLOCK
INPUT
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LTM2220-AA
ABSOLUTE MAXIMUM RATINGS
AVDD = DRVDD (Notes 1, 2)
Supply Voltage (AVDD, DRVDD) .................................4V
Analog Input Voltage (Note 3) .... -0.3V to (AVDD + 0.3V)
Digital Input Voltage................... -0.3V to (AVDD + 0.3V)
Digital Output Voltage ............. -0.3V to (DRVDD + 0.3V)
Power Dissipation ............................................ 1500mW
Operating Temperature Range ..................-40°C to 85°C
Storage Temperature Range....................-65°C to 125°C
PACKAGE/ORDER INFORMATION
D9–
D9+
D10–
D10+
D11–
D11+
DRGND
DRVDD
OR–
OR+
AGND
AGND
AVDD
AVDD
AVDD
AGND
AGND
AGND
AVDD
AVDD
AGND
AGND
AVDD
AVDD
AGND
TOP VIEW
100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76
NC
1
75 DRVDD
NC
2
74 DRGND
NC
3
73 D8+
AGND
4
72 D8–
NC
5
71 D7+
NC
6
70 D7–
NC
7
69 D6+
AVDD
8
68 D6–
AGND
9
AGND
NC 10
67 DRGND
AGND
66 D5+
65 D5–
NC 11
AGND 12
64 DCO+
AGND 13
63 DCO–
AVDD 14
62 DRVDD
AVDD 15
61 DRGND
AGND 16
60 D4+
AGND
AGND
AGND 17
59 D4–
AVDD 18
58 D3+
AVDD 19
57 D3–
AGND 20
56 D2+
VIN+ 21
55 D2–
VIN– 22
54 DRVDD
AGND 23
53 DRGND
AVDD 24
52 D1+
AGND 25
51 D1–
D0+
D0–
DRGND
DRVDD
NC
NC
NC
NC
NC
AGND
AVDD
AVDD
AGND
CLK–
CLK+
AGND
AVDD
NC
AGND
AGND
AGND
AVDD
AVDD
AVDD
AGND
26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
SiPLGA PACKAGE
100-LEAD (16mm × 16mm)
TJMAX = 125°C, θJA = 20°C/W
EXPOSED PADS ARE AGND
ORDER PART NUMBER
LTM2220IV-AA#PBF
LGA PART MARKING
LTM2220V-AA
Consult LTC Marketing for parts specified with wider operating temperature ranges.
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LTM2220-AA
CONVERTER CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Note 4)
PARAMETER
CONDITIONS
Resolution (No Missing Codes)
Integral Linearity Error
(Note 5)
Differential Linearity Error
Offset Error
MIN
TYP
MAX
UNITS
●
12
●
–1.5
±0.5
1.5
LSB
●
–1
±0.3
1
LSB
–35
±3
35
mV
(Note 6)
Gain Error
Bits
±0.5
%FS
ANALOG INPUTS The ● denotes the specifications which apply over the full operating temperature range, otherwise
specifications are at TA = 25°C. (Note 4)
SYMBOL
PARAMETER
CONDITIONS
VIN
Differential Input Range
VIN, CM
Common Mode Input Range
VIN+ – VIN–
(VIN+ + VIN–)/2
fL
Lower –3dB Frequency
fH
Upper –3dB Frequency
tJITTER
Sample and Hold Jitter
MIN
●
●
TYP
MAX
1.536
0
RS = 75Ω
UNITS
V
3.6
V
1.6
kHz
195
MHz
0.2
psRMS
DYNAMIC ACCURACY The ● denotes the specifications which apply over the full operating temperature range,
otherwise specifications are at TA = 25°C. AIN = –1dBFS. (Note 4)
SYMBOL
PARAMETER
CONDITIONS
SNR
Signal-to-Noise Ratio
10MHz Input
SINAD
Signal to Noise Plus Distortion Ratio
70MHz Input
SFDR
IMD
●
63.5
10MHz Input
70MHz Input
SFDR
MIN
Spurious Free Dynamic Range: 2nd or
3rd Harmonic
10MHz Input
Spurious Free Dynamic Range: 4th
Harmonic or Higher
10MHz Input
Intermodulation Distortion
fIN1 = 138MHz, fIN2 = 140MHz
70MHz Input
70MHz Input
●
63.2
TYP
MAX
UNITS
66.2
dB
66.1
dB
66.1
dB
65.9
dB
84
dB
dB
●
70
84
90
dB
●
78
90
dB
81
dB
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LTM2220-AA
DIGITAL INPUTS AND OUTPUTS The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Note 4)
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
CLOCK INPUTS (CLK+, CLK–)
VID
Differential Input Voltage
VICM
Common Mode Input Voltage
RIN
Input Resistance
CIN
Input Capacitance
Internally Set
Externally Set
●
0.2
●
1.1
(Note 7)
V
1.6
1.6
V
V
2.5
6
kΩ
3
pF
DIGITAL LOGIC OUTPUTS
VOD
Differential Output Voltage
VOS
Output Common Mode Voltage
100Ω Load
●
247
350
454
●
1.125
1.250
1.375
mV
V
POWER REQUIREMENTS
The ● denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at TA = 25°C. (Note 4)
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
AVDD
Analog Supply Voltage
(Note 8)
●
3.1
3.3
3.5
UNITS
V
DRVDD
Digital Supply Voltage
(Note 8)
●
3.0
3.3
3.6
V
IAVDD
Analog Supply Current
●
264
288
mA
IDVDD
Digital Supply Current
●
55
70
mA
PDISS
Power Dissipation
●
1050
1182
mW
TIMING CHARACTERISTICS
The ● denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at TA = 25°C. (Note 4)
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
fS
Sampling Frequency
170
MHz
tL
CLK Low Time
tH
CLK High Time
tAP
Sample-and-Hold Aperture Delay
tD
CLK to DATA Delay
(Note 7)
●
1.5
3
4.3
ns
tC
CLK to DCO Delay
(Note 7)
●
1.5
3
4.3
ns
DATA to DCO Skew
(tC – tD), (Note 7)
●
–0.6
0
0.6
ns
●
1
(Note 7)
●
2
2.94
500
ns
(Note 7)
●
2
2.94
500
ns
0
ns
Rise Time
0.5
ns
Fall Time
0.5
ns
Pipeline Latency
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: All voltage values are with respect to ground with AGND and
DRGND wired together (unless otherwise noted).
Note 3: When these pin voltages are taken below GND or above VDD, they
will be clamped by internal diodes. This product can handle input currents
of greater than 100mA below GND or above VDD without latchup.
5
Cycles
Note 4: AVDD = DRVDD = 3.3V, fSAMPLE =170MHz, differential CLK+/CLK= 2Vpp sine wave, differential analog inputs, unless otherwise noted.
Note 5: Integral nonlinearity is defined as the deviation of a code from a
“best fit straight line” fit to the transfer curve. The deviation is measured
from the center of the quantization band.
Note 6: Offset error is the offset voltage measured from -0.5 LSB when the
output code flickers between 0000 0000 0000 and 1111 1111 1111.
Note 7: Guaranteed by design, not subject to test.
Note 8: Recommended operating conditions.
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LTM2220-AA
TYPICAL PERFORMANCE CHARACTERISTICS
8192 Point FFT, fIN = 30MHz,
–1dB, 170Msps
8192 Point FFT, fIN = 70MHz,
–1dB, 170Msps
0
0
–10
–10
–20
–20
–20
–30
–30
–30
–40
–50
–60
–70
AMPLITUDE (dB)
0
–10
AMPLITUDE (dB)
AMPLITUDE (dB)
8192 Point FFT, fIN = 5MHz, –1dB,
170Msps
–40
–50
–60
–70
–40
–50
–60
–70
–80
–80
–90
–90
–90
–100
–100
–100
–110
–80
–110
0
10
20
30 40 50 60
FREQUENCY (MHz)
70
80
–110
0
10
20
30 40 50 60
FREQUENCY (MHz)
70
2220 G01
0
INL Error
–10
0.8
0.8
–20
0.6
0.6
0.4
0.4
–30
ERROR (LSB)
–70
ERROR (LSB)
1.0
–60
0.2
0
– 0.2
0
– 0.4
– 0.4
– 0.6
– 0.6
–100
– 0.8
– 0.8
– 1.0
10
20
30 40 50 60
FREQUENCY (MHz)
70
80
2220 G04
80
– 0.2
–90
0
70
0.2
–80
–110
30 40 50 60
FREQUENCY (MHz)
DNL Error
1.0
–50
20
2220 G03
0
–40
10
2220 G02
8192 Point FFT, fIN = 140MHz,
–1dB, 170Msps
AMPLITUDE (dB)
80
– 1.0
0
1024
3072
2048
OUTPUT CODE
4096
2220 G05
0
1024
3072
2048
OUTPUT CODE
4096
2220 G06
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LTM2220-AA
PIN FUNCTIONS
NC (Pins 1, 2, 3, 5, 6, 7, 10, 11, 33, 42, 43, 44, 45, 46):
Pin is not connected internally.
AGND (Pins 4, 9, 12, 13, 16, 17, 20, 23, 25, 26, 30,
31, 32, 35, 38, 41, 86, 87, 91, 92, 93, 96, 97, 100):
Analog Ground.
AVDD (Pins 8, 14, 15, 18, 19, 24, 27, 28, 29, 34, 39, 40,
88, 89, 90, 94, 95, 98, 99): 3.3V Analog Supply.
D3+ (Pin 58): D3 True Output Bit.
D4- (Pin 59): D4 Complement Output Bit.
D4+ (Pin 60): D4 True Output Bit.
DCO- (Pin 63): Data Clock Output Complement.
DCO+ (Pin 64): Data Clock Output True.
D5- (Pin 65): D5 Complement Output Bit.
VIN
+ (Pin 21): Positive Analog Input.
D5+ (Pin 66): D5 True Output Bit.
VIN
- (Pin 22): Negative Analog Input.
D6- (Pin 68): D6 Complement Output Bit.
CLK+ (Pin 36): Clock Input. The input sample starts on
the positive edge.
D6+ (Pin 69): D6 True Output Bit.
CLK- (Pin 37): Clock Complement Input. Conversion starts
on the negative edge. Bypass to ground with a 0.1µF
ceramic for a single-ended clock.
D7+ (Pin 71): D7 True Output Bit.
D7- (Pin 70): D7 Complement Output Bit.
D8- (Pin 72): D8 Complement Output Bit.
DRVDD (Pins 47, 54, 62, 75, 83): 3.3V Digital Output
Driver Supply.
D8+ (Pin 73): D8 True Output Bit.
DRGND (Pins 48, 53, 61, 67, 74, 82): Digital Output
Driver Ground.
D9+ (Pin 77): D9 True Output Bit.
D0- (Pin 49): D0 Complement Output Bit (LSB).
D10- (Pin 78): D10 Complement Output Bit.
D0+ (Pin 50): D0 True Output Bit (LSB).
D10+ (Pin 79): D10 True Output Bit.
D1- (Pin 51): D1 Complement Output Bit.
D11- (Pin 80): D11 Complement Output Bit (MSB).
D1+ (Pin 52): D1 True Output Bit.
D11+ (Pin 81): D11 True Output Bit (MSB).
D2- (Pin 55): D2 Complement Output Bit.
OR- (Pin 84): Overrange Output Complement.
D2+ (Pin 56): D2 True Output Bit.
OR+ (Pin 85): Overrange Output True.
D3- (Pin 57): D3 Complement Output Bit.
GND (Exposed Pads): The exposed pads on the bottom of
the package need to be soldered to Analog Ground.
D9- (Pin 76): D9 Complement Output Bit.
TIMING DIAGRAM
tAP
ANALOG
INPUT
N+4
N+2
N
N+3
tH
N+1
tL
CLK–
CLK+
tD
N–5
D0-D11, OR
DCO–
DCO+
N–4
N–3
N–2
N–1
tC
2220 TD01
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LTM2220-AA
APPLICATIONS INFORMATION
DYNAMIC PERFORMANCE
Lower and Upper –3dB Frequencies
Signal-to-Noise Plus Distortion Ratio
The input frequencies at which the amplitude of the reconstructed fundamental is reduced by 3dB for a full scale
input signal. Note that the analog input has a bandpass
response.
The signal-to-noise plus distortion ratio [S/(N + D)] is
the ratio between the RMS amplitude of the fundamental input frequency and the RMS amplitude of all other
frequency components at the ADC output. The output is
band limited to frequencies above DC to below half the
sampling frequency.
Signal-to-Noise Ratio
The signal-to-noise ratio (SNR) is the ratio between the
RMS amplitude of the fundamental input frequency and
the RMS amplitude of all other frequency components
except the first five harmonics and DC.
Intermodulation Distortion
If the ADC input signal consists of more than one spectral
component, the ADC transfer function nonlinearity can
produce intermodulation distortion (IMD) in addition to
Total Harmonic Distortion (THD). IMD is the change in
one sinusoidal input caused by the presence of another
sinusoidal input at a different frequency.
If two pure sine waves of frequencies fa and fb are applied to the ADC input, nonlinearities in the ADC transfer
function can create distortion products at the sum and
difference frequencies of mfa ± nfb, where m and n = 0,
1, 2, 3, etc. The 3rd order intermodulation products are
2fa + fb, 2fb + fa, 2fa – fb and 2fb – fa. The intermodulation distortion is defined as the ratio of the RMS value of
either input tone to the RMS value of the largest 3rd order
intermodulation product.
Spurious Free Dynamic Range (SFDR)
Spurious free dynamic range is the peak harmonic or spurious noise that is the largest spectral component excluding
the input signal and DC. This value is expressed in decibels
relative to the RMS value of a full scale input signal.
Aperture Delay Time
The time from when a rising CLK+ equals the CLK– voltage
to the instant that the input signal is held by the sample
and hold circuit.
Aperture Delay Jitter
The variation in the aperture delay time from conversion
to conversion. This random variation will result in noise
when sampling an AC input. The signal to noise ratio due
to the jitter alone will be:
SNRJITTER = –20log (2π • fIN • tJITTER)
CONVERTER OPERATION
The LTM2220-AA is a CMOS pipelined multistep converter.
The converter has five pipelined ADC stages; a sampled
analog input will result in a digitized value five cycles later
(see the Timing Diagram section). For optimal AC performance the analog inputs should be driven differentially.
For cost sensitive applications, the analog inputs can be
driven single-ended with slightly worse harmonic distortion. The clock input is differential for improved common
mode noise immunity.
The LTM2220-AA is pin compatible with the AD9430 when
used with LVDS outputs, 2’s complement output format
and the 1.536VPP input range.
The LTM2220-AA package contains power supply bypass
capacitors, which makes the part easy to use since it is
insensitive to the PC board layout.
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LTM2220-AA
APPLICATIONS INFORMATION
SAMPLE/HOLD OPERATION AND INPUT DRIVE
Input Drive Impedance
Sample/Hold Operation
As with all high performance, high speed ADCs, the dynamic performance of the LTM2220-AA can be influenced
by the input drive circuitry, particularly the second and
third harmonics. Source impedance and input reactance
can influence SFDR.
Figure 1 shows an equivalent circuit for the LTM2220-AA
CMOS differential sample-and-hold. The analog inputs are
AC coupled to the sample and hold circuit through 0.1µF
capacitors and 1k bias resistors. The 25Ω resistor and
0.5pF capacitor serve two purposes: isolating the drive
circuitry from the sample and hold charging glitches and
limiting the wideband noise at the converter input.
The source impedance should be matched for the differential inputs. Poor matching will result in higher even
order harmonics, especially the second.
Single-Ended Input
Input Drive Circuits
For cost sensitive applications, the analog inputs can be
driven single-ended. With a single-ended input the harmonic distortion and INL will degrade, but the SNR and
DNL will remain unchanged.
Figure 2 shows the LTM2220-AA being driven by an RF
transformer with a center tapped secondary. The secondary
center tap is grounded as shown, but it can also be connected to any DC bias voltage from 0V to 3.6V. Terminating
on the transformer secondary is desirable, as this provides
a common mode path for charging glitches caused by the
sample and hold.
Common Mode Bias
For optimal performance the analog inputs should be driven
differentially. Each input should swing ±0.384V around a
common mode voltage of between 0V and 3.6V.
LTM2220-AA
VDD
0.1µF
25Ω
VIN+
15Ω
VDD
0.5pF
0.1µF
25Ω
VIN–
1k
15Ω
CSAMPLE
1.6pF
CSAMPLE
1.6pF
Driving the Clock Inputs
The noise performance of the LTM2220-AA can depend on
the encode signal quality as much as on the analog input.
The CLK+/CLK– inputs are intended to be driven differentially, primarily for noise immunity from common mode
noise sources. Each input is biased through a 6k resistor
to a 1.6V bias. The bias resistors set the DC operating
point for transformer coupled drive circuits and can set
the logic threshold for single-ended drive circuits.
1k
0.1µF
ANALOG
INPUT
VDD
T1
1:1
VIN+
25Ω
VREF
LTM2220-AA
1.6V
25Ω
VIN–
6k
T1 = M/A-COM ETC1-1T OR EQUIVALENT
CLK+
2220 F02
Figure 2. Single-Ended to Differential
Conversion Using a Transformer
CLK–
6k
1.6V
2220 F01
Figure 1. Equivalent Input Circuit
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LTM2220-AA
APPLICATIONS INFORMATION
Any noise present on the encode signal will result in additional aperture jitter that will be RMS summed with the
inherent ADC aperture jitter.
Maximum and Minimum Encode Rates
1. Differential drive should be used.
The maximum encode rate for the LTM2220-AA is 170Msps.
For the ADC to operate properly, the encode signal should
have a 50% (±20%) duty cycle. Each half cycle must have
at least 2ns for the ADC internal circuitry to have enough
settling time for proper operation.
2. Use as large an amplitude as possible; if transformer
coupled use a higher turns ratio to increase the amplitude.
If the clock is turned off for a long period of time, the duty
cycle stabilizer circuit will require one hundred clock cycles
for the PLL to lock onto the input clock.
3. If the ADC is clocked with a sinusoidal signal, filter the
encode signal to reduce wideband noise.
The lower limit of the LTM2220-AA sample rate is determined by droop of the sample-and-hold circuits. The
pipelined architecture of this ADC relies on storing analog
signals on small valued capacitors. Junction leakage will
discharge the capacitors. The specified minimum operating
frequency for the LTM2220-AA is 1Msps.
In applications where jitter is critical (high input frequencies) take the following into consideration:
4. Balance the capacitance and series resistance at both
encode inputs so that any coupled noise will appear at both
inputs as common mode noise. The clock inputs have a
common mode range of 1.1V to 2.5V. Each input may be
driven from ground to VDD for single-ended drive.
CLK+
VTHRESHOLD = 1.6V
1.6V CLK– LTM2220-AA
VDD
LTM2220-AA
0.1µF
TO INTERNAL
ADC CIRCUITS
VDD
2220 F04
Figure 4. Single-Ended CLK Drive,
Not Recommended for Low Jitter
1.6V BIAS
6k
3.3V
CLK+
0.1µF
MC100LVELT22
1:4
CLOCK
INPUT
VDD
50Ω
1.6V BIAS
3.3V
130Ω
Q0
130Ω
CLK+
D0
6k
CLK– LTM2220-AA
Q0
CLK–
83Ω
83Ω
2220 F05
2220 F03
Figure 3. Transformer Driven CLK+/CLK–
Figure 5. CLK Drive Using a CMOS to PECL Translator
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LTM2220-AA
APPLICATIONS INFORMATION
DIGITAL OUTPUTS
Output Clock
Table 1. Output Codes vs Input Voltage
The ADC has a delayed version of the CLK+ input available as a digital output, DCO. The DCO pin can be used to
synchronize the converter data to the digital system. This
is necessary when using a sinusoidal clock. Data will be
updated as DCO+/DCO– rises and can be latched on the
falling edge of DCO+/DCO–.
VIN+ – VIN–
OR
D11 – D0
>+0.768000V
+0.768000V
+0.767625V
1
0
0
0111 1111 1111
0111 1111 1111
0111 1111 1110
+0.000375V
0.000000V
–0.000375V
–0.000750V
0
0
0
0
0000 0000 0001
0000 0000 0000
1111 1111 1111
1111 1111 1110
–0.767625V
–0.768000V
<–0.768000V
0
0
1
1000 0000 0001
1000 0000 0000
1000 0000 0000
Digital Output Buffers
Figure 6 shows an equivalent circuit for a differential
output pair in the LVDS output mode. A 3.5mA current is
steered from OUT+ to OUT– or vice versa which creates a
±350mV differential voltage across the 100Ω termination
resistor at the LVDS receiver. A feedback loop regulates
the common mode output voltage to 1.25V. For proper
operation each LVDS output pair needs an external 100Ω
termination resistor, even if the signal is not used (such
as OR+/OR– or DCO+/DCO–). To minimize noise the PC
board traces for each LVDS output pair should be routed
close together. To minimize clock skew all LVDS PC board
traces should have about the same length.
Data Format
The LTM2220-AA parallel digital output has 2’s complement
format. Table 1 shows the relationship between the analog
input voltage, the digital data bits and the overrange bit.
LTM2220-AA
DRVDD
Output Driver Power
Separate output power and ground pins allow the output
drivers to be isolated from the analog circuitry. DRVDD
should be connected to a 3.3V supply and DRGND should
be connected to GND.
GROUNDING AND BYPASSING
The LTM2220-AA requires a printed circuit board with a
clean unbroken ground plane. A multilayer board with an
internal ground plane is recommended. Layout for the
printed circuit board should ensure that digital and analog
signal lines are separated as much as possible. In particular,
care should be taken not to run any digital signal alongside
an analog signal or underneath the ADC.
The LTM2220-AA differential inputs should run parallel
and close to each other. The input traces should be as
short as possible to minimize capacitance and to minimize
noise pickup.
The LTM2220-AA package contains power supply bypass
capacitors on AVDD and DRVDD. External bypass capacitors can be added for additional low-frequency noise
rejection, but they are not required if the power supplies
come from quiet linear voltage regulators.
HEAT TRANSFER
D
+
D
OUT+
–
10k
10k
100Ω
1.25V
OUT–
D
D
3.5mA
DRGND
LVDS
RECEIVER
Most of the heat generated by the LTM2220-AA is transferred from the die through the bottom-side exposed
pads and package leads onto the printed circuit board.
For good electrical and thermal performance, the exposed
pads should be soldered to a large grounded pad on the
PC board. It is critical that all ground pins are connected
to a ground plane of sufficient area.
2220 F06
Figure 6. Digital Output
2220aaf
10
LTM2220-AA
PACKAGE DESCRIPTION
SiPLGA Package
100-Lead (16mm × 16mm)
6.000
5.500
5.000
4.500
4.000
3.500
3.000
2.500
2.000
1.500
1.000
0.500
0.000
0.500
1.000
1.500
2.000
2.500
3.000
3.500
4.000
4.500
5.000
5.500
6.000
(Reference LTC DWG # 05-08-1802 Rev Ø)
26
aaa Z
25
4
X
Y
PAD 1
CORNER
3.1245
1.045
3.1245
1.045
51
6.000
5.500
5.000
4.500
4.000
3.500
3.000
2.500
2.000
1.500
1.000
0.500
0.000
0.500
1.000
1.500
2.000
2.500
3.000
3.500
4.000
4.500
5.000
5.500
6.000
15.90 – 16.10
(2X)
50
3.1245
3.1245
1.045
1.045
1.045
1.045
3.1245
3.1245
3.1245
1.045
1.045
3.1245
15.9 – 16.1
75
1
aaa Z
100
DETAILED PAD LAYOUT
1.93 – 2.13
0.315 – 0.385
0.218 – 0.278 (b)
(2X)
76
TOP VIEW
11.90 – 12.10
eee M X Y
26
50
ROWS
AF
0.05 – 0.15
25
51
1.120 – 1.180
1.313 – 1.383
PAD
AE
AD
AC
AB
AA
Y
W
V
0.5
BASIC
DETAIL B
U
T
S
R
11.90 – 12.10
P
N
M
L
K
J
MOLD
CAP
SUBSTRATE
H
G
F
E
D
0.33 – 0.43
C
1.60 – 1.70
Z
bbb Z
1
5
75
DETAIL B
B
A
100
DETAIL A
DETAIL A
COLUMNS
1
76
3
2
5
4
7
6
9
8
11
10
13
12
15
14
17
16
19
18
21
20
23
22
3
25
24
26
BOTTOM VIEW
NOTES:
1. DIMENSIONING AND TOLERANCING PER ASME Y14.5M-1994
2. ALL DIMENSIONS ARE IN MILLIMETERS
3
LAND DESIGNATION PER JESD MO-222, SPP-010
4
DETAILS OF PAD #1 IDENTIFIER ARE OPTIONAL,
BUT MUST BE LOCATED WITHIN THE ZONE INDICATED.
THE PAD #1 IDENTIFIER MAY BE EITHER A MOLD
OR MARKED FEATURE
5
PRIMARY DATUM -Z- IS SEATING PLANE
SYMBOL TOLERANCE
0.10
aaa
0.10
bbb
0.03
eee
10_10_06
6. DIMENSION (b) IS MEASURED AT THE MAXIMUM LAND
WIDTH, PARALLEL TO PRIMARY DATUM -Z7. TOTAL NUMBER OF PADS: 104 TOTAL (100 PERIPHERAL + 4 COMMON CENTER)
2220aaf
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
11
LTM2220-AA
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTC2220
12-Bit, 170Msps, 3.3V ADC, LVDS Outputs
890mW, 67.7dB SNR, 84dB SFDR, 64-Pin QFN Package
LTC2242-12
12-Bit, 250Msps, 2.5V ADC, LVDS Outputs
740mW, 65.4dB SNR, 84dB SFDR, 64-Pin QFN Package
LT1993-2
High Speed Differential Op Amp
800MHz BW, 70dBc Distortion at 70MHz, 6dB Gain
2220aaf
12 Linear Technology Corporation
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