19-1981; Rev 1; 5/04
KIT
ATION
EVALU
BLE
AVAILA
12-Bit, 60Msps, 3.3V, Low-Power ADC
with Internal Reference
MAX1420
General Description
Features
♦
3.3V Single Power Supply
♦
67dB SNR at f
IN
= 5MHz
♦
66dB SNR at f
IN
= 15MHz
♦
Internal 2.048V Precision Bandgap Reference
♦
Differential, Wideband Input T/H Amplifier
♦
Power-Down Modes
218mW (Reference Shutdown Mode)
10µW (Shutdown Mode)
♦
Space-Saving 48-Pin TQFP Package
The MAX1420, 3.3V, 12-bit analog-to-digital converter
(ADC) features a fully-differential input, pipelined, 12-
stage ADC architecture with wideband track-and-hold
(T/H) and digital error correction, incorporating a fully-
differential signal path. The MAX1420 is optimized for
low-power, high dynamic performance applications in
imaging and digital communications. The converter
operates from a single 3.3V supply, and consumes only
221mW. The fully-differential input stage has a small
signal -3dB bandwidth of 400MHz and may be operat-
ed with single-ended inputs.
An internal 2.048V precision bandgap reference sets
the full-scale range of the ADC. A flexible reference
structure accommodates an internal reference, or
externally applied buffered or unbuffered reference for
applications that require increased accuracy and a dif-
ferent input voltage range.
In addition to low operating power, the MAX1420 fea-
tures two power-down modes: reference power-down
and shutdown mode. In reference power-down, the
internal bandgap reference is deactivated, which
results in a typical 2mA supply current reduction. A full
shutdown mode is available to maximize power savings
during idle periods.
The MAX1420 provides parallel, offset binary, CMOS-
compatible three-state outputs.
The MAX1420 is available in a 7mm x 7mm x 1.4mm,
48-pin TQFP package, and is specified over the com-
mercial (0°C to +70°C) and the extended industrial
(-40°C to +85°C) temperature range.
Ordering Information
PART
MAX1420CCM
MAX1420ECM
TEMP RANGE
0°C to +70°C
-40°C to +85°C
PIN-PACKAGE
48 TQFP
48 TQFP
Pin Configuration
AGND
AV
DD
CML
REFN
REFP
REFIN
AV
DD
AGND
PD
OE
D11
42
41
40
39
38
Pin-compatible lower speed versions of the MAX1420
are also available. Please refer to the MAX1421 data
sheet for 40Msps and the MAX1422 data sheet for
20Msps.
48
47
46
45
44
43
________________________Applications
Medical Ultrasound Imaging
CCD Pixel Processing
IR Focal Plane Arrays
Radar
IF and Baseband Digitization
AGND
AV
DD
AV
DD
AGND
AGND
INP
INN
AGND
AGND
AV
DD
AV
DD
AGND
37
D10
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
36
35
34
33
32
31
30
29
28
27
26
25
MAX1420
D9
D8
D7
D6
DV
DD
DV
DD
DGND
DGND
D5
D4
D3
D2
Functional diagram appears at end of data sheet.
48-TQFP
________________________________________________________________
Maxim Integrated Products
AV
DD
DV
DD
DGND
D0
D1
AGND
AV
DD
AV
DD
AGND
CLK
CLK
AGND
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
12-Bit, 60Msps, 3.3V, Low-Power ADC
with Internal Reference
MAX1420
ABSOLUTE MAXIMUM RATINGS
AV
DD
, DV
DD
to AGND ..............................................-0.3V to +4V
DV
DD
, AV
DD
to DGND..............................................-0.3V to +4V
DGND to AGND.....................................................-0.3V to +0.3V
INP, INN, REFP, REFN, REFIN,
CML, CLK,
CLK
....................(AGND - 0.3V) to (AV
DD
+ 0.3V)
D0–D11,
OE,
PD .....................(DGND - 0.3V) to (DV
DD
+ 0.3V)
Continuous Power Dissipation (T
A
= +70°C)
48-Pin TQFP (derate 21.7mW/°C above +70°C)........1789mW
Operating Temperature Ranges
MAX1420CCM ....................................................0°C to +70°C
MAX1420ECM .................................................-40°C to +85°C
Maximum Junction Temperature .....................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
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 in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
AVDD
= V
DVDD
= 3.3V, AGND = DGND = 0, V
IN
= ±1.024V, differential input voltage at -0.5dBFS, internal reference, f
CLK
=
62.5MHz (50% duty cycle); digital output load C
L
= 10pF,
≥+25°C
guaranteed by production test, <+25°C guaranteed by design and
characterization. Typical values are at T
A
= +25°C.)
PARAMETER
DC ACCURACY
Resolution
Differential Nonlinearity
Integral Nonlinearity
Mid-scale Offset
Mid-scale Offset Temperature
Coefficient
RES
DNL
INL
MSO
MSOTC
Internal reference (Note 1)
Gain Error
GE
External reference applied to REFIN
(Note 2)
External reference applied to REFP,
CML, and REFN (Note 3)
Gain Error Temperature
Coefficient
GETC
External reference applied to REFP, CML,
and REFN (Note 3)
f
IN
= 5MHz
f
IN
= 15MHz, T
A
=+25°C
f
IN
= 5MHz
f
IN
= 15MHz, T
A
=+25°C
f
IN
= 5MHz
f
IN
= 15MHz, T
A
=+25°C
f
IN
= 5MHz
f
IN
= 15MHz, T
A
=+25°C
f
IN
= 5MHz
f
IN
= 15MHz
f
IN1
= 11.566036MHz,
f
IN2
= 13.4119138MHz (Note 4)
58.5
64
62
-5
-5
-1.5
100 x 106
TA = +25°C, no missing codes
TA = T
MIN
to T
MAX
TA = T
MIN
to T
MAX
-3
-1
±0.5
±2
.75
3 x 10-4
±0.1
±0.2
5
5
1.5
%/°C
3
12
1
Bits
LSB
LSB
%FSR
%/°C
%FSR
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
DYNAMIC PERFORMANCE
(f
CLK
= 60MHz, 4096-point FFT)
Signal-to-Noise Ratio
Spurious-Free Dynamic Range
Total Harmonic Distortion
Signal-to-Noise and Distortion
Effective Number of Bits
Two-Tone
Intermodulation Distortion
SNR
SFDR
THD
SINAD
ENOB
IMD
67
66
72
72
-70
-69
64.5
63
10.4
10.2
-74
-62
dB
dBc
dBc
dB
Bits
dBc
2
_______________________________________________________________________________________
12-Bit, 60Msps, 3.3V, Low-Power ADC
with Internal Reference
ELECTRICAL CHARACTERISTICS (continued)
(V
AVDD
= V
DVDD
= 3.3V, AGND = DGND = 0, V
IN
= ±1.024V, differential input voltage at -0.5dBFS, internal reference, f
CLK
=
62.5MHz (50% duty cycle); digital output load C
L
= 10pF,
≥+25°C
guaranteed by production test, <+25°C guaranteed by design and
characterization. Typical values are at T
A
= +25°C.)
PARAMETER
Differential Gain
Differential Phase
ANALOG INPUTS
(INP, INN, CML)
Input Resistance
Input Capacitance
Common-Mode Input Level
(Note 5)
Common-Mode Input Voltage
Range (Note 5)
Differential Input Range
Small-Signal Bandwidth
Large-Signal Bandwidth
Overvoltage Recovery
R
IN
C
IN
V
CML
V
CMVR
V
IN
BW
-3dB
FPBW
-3dB
OVR
V
INP
- V
INN
(Note 6)
(Note 7)
(Note 7)
1.5 x FS input
Either input to ground
Either input to ground
22
4
V
AVDD
x 0.5
V
CML
±
5%
±V
DIFF
400
150
1
kΩ
pF
V
V
V
MHz
MHz
Clock
cycles
SYMBOL
DG
DP
CONDITIONS
MIN
TYP
±1
±0.25
MAX
UNITS
%
Degrees
MAX1420
INTERNAL REFERENCE
(REFIN bypassed with 0.22µF in parallel with 1nF)
Common-Mode Reference
Voltage
Positive Reference Voltage
Negative Reference Voltage
Differential Reference Voltage
Differential Reference
Temperature Coefficient
REFIN Input Resistance
REFIN Input Capacitance
REFIN Reference Input Voltage
Differential Reference Voltage
V
CML
V
REFP
V
REFN
V
DIFF
REFTC
At CML
At REFP
At REFN
(Note 6)
V
AVDD
_ 0.5
V
CML
+ 0.512
V
CML
- 0.512
1.024 ±5%
±100
V
V
V
V
ppm/°C
EXTERNAL REFERENCE
(V
REFIN
= 2.048V)
R
IN
C
IN
V
REFIN
V
DIFF
(Note 6)
0.92 x
V
REFIN
/2
-200
15
(Note 8)
5
10
2.048
±10%
V
REFIN
/2
1.08 x
V
REFIN
/2
200
kΩ
pF
V
V
EXTERNAL REFERENCE
(V
REFIN
= 0, reference voltage applied to REFP, REFN, and CML)
REFP, REFN, CML Input Current
REFP, REFN, CML Input
Capacitance
I
IN
C
IN
µA
pF
_______________________________________________________________________________________
3
12-Bit, 60Msps, 3.3V, Low-Power ADC
with Internal Reference
MAX1420
ELECTRICAL CHARACTERISTICS (continued)
(V
AVDD
= V
DVDD
= 3.3V, AGND = DGND = 0, V
IN
= ±1.024V, differential input voltage at -0.5dBFS, internal reference, f
CLK
=
62.5MHz (50% duty cycle); digital output load C
L
= 10pF,
≥+25°C
guaranteed by production test, <+25°C guaranteed by design and
characterization. Typical values are at T
A
= +25°C.)
PARAMETER
Differential Reference Voltage
Range
CML Input Voltage Range
REFP Input Voltage Range
REFN Input Voltage Range
DIGITAL INPUTS
(CLK, CLK, PD, OE)
Input Logic High
Input Logic Low
V
IH
V
IL
CLK,
CLK
Input Current
Input Capacitance
DIGITAL OUTPUTS
(D0–D11)
Output Logic High
Output Logic Low
Three-State Leakage
Three-State Capacitance
POWER REQUIREMENTS
Analog Supply Voltage
Digital Supply Voltage
Analog Supply Current
Analog Supply Current with
Internal Reference in Shutdown
Analog Shutdown Current
Digital Supply Current
Digital Shutdown Current
Power Dissipation
P
DISS
I
DVDD
PD = V
DVDD
Analog power dissipation
221
V
AVDD
V
DVDD
I
AVDD
V
REFIN
= 0
PD = D
VDD
3.135
2.7
3.3
3.3
67
66
10
8
20
258
3.465
3.63
78
76
20
V
V
mA
mA
µA
mA
µA
mW
V
OH
V
OL
IOH = 200µA
IOL = -200µA
V
DVDD
- 0.5
0
-10
2
V
DVDD
0.5
10
V
V
µA
pF
PD
OE
-20
-20
10
±330
20
20
pF
µA
0.7 x
V
DVDD
0.3 x
V
DVDD
V
V
SYMBOL
V
DIFF
V
CML
V
REFP
V
REFN
(Note 6)
CONDITIONS
MIN
TYP
1.024
±10%
1.65
±10%
VCML +
V
DIFF
/2
VCML -
V
DIFF
/2
MAX
UNITS
V
V
V
V
4
_______________________________________________________________________________________
12-Bit, 60Msps, 3.3V, Low-Power ADC
with Internal Reference
ELECTRICAL CHARACTERISTICS (continued)
(V
AVDD
= V
DVDD
= 3.3V, AGND = DGND = 0, V
IN
= ±1.024V, differential input voltage at -0.5dBFS, internal reference, f
CLK
=
62.5MHz (50% duty cycle); digital output load C
L
= 10pF,
≥+25°C
guaranteed by production test, <+25°C guaranteed by design and
characterization. Typical values are at T
A
= +25°C.)
PARAMETER
Power Dissipation In Shutdown
Power-Supply Rejection Ratio
TIMING CHARACTERISTICS
Maximum Clock Frequency
Clock High
Clock Low
Pipeline Delay (Latency)
Aperture Delay
Aperture Jitter
Data Output Delay
Bus Enable Time
Bus Disable Time
tAD
tAJ
tOD
tBE
tBD
fCLK
tCH
tCL
60
Figure 6, clock period 16.667ns
Figure 6, clock period 16.667ns
Figure 6
Figure 10
Figure 10
Figure 6
Figure 5
Figure 5
5
8.33
8.33
7
2
2
10
5
5
14
MHz
ns
ns
Clock
cycles
ns
ps
ns
ns
ns
SYMBOL
PDISS
PSRR
(Note 9)
CONDITIONS
PD = VDVDD
MIN
TYP
10
±1
MAX
UNITS
µW
mV/V
MAX1420
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
Note 8:
Note 9:
Internal reference, REFIN bypassed to AGND with a combination of 0.22µF in parallel with 1nF capacitor.
External 2.048V reference applied to REFIN.
Internal reference disabled. V
REFIN
= 0, V
REFP
= 2.162V, V
CML
= 1.65V, and V
REFN
= 1.138V.
IMD is measured with respect to either of the fundamental tones.
Specifies the common-mode range of the differential input signal supplied to the MAX1420.
V
DIFF
= V
REFP
- V
REFN
.
Input bandwidth is measured at a -3dB level.
V
REFIN
is internally biased to 2.048V through a 10kΩ resistor.
Measured as the ratio of the change in mid-scale offset voltage for a ±5% change in V
AVDD
, using the internal reference.
Typical Operating Characteristics
(V
AVDD
= V
DVDD
= 3.3V, AGND = DGND = 0, V
IN
= ±1.024V, differential input drive, A
IN
= -0.5dBFS, f
CLK
= 60.006MHz (50% duty
cycle), digital output load C
L
= 10pF, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
FFT PLOT (8192-POINT DATA RECORD)
MAX1420 toc01
FFT PLOT (8192-POINT DATA RECORD)
MAX1420 toc02
FFT PLOT (8192-POINT DATA RECORD)
f
IN
= 37.7012MHz
-20
AMPLITUDE (dB)
-40
HD3
-60
-80
-100
-120
HD2
MAX1420 toc03
0
f
IN
= 5.5449MHz
-20
AMPLITUDE (dB)
-40
-60
-80
-100
-120
0
5
10
15
20
25
HD2
0
f
IN
= 13.4119MHz
-20
AMPLITUDE (dB)
-40
-60
-80
-100
-120
HD2
HD3
0
HD3
30
0
5
10
15
20
25
30
0
5
10
15
20
25
30
ANALOG INPUT FREQUENCY (MHz)
ANALOG INPUT FREQUENCY (MHz)
ANALOG INPUT FREQUENCY (MHz)
_______________________________________________________________________________________
5
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