LTC2245
14-Bit, 10Msps
Low Power 3V ADC
FEATURES
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DESCRIPTIO
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Sample Rate: 10Msps
Single 3V Supply (2.7V to 3.4V)
Low Power: 60mW
74.4dB SNR
90dB SFDR
No Missing Codes
Flexible Input: 1V
P-P
to 2V
P-P
Range
575MHz Full Power Bandwidth S/H
Clock Duty Cycle Stabilizer
Shutdown and Nap Modes
Pin Compatible Family
125Msps: LTC2253 (12-Bit), LTC2255 (14-Bit)
105Msps: LTC2252 (12-Bit), LTC2254 (14-Bit)
80Msps: LTC2229 (12-Bit), LTC2249 (14-Bit)
65Msps: LTC2228 (12-Bit), LTC2248 (14-Bit)
40Msps: LTC2227 (12-Bit), LTC2247 (14-Bit)
25Msps: LTC2226 (12-Bit), LTC2246 (14-Bit)
10Msps: LTC2225 (12-Bit), LTC2245 (14-Bit)
32-Pin (5mm
×
5mm) QFN Package
The LTC
®
2245 is a 14-bit 10Msps, low power 3V A/D
converter designed for digitizing high frequency, wide
dynamic range signals. The LTC2245 is perfect for de-
manding imaging and communications applications with
AC performance that includes 74.4dB SNR and 90dB
SFDR for signals well beyond the Nyquist frequency.
DC specs include
±1LSB
INL (typ),
±0.5LSB
DNL (typ) and
no missing codes over temperature. The transition noise
is a low 1LSB
RMS
.
A single 3V supply allows low power operation. A separate
output supply allows the outputs to drive 0.5V to 3.6V
logic.
A single-ended CLK input controls converter operation. An
optional clock duty cycle stabilizer allows high perfor-
mance at full speed for a wide range of clock duty cycles.
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
APPLICATIO S
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Wireless and Wired Broadband Communication
Imaging Systems
Spectral Analysis
Portable Instrumentation
TYPICAL APPLICATIO
REFH
REFL
FLEXIBLE
REFERENCE
INL ERROR (LSB)
OV
DD
+
ANALOG
INPUT
INPUT
S/H
–
14-BIT
PIPELINED
ADC CORE
CORRECTION
LOGIC
OUTPUT
DRIVERS
D13
•
•
•
D0
OGND
CLOCK/DUTY
CYCLE
CONTROL
2245 TA01
CLK
U
Typical INL, 2V Range
2.0
1.5
1.0
0.5
0
–0.5
–1.0
–1.5
–2.0
0
4096
8192
CODE
12288
16384
2245 G01
U
U
2245fa
1
LTC2245
ABSOLUTE
AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
OV
DD
= V
DD
(Notes 1, 2)
Supply Voltage (V
DD
) ................................................. 4V
Digital Output Ground Voltage (OGND) ....... –0.3V to 1V
Analog Input Voltage (Note 3) ..... –0.3V to (V
DD
+ 0.3V)
Digital Input Voltage .................... –0.3V to (V
DD
+ 0.3V)
Digital Output Voltage ................ –0.3V to (OV
DD
+ 0.3V)
Power Dissipation ............................................ 1500mW
Operating Temperature Range
LTC2245C ............................................... 0°C to 70°C
LTC2245I .............................................–40°C to 85°C
Storage Temperature Range ..................–65°C to 125°C
SENSE
MODE
V
CM
D13
D12
32 31 30 29 28 27 26 25
A
IN+
1
A
IN–
2
REFH 3
REFH 4
REFL 5
REFL 6
V
DD
7
GND 8
9 10 11 12 13 14 15 16
33
24 D10
23 D9
22 D8
21 OV
DD
20 OGND
19 D7
18 D6
17 D5
OE
D0
D1
D2
D3
CLK
UH PACKAGE
32-LEAD (5mm
×
5mm) PLASTIC QFN
T
JMAX
= 125°C,
θ
JA
= 34°C/W
EXPOSED PAD IS GND (PIN 33)
MUST BE SOLDERED TO PCB
SHDN
ORDER PART NUMBER
LTC2245CUH
LTC2245IUH
QFN PART MARKING
2245*
Order Options
Tape and Reel: Add #TR
Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF
Lead Free Part Marking:
http://www.linear.com/leadfree/
Consult LTC Marketing for parts specified with wider operating temperature ranges.
*The temperature grade is identified by a label on the shipping container.
CO VERTER CHARACTERISTICS
PARAMETER
Resolution
(No Missing Codes)
Integral
Linearity Error
Differential
Linearity Error
Offset Error
Gain Error
Offset Drift
Full-Scale Drift
Transition Noise
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Note 4)
CONDITIONS
●
MIN
14
–4
–1
–12
–2.5
D4
D11
V
DD
OF
TYP
MAX
UNITS
Bits
Differential Analog Input
(Note 5)
Differential Analog Input
(Note 6)
External Reference
Internal Reference
External Reference
SENSE = 1V
●
●
●
●
±1
±0.5
±2
±0.5
±10
±30
±5
1
4
1
12
2.5
µV/°C
ppm/°C
ppm/°C
LSB
RMS
2245fa
2
U
LSB
LSB
mV
%FS
W
U
U
W W
W
U
LTC2245
A ALOG I PUT
SYMBOL
V
IN
V
IN,CM
I
IN
I
SENSE
I
MODE
t
AP
t
JITTER
CMRR
PARAMETER
The
●
denotes the specifications which apply over the full operating temperature range, otherwise
specifications are at T
A
= 25°C. (Note 4)
CONDITIONS
2.7V < V
DD
< 3.4V (Note 7)
Differential Input (Note 7)
Single Ended Input (Note 7)
0V < A
IN+
, A
IN–
< V
DD
0V < SENSE < 1V
●
●
●
●
●
●
Analog Input Range (A
IN+
– A
IN–
)
Analog Input Common Mode (A
IN+
+ A
IN–
)/2
Analog Input Leakage Current
SENSE Input Leakage
MODE Pin Leakage
Sample-and-Hold Acquisition Delay Time
Sample-and-Hold Acquisition Delay Time Jitter
Analog Input Common Mode Rejection Ratio
DY A IC ACCURACY
SYMBOL
SNR
SFDR
SFDR
S/(N+D)
I
MD
PARAMETER
Signal-to-Noise Ratio
Spurious Free Dynamic Range
2nd or 3rd Harmonic
Spurious Free Dynamic Range
4th Harmonic or Higher
The
●
denotes the specifications which apply over the full operating temperature range,
otherwise specifications are at T
A
= 25°C. A
IN
= –1dBFS. (Note 4)
CONDITIONS
5MHz Input
70MHz Input
5MHz Input
70MHz Input
5MHz Input
70MHz Input
5MHz Input
70MHz Input
f
IN1
= 4.3MHz, f
IN2
= 4.6MHz
●
●
●
●
Signal-to-Noise Plus Distortion Ratio
Intermodulation Distortion
I TER AL REFERE CE CHARACTERISTICS
PARAMETER
V
CM
Output Voltage
V
CM
Output Tempco
V
CM
Line Regulation
V
CM
Output Resistance
CONDITIONS
I
OUT
= 0
U
U
W U
U
U
MIN
1
0.5
–1
–3
–3
TYP
1.5
1.5
MAX
1.9
2
1
3
3
UNITS
V
V
V
µA
µA
µA
ns
ps
RMS
dB
±0.5V
to
±1V
0
0.2
80
MIN
72.3
76
84
71.7
TYP
74.4
73.2
90
85
95
95
74.4
73.1
90
MAX
UNITS
dB
dB
dB
dB
dB
dB
dB
dB
dB
U
(Note 4)
MIN
1.475
TYP
1.500
±25
3
4
MAX
1.525
UNITS
V
ppm/°C
mV/V
Ω
2.7V < V
DD
< 3.4V
–1mA < I
OUT
< 1mA
2245fa
3
LTC2245
DIGITAL I PUTS A D DIGITAL OUTPUTS
SYMBOL
V
IH
V
IL
I
IN
C
IN
OV
DD
= 3V
C
OZ
I
SOURCE
I
SINK
V
OH
V
OL
OV
DD
= 2.5V
V
OH
V
OL
OV
DD
= 1.8V
V
OH
V
OL
High Level Output Voltage
Low Level Output Voltage
I
O
= –200µA
I
O
= 1.6mA
1.79
0.09
V
V
High Level Output Voltage
Low Level Output Voltage
I
O
= –200µA
I
O
= 1.6mA
2.49
0.09
V
V
Hi-Z Output Capacitance
Output Source Current
Output Sink Current
High Level Output Voltage
Low Level Output Voltage
OE = High (Note 7)
V
OUT
= 0V
V
OUT
= 3V
I
O
= –10µA
I
O
= –200µA
I
O
= 10µA
I
O
= 1.6mA
●
●
The
●
denotes the specifications which apply over the
full operating temperature range, otherwise specifications are at T
A
= 25°C. (Note 4)
PARAMETER
High Level Input Voltage
Low Level Input Voltage
Input Current
Input Capacitance
CONDITIONS
V
DD
= 3V
V
DD
= 3V
V
IN
= 0V to V
DD
(Note 7)
●
●
●
LOGIC INPUTS (CLK, OE, SHDN)
2
0.8
–10
3
10
V
V
µA
pF
LOGIC OUTPUTS
3
50
50
2.7
2.995
2.99
0.005
0.09
0.4
pF
mA
mA
V
V
V
V
POWER REQUIRE E TS
SYMBOL
V
DD
OV
DD
I
VDD
P
DISS
P
SHDN
P
NAP
PARAMETER
Analog Supply Voltage
Output Supply Voltage
Supply Current
Power Dissipation
Shutdown Power
Nap Mode Power
The
●
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. (Note 8)
CONDITIONS
(Note 9)
(Note 9)
●
●
●
●
4
U W
U
U
MIN
TYP
MAX
UNITS
MIN
2.7
0.5
TYP
3
3
20
60
2
15
MAX
3.4
3.6
23
69
UNITS
V
V
mA
mW
mW
mW
SHDN = H, OE = H, No CLK
SHDN = H, OE = L, No CLK
2245fa
LTC2245
The
●
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. (Note 4)
SYMBOL
f
s
t
L
PARAMETER
Sampling Frequency
CLK Low Time
CONDITIONS
(Note 9)
Duty Cycle Stabilizer Off
Duty Cycle Stabilizer On
(Note 7)
Duty Cycle Stabilizer Off
Duty Cycle Stabilizer On
(Note 7)
C
L
= 5pF (Note 7)
C
L
= 5pF (Note 7)
(Note 7)
●
●
●
●
●
TI I G CHARACTERISTICS
t
H
t
AP
t
D
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 GND and OGND
wired together (unless otherwise noted).
Note 3:
When these pin voltages are taken below GND or above V
DD
, they
will be clamped by internal diodes. This product can handle input currents
of greater than 100mA below GND or above V
DD
without latchup.
Note 4:
V
DD
= 3V, f
SAMPLE
= 10MHz, input range = 2V
P-P
with differential
drive, unless otherwise noted.
TYPICAL PERFOR A CE CHARACTERISTICS
Typical INL, 2V Range
2.0
1.5
1.0
DNL ERROR (LSB)
INL ERROR (LSB)
0.5
0
–0.5
–1.0
–1.5
–2.0
0
4096
8192
CODE
12288
16384
2245 G01
0.2
0
–0.2
–0.4
AMPLITUDE (dB)
U W
UW
MIN
1
40
5
40
5
TYP
50
50
50
50
0
MAX
10
500
500
500
500
UNITS
MHz
ns
ns
ns
ns
ns
CLK High Time
Sample-and-Hold Aperture Delay
CLK to DATA delay
Data Access Time After OE↓
BUS Relinquish Time
●
●
●
1.4
2.7
4.3
3.3
5
5.4
10
8.5
ns
ns
ns
Cycles
Note 5:
Integral nonlinearity is defined as the deviation of a code from a
straight line passing through the actual endpoints of 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 00 0000 0000 0000 and
11 1111 1111 1111.
Note 7:
Guaranteed by design, not subject to test.
Note 8:
V
DD
= 3V, f
SAMPLE
= 10MHz, input range = 1V
P-P
with
differential drive.
Note 9:
Recommended operating conditions.
Typical DNL, 2V Range
1.0
8192 Point FFT, f
IN
= 5.1MHz,
–1dB, 2V Range
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
–120
0.8
0.6
0.4
–0.6
–0.8
–1.0
0
4096
8192
CODE
12288
16384
2245 G02
0
1
3
2
FREQUENCY (MHz)
4
5
2245 G03
2245fa
5
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