Document
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FEATURES
■ Sample Rate: 125Msps/105Msps ■ Single 3V Supply (2.85V to 3.4V) ■ Low Power: 395mW/320mW ■ 61.6dB SNR ■ 85dB SFDR ■ No Missing Codes ■ Flexible Input: 1VP-P to 2VP-P Range ■ 640MHz Full Power Bandwidth S/H ■ Clock Duty Cycle Stabilizer ■ Shutdown and Nap Modes ■ Pin Compatible Family:
125Msps: LTC2251 (10-Bit), LTC2253 (12-Bit) 105Msps: LTC2250 (10-Bit), LTC2252 (12-Bit) 80Msps: LTC2239 (10-Bit), LTC2229 (12-Bit) 65Msps: LTC2238 (10-Bit), LTC2228 (12-Bit) 40Msps: LTC2237 (10-Bit), LTC2227 (12-Bit) 25Msps: LTC2236 (10-Bit), LTC2226 (12-Bit) ■ 32-Pin (5mm × 5mm) QFN Package
U APPLICATIO S
■ Wireless and Wired Broadband Communication ■ Imaging Systems ■ Ultrasound ■ Spectral Analysis ■ Portable Instrumentation
LTC2251/LTC2250
10-Bit, 125/105Msps Low Noise 3V ADCs
DESCRIPTIO
The LTC®2251/LTC2250 are 10-bit 125Msps/105Msps, low noise 3V A/D converters designed for digitizing high frequency, wide dynamic range signals. The LTC2251/ LTC2250 are perfect for demanding imaging and communications applications with AC performance that includes 61.6dB SNR and 85dB SFDR for signals at the Nyquist frequency.
DC specs include ±0.1LSB INL (typ), ±0.05LSB DNL (typ) and ±0.6LSB INL, ±0.6LSB DNL over temperature. The transition noise is a low 0.08LSBRMS.
A single 3V supply allows low power operation. A separate output supply allows the outputs to drive 0.5V to 3.3V logic.
A single-ended CLK input controls converter operation. An optional clock duty cycle stabilizer allows high performance 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.
TYPICAL APPLICATIO
REFH REFL
ANALOG INPUT
FLEXIBLE REFERENCE
+
INPUT S/H
–
CLOCK/DUTY CYCLE
CONTROL
CLK
10-BIT PIPELINED ADC CORE
CORRECTION LOGIC
OUTPUT DRIVERS
OVDD
D9 • • • D0
OGND
22510 TA01
SNR (dBFS)
LTC2251: SNR vs Input Frequency, –1dB, 2V Range, 125Msps
65
64
63
62
61
60
59
58
57
56
55 0
50 100 150 200 250 300 350 INPUT FREQUENCY (MHz) 22510 G09
22510fa
1
U U WW W
LTC2251/LTC2250
ABSOLUTE AXI U RATI GS
OVDD = VDD (Notes 1, 2)
Supply Voltage (VDD) ................................................. 4V Digital Output Ground Voltage (OGND) ....... –0.3V to 1V Analog Input Voltage (Note 3) ..... –0.3V to (VDD + 0.3V) Digital Input Voltage .................... –0.3V to (VDD + 0.3V) Digital Output Voltage ................ –0.3V to (OVDD + 0.3V) Power Dissipation ............................................ 1500mW Operating Temperature Range
LTC2251C, LTC2250C ............................. 0°C to 70°C LTC2251I, LTC2250I ...........................–40°C to 85°C Storage Temperature Range ..................–65°C to 125°C
UW U PACKAGE/ORDER I FOR ATIO
TOP VIEW
VDD VCM SENSE MODE OF D9 D8 D7
AIN+ 1 AIN– 2
32 31 30 29 28 27 26 25 24 D6 23 D5
REFH 3
22 D4
REFH 4 REFL 5
33
21 OVDD
20 OGND
REFL 6
19 D3
VDD 7 GND 8
18 D2 17 D1
9 10 11 12 13 14 1.