Document
FEATURES
n Integrated Dual 14-Bit ADCs n Sample Rate: 125Msps n Single 3V Supply (2.85V to 3.4V) n Low Power: 790mW n 72.4dB SNR, 88dB SFDR n 110dB Channel Isolation at 100MHz n Flexible Input: 1VP-P to 2VP-P Range n 640MHz Full Power Bandwidth S/H n Clock Duty Cycle Stabilizer n Shutdown and Nap Modes n Data Ready Output Clock n Pin Compatible Family
125Msps: LTC2283 (12-Bit), LTC2285 (14-Bit) 105Msps: LTC2282 (12-Bit), LTC2284 (14-Bit) 80Msps: LTC2294 (12-Bit), LTC2299 (14-Bit) 65Msps: LTC2293 (12-Bit), LTC2298 (14-Bit) 40Msps: LTC2292 (12-Bit), LTC2297 (14-Bit) n 64-Pin (9mm × 9mm) QFN Package
APPLICATIONS
n Wireless and Wired Broadband Communication n Imaging Systems n Spectral Analysis n Portable Instrumentation
LTC2285
Dual 14-Bit, 125Msps Low Power 3V ADC DESCRIPTION
The LTC®2285 is a 14-bit 125Msps, low power dual 3V A/D converter designed for digitizing high frequency, wide dynamic range signals. The LTC2285 is perfect for demanding imaging and communications applications with AC performance that includes 72.2dB SNR and 82dB SFDR for signals at the Nyquist frequency.
Typical DC specs include ±1.5LSB INL, ±0.6LSB DNL. The transition noise is a low 1.3LSBRMS.
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 performance at full speed for a wide range of clock duty cycles. A data ready output clock (CLKOUT) can be used to latch the output data.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
ANALOG INPUT A
+
INPUT S/H
–
14-BIT PIPELINED ADC CORE
CLK A CLK B
CLOCK/DUTY CYCLE CONTROL
CLOCK/DUTY CYCLE CONTROL
ANALOG INPUT B
+
INPUT S/H
–
14-BIT PIPELINED ADC CORE
OUTPUT DRIVERS
OVDD D13A
••• D0A OGND
OF
MUX CLKOUT
OUTPUT DRIVERS
OVDD D13B
••• D0B
OGND
2285 TA01
SNR (dBFS)
SNR vs Input Frequency, –1dB, 2V Range
75 74 73 72 71 70 69 68 67 66 65
0
50 100 150 200 250 300 350 INPUT FREQUENCY (MHz) 2285 TA01b
2285fb
1
LTC2285
ABSOLUTE MAXIMUM RATINGS
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
LTC2285C ................................................ 0°C to 70°C LTC2285I.............................................. –40°C to 85°C Storage Temperature Range................... –65°C to 150°C
PIN CONFIGURATION
TOP VIEW
AINA+ 1 AINA– 2 REFHA 3
REFHA 4
REFLA 5
REFLA 6
VDD 7
CLKA 8 CLKB 9
65
VDD 10 REFLB 11
REFLB 12
REFHB 13
REFHB 14 AINB– 15 AINB+ 16
64 GND 63 VDD 62 SENSEA 61 VCMA 60 MODE 59 SHDNA 58 OEA 57 OF 56 DA13 55 DA12 54 DA11 53 DA10 52 DA9 51 DA8 50 OGND 49 OVDD
48 DA7 47 DA6 46 DA5 45 DA4 44 DA3 43 DA2 42 DA1 41 DA0 40 CLKOUT 39 DB13 38 DB12 37 DB11 36 DB10 35 DB9 34 DB8 33 DB7
GND 17 VDD 18 SENSEB 19 VCMB 20 MUX 21 SHDNB 22 OEB 23 DB0 24 DB1 25 DB2 26 DB3 27 DB4 28 DB5 29 DB6 30 OGND 31 OVDD 32
UP PACKAGE 64-LEAD (9mm × 9mm) PLASTIC QFN
TJMAX = 150°C, θJA = 20°C/W EXPOSED PAD (PIN 65) IS GND AND MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LTC2285CUP#PBF
LTC2285CUP#TRPBF LTC2285UP
64-Lead (9mm × 9mm) Plastic QFN
0°C to 70°C
LTC2285IUP#PBF
LTC2285IUP#TRPBF
LTC2285UP
64-Lead (9mm × 9mm) Plastic QFN
–40°C to 85°C
LEAD BASED FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LTC2285CUP
LTC2285CUP#TR
LTC2285UP
64-Lead (9mm × 9mm) Plastic QFN
0°C to 70°C
LTC2285IUP
LTC2285IUP#TR
LTC2285UP
64-Lead (9mm × 9mm) Plastic QFN
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
CONVERTER CHARACTERISTICS The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Note 4)
PARAMETER
CONDITIONS
MIN TYP MAX
UNITS
Resolution (No Missing Codes)
● 14
Bits
Integral Linearity Error
Differential Analog Input (Note 5)
●
±1.5
LSB
Differential Linearity Error
Differential Analog Input
● –1 ±0.6 1.1
LSB
Offset Error
(Note 6)
● –12 ±2
12
mV
Gain Error
External Reference
● –2.5 ±0.5 2.5
%FS
Offset Drift
±1.