Document
W U
FEATURES
s Sample Rate: 2.5Msps s 80dB S/(N + D) and 90dB THD at 100kHz fIN s Single 5V Operation s No Pipeline Delay s Programmable Input Ranges s Low Power Dissipation: 195mW (Typ) s True Differential Inputs Reject Common Mode Noise s Out-of-Range Indicator s Internal or External Reference s Sleep (1µA) and Nap (2mA) Shutdown Modes s 36-Pin SSOP Package
U APPLICATIO S
s Telecommunications s High Speed Data Acquisition s Digital Signal Processing s Multiplexed Data Acquisition Systems s Spectrum Analysis s Imaging Systems
, LTC and LT are registered trademarks of Linear Technology Corporation.
LTC1411
Single Supply 14-Bit 2.5Msps ADC
DESCRIPTIO
The LTC ®1411 is a 2.5Msps sampling 14-bit A/D converter in a 36-pin SSOP package, which typically dissipates only 195mW from a single 5V supply. This device comes complete with a high bandwidth sample-andhold, a precision reference, programmable input ranges and an internally trimmed clock. The ADC can be powered down with either the Nap or Sleep mode for low power applications.
The LTC1411 converts either differential or single-ended inputs and presents data in 2’s complement format. Maximum DC specs include ±2LSB INL and 14-bit no missing code over temperature. Outstanding dynamic performance includes 80dB S/(N + D) and 90dB THD at 100kHz input frequency.
The LTC1411 has four programmable input ranges selected by two digital input pins, PGA0 and PGA1. This provides input spans of ±1.8V, ±1.27V, ±0.9V and ±0.64V. An out-of-the-range signal together with the D13 (MSB) will indicate whether a signal is over or under the ADC’s input range. A simple conversion start input and a data ready signal ease connections to FIFOs, DSPs and microprocessors.
BLOCK DIAGRA
1 AIN+ 2 AIN–
REFOUT 3
REFIN 4
2.5V BANDGAP REFERENCE
5k
5k 2k
REFCOM1 5
REFCOM2 6
X1.62/ X1.15
10 30 AVP DVP
+
14-BIT
– ADC
INTERNAL CLOCK
14
OUTPUT DRIVERS
CONTROL LOGIC
OVDD 29
OGND 28 D13 12
• • •
D0 25 BUSY
27 OTR
26
7, 8, 9
AGND
AVM SLP NAP PGA0 PGA1 CONVST DGND
11 36 35 34 33 32
31
1411 BD
S/(N + D) (dB)
EFFECTIVE BITS
S/(N + D) and Effective Bits vs Input Frequency
86 14
80 13
74 12
68 11
62 10
56
50
44
38
32
26
20
14 10
100
1000
10000
INPUT FREQUENCY (kHz)
1411 TA02
1411f
1
WU U
U WW W
LTC1411
ABSOLUTE AXI U RATI GS
AVP = DVP = OVDD = VDD (Notes 1, 2)
Supply Voltage (VDD) ................................................. 6V Analog Input Voltage (Note 3) ... – 0.3V to (VDD + 0.3V) Digital Input Voltage (Note 4) .................. – 0.3V to 10V Digital Output Voltage ............... – 0.3V to (VDD + 0.3V) Power Dissipation .............................................. 500mW Operating Temperature Range
LTC1411C ............................................... 0°C to 70°C LTC1411I ............................................ – 40°C to 85°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C
UW U PACKAGE/ORDER I FOR ATIO
AIN+ AIN–
REFOUT
1 2 3
REFIN 4
REFCOM1 5
REFCOM2 6
AGND1 7
AGND2 8
AGND3 9
AVP 10
AVM 11
D13 (MSB) 12
D12 13
D11 14
D10 15
D9 16
D8 17
D7 18
TOP VIEW
36 SLP 35 NAP 34 PGA0 33 PGA1 32 CONVST 31 DGND 30 DVP 29 OVDD 28 OGND 27 BUSY 26 OTR 25 D0 24 D1 23 D2 22 D3 21 D4 20 D5 19 D6
ORDER PART NUMBER
LTC1411CG LTC1411IG
G PACKAGE 36-LEAD PLASTIC SSOP
TJMAX = 125°C, θJA = 95°C/ W
Consult LTC Marketing for parts specified with wider operating temperature ranges.
CO VERTER CHARACTERISTICS The q denotes specifications which apply over the full operating
temperature range, otherwise specifications are TA = 25°C. (Notes 5, 6)
PARAMETER
CONDITIONS
MIN TYP MAX
Resolution (No Missing Codes) Integral Linearity Error Offset Error
Full-Scale Error Full-Scale Tempco
(Note 7) (Note 8)
External Reference = 2.5V IOUT(REF) = 0
q 14 q
q
±2
±16 ±24
± 60
±15
UNITS Bits LSB LSB LSB LSB
ppm/°C
DY A IC ACCURACY TA = 25°C (Note 5)
SYMBOL PARAMETER
CONDITIONS
S/(N + D) Signal-to-Noise Plus Distortion Ratio
100kHz Input Signal 500kHz Input Signal
THD Total Harmonic Distortion
100kHz Input Signal, Up to 5th Harmonic 500kHz Input Signal, Up to 5th Harmonic
Peak Harmonic or Spurious Noise
100kHz Input Signal 500kHz Input Signal
Full Linear Bandwidth Transition Noise
S/(N + D) ≥ 74dB
2
MIN TYP MAX UNITS 80.0 dB 77.5 dB – 90 dB – 82 dB 90 dB 82 dB 1.0 MHz 0.66 LSBRMS
1411f
LTC1411
UW UU
UU
A ALOG I PUT TA = 25°C (Note 5)
SYMBOL PARAMETER
CONDITIONS
VIN Analog Input Range (Note 9) Common Mode Input Range
(AIN+) – (AIN–), PGA0 = PGA1 = 5V (AIN+) – (AIN–), PGA0 = 5V, PGA1 = 0V (AIN+) – (AIN–), PGA0 = 0V, PGA1 = 5V (AIN+) – (AIN–), PGA0 = PGA1 = 0V AIN+ or AIN–
CIN Analog Input Capacitance
Between Conversions (Sample Mode) During Conversions (Hold Mode)
tACQ Sample-and-Hold Acquisition Time tAP Sample-and-Hold Aperture Delay Time
tjitter CMRR
Sample-and-Hold Aperture Delay Time Jitter Analog Input Common Mode Rejection Ratio 0V < (AIN– = AIN+) < VDD
Input Leak.