Linear Technology LTC1410 Datasheet

LTC1410

12-Bit, 1.25Msps Sampling

A/D Converter with Shutdown

EATU

F

■

1.25Msps Sample Rate

■

Power Dissipation: 160mW

■

71dB S/(N + D) and 82dB THD at Nyquist

■

No Pipeline Delay

■

Nap (7mW) and Sleep (10µW) Shutdown Modes

■

Operates with Internal 15ppm/°C Reference

RE

S

or External Reference

■

True Differential Inputs Reject Common Mode Noise

■

20MHz Full Power Bandwidth Sampling

■

±2.5V Bipolar Input Range

■

28-Pin SO Wide Package

U

O

PPLICATI

A

■

Telecommunications

■

Digital Signal Processing

■

Multiplexed Data Acquisition Systems

■

High Speed Data Acquisition

■

Spectrum Analysis

■

Imaging Systems

S

DUESCRIPTIO

The LTC®1410 is a 0.65µs, 1.25Msps, 12-bit sampling
A/D converter that draws only 160mW from ±5V supplies.
This easy-to-use device includes a high dynamic range
sample-and-hold, a precision reference and requires no
external components. Two digitally selectable power shut­down modes provide flexibility for low power systems.

The LTC1410’s full-scale input range is ±2.5V. Maximum
DC specifications include ±1LSB INL and ±1LSB DNL over
temperature. Outstanding AC performance includes 71dB
S/(N + D) and 82dB THD at the Nyquist input frequency of
625kHz.

The unique differential input sample-and-hold can acquire
single-ended or differential input signals up to its 20MHz
bandwidth. The 60dB common mode rejection allows
users to eliminate ground loops and common mode noise
by measuring signals differentially from the source.

The ADC has a µ P compatible, 12-bit parallel output port.
There is no pipeline delay in the conversion results. A
separate convert start input and a data ready signal (BUSY)
ease connections to FIFOs, DSPs and microprocessors.

10µF

+

U

O

A

PPLICATITYPICAL

Complete 1.25MHz, 12-Bit Sampling A/D Converter

DIFFERENTIAL

ANALOG INPUT

(–2.5V TO 2.5V)

2.50V

OUTPUT

V

REF

0.1µF

12-BIT

PARALLEL

BUS

10
11
12
13
14

1

+A

2

–A

3

V

4

REFCOMP

5

AGND

6

D11(MSB)

7

D10

8

D9

9

D8
D7
D6
D5
D4
DGND

REF

IN
IN

LTC1410

NAP/SLP

AV
DV

V

BUSY

CONVST

RD

SHDN

OGND

28

DD

27
26
25
24
23
22
21
20
19
18
17
16
15

–5V

10µF

µP CONTROL
LINES

1410 TA01

DD

SS

CS

D0
D1
D2
D3

10µF

0.1µF

, LTC and LT are registered trademarks of Linear Technology Corporation.

Effective Bits and Signal-to-(Noise + Distortion)

vs Input Frequency

5V

+

0.1µF

12 74

10

8

6

EFFECTIVE BITS

4

2

f

SAMPLE

0

1k

NYQUIST

= 1.25MHz

10k 100k 1M 10M

INPUT FREQUENCY (Hz)

LTC1410 • TA02

68
62
56

S/(N + D) (dB)

50

1

LTC1410

W

O

A

AVDD = DVDD = VDD (Notes 1, 2)

LUTEXI T

S

A

WUW

ARB

U
G

I

S

Supply Voltage (VDD)................................................ 6V

Negative Supply Voltage (VSS) ............................... –6V

Total Supply Voltage (VDD to VSS) .......................... 12V

Analog Input Voltage

(Note 3) .................................. VSS – 0.3V to VDD + 0.3V

Digital Input Voltage (Note 4) ............ VSS – 0.3V to 10V

Digital Output Voltage................... – 0.3V to VDD + 0.3V

Power Dissipation............................................. 500mW

Operating Temperature Range

LTC1410C .............................................. 0°C to 70°C

LTC1410I........................................... –40°C to 85°C

Storage Temperature Range................ –65°C to 150°C

Lead Temperature (Soldering, 10 sec)................. 300°C

PACKAGE

1

+A

IN

2

–A

IN

3

V

REF

AGND

D10

D9
D8
D7
D6
D5
D4

DGND

G PACKAGE

T

JMAX

T

4
5
6
7
8

9
10
11
12
13
14

= 110°C, θJA = 90°C/W (SW)

= 110°C, θJA = 95°C/W (G)

JMAX

REFCOMP

D11(MSB)

28-LEAD PLASTIC SSOP

/

O

RDER I FOR ATIO

TOP VIEW

28

AV

DD

27

DV

DD

26

V

SS

25

BUSY

24

CS

23

CONVST

22

RD

21

SHDN

20

NAP/SLP

19

OGND

18

D0

17

D1

16

D2

15

D3

SW PACKAGE

28-LEAD PLASTIC SO WIDE

PART NUMBER

LTC1410CG
LTC1410CSW
LTC1410IG
LTC1410ISW

WU

U

ORDER

Consult factory for Military grade parts.

U

U

IN

IN

ACQ
AP

VERTER

CCHARA TERIST

ICS

The ● denotes specifications which apply over the full operating

● ±8 LSB

= 0 ● ±15 ppm/°C

OUT(REF)

U
PUT

LOG

Analog Input Range (Note 9) 4.75V ≤ VDD ≤ 5.25V, –5.25V ≤ VSS ≤ –4.75V ● ±2.5 V
Analog Input Leakage Current CS = High ● ±1 µA
Analog Input Capacitance Between Conversions 17 pF

Sample-and-Hold Acquisition Time ● 50 100 ns
Sample-and-Hold Aperture Delay Time –1.5 ns
Sample-and-Hold Aperture Delay Time Jitter 5 ps

IA

The ● denotes specifications which apply over the full operating temperature range, otherwise

During Conversions 5 pF

RMS

CO

temperature range, otherwise specifications are at TA = 25°C. With Internal Reference (Notes 5, 6)

PARAMETER CONDITIONS MIN TYP MAX UNITS

Resolution (No Missing Codes) ● 12 Bits
Integral Linearity Error (Note 7) ● ±0.3 ±1 LSB
Differential Linearity Error ● ±0.3 ±1 LSB
Offset Error (Note 8) ±2 ±6 LSB

Full-Scale Error ±15 LSB
Full-Scale Tempco I

A

specifications are at TA = 25°C. (Note 5)

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V
I

IN

C

t
t
t

jitter

CMRR Analog Input Common Mode Rejection Ratio –2.5V < (–AIN = AIN) < 2.5V 60 dB

2

LTC1410

W

U

DY

A

ACCURAC Y

IC

otherwise specifications are at TA = 25°C. (Note 5)

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

S/(N + D) Signal-to-(Noise + Distortion) Ratio 100kHz Input Signal (Note 12) ● 70 72.5 dB

THD Total Harmonic Distortion 100kHz Input Signal, First 5 Harmonics –85 dB

Peak Harmonic or Spurious Noise 600kHz Input Signal ● –84 –74 dB

IMD Intermodulation Distortion f

Full Power Bandwidth 20 MHz
Full Linear Bandwidth (S/(N + D) ≥ 68dB) 2.5 MHz

U

UU

I TER AL REFERE CE CHARACTERISTICS

operating temperature range, otherwise specifications are at TA = 25°C. (Note 5)

PARAMETER CONDITIONS MIN TYP MAX UNITS

V

Output Voltage I

REF

V

Output Tempco I

REF

V

Line Regulation 4.75V ≤ VDD ≤ 5.25V 0.01 LSB/V

REF

V

Output Resistance I

REF

COMP Output Voltage I

U

DIGITAL I PUTS A D DIGITAL OUTPUTS

operating temperature range, otherwise specifications are at TA = 25°C. (Note 5)

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V

IH

V

IL

I

IN

C

IN

V

OH

V

OL

I

OZ

C

OZ

I

SOURCE

I

SINK

High Level Input Voltage V
Low Level Input Voltage VDD = 4.75V ● 0.8 V
Digital Input Current VIN = 0V to V
Digital Input Capacitance 5pF
High Level Output Voltage VDD = 4.75V

Low Level Output Voltage VDD = 4.75V

High-Z Output Leakage D11 to D0 V
High-Z Output Capacitance D11 to D0 CS High (Note 9 ) ● 15 pF
Output Source Current V
Output Sink Current V

POWER REQUIRE E TS

otherwise specifications are at TA = 25°C. (Note 5)

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V

DD

V

SS

I

DD

I

SS

Positive Supply Voltage (Notes 10, 11) 4.75 5.25 V
Negative Supply Voltage (Note 10) –4.75 –5.25 V
Positive Supply Current CS = RD = CONVST = 5V ● 12 16 mA

Nap Mode SHDN = 0V, NAP/SLP = 5V 1.5 2.3 mA
Sleep Mode SHDN = 0V, NAP/SLP = 0V 1 100 µA

Negative Supply Current CS = RD = CONVST = 5V ● 20 30 mA

Nap Mode SHDN = 0V, NAP/SLP = 5V 10 200 µA
Sleep Mode SHDN = 0V, NAP/SLP = 0V 1 100 µA

The ● denotes specifications which apply over the full operating temperature range,

600kHz Input Signal (Note 12)

600kHz Input Signal, First 5 Harmonics

= 29.37kHz, f

IN1

= 32.446kHz –84 dB

IN2

● 68 71.0 dB

● –82 –74 dB

The ● denotes specifications which apply over the full

= 0 2.480 2.500 2.520 V

OUT

= 0 ±15 ppm/°C

OUT

–5.25V ≤ V

OUT

= 0 4.06 V

OUT

≤ –4.75V 0.01 LSB/V

SS

 ≤ 0.1mA 2 kΩ

U

The ● denotes specifications which apply over the full

= 5.25V ● 2.4 V

DD

● ±10 µA

10 mA

W

U

DD

= –10µA 4.5 V

I

O

IO = –200µA ● 4.0 V

= 160µA 0.05 V

I

O

IO = 1.6mA ● 0.10 0.4 V

= 0V to VDD, CS High ● ±10 µA

OUT

= 0V –10 mA

OUT

= V

OUT

DD

The ● denotes specifications which apply over the full operating temperature range,

3

LTC1410

U

W

POWER REQUIRE E TS

otherwise specifications are at TA = 25°C. (Note 5)

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

P

D

W

Power Dissipation 160 230 mW

Nap Mode SHDN = 0V, NAP/SLP = 5V 7.5 12 mW
Sleep Mode SHDN = 0V, NAP/SLP = 0V 0.01 1 mW

U

TI I G CHARACTERISTICS

range, otherwise specifications are at TA = 25°C. (Note 5)

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

f

SAMPLE(MAX)

t

CONV

t

ACQ

t

ACQ+CONV

t

1

t

2

t

3

t

4

t

5

t

6

t

7

t

8

t

9

t

10

t

11

t

12

t

13

t

14

Maximum Sampling Frequency ● 1.25 MHz
Conversion Time ● 650 750 ns
Acquisition Time ● 50 100 ns
Throughput Time ● 800 ns

(Acquisition + Conversion)
CS to RD Setup Time (Notes 9, 10) ● 0ns
CS↓ to CONVST↓ Setup Time (Notes 9, 10) ● 10 ns
NAP/SLP↓ to SHDN ↓ Setup Time (Notes 9, 10) ● 10 ns
SHDN↑ to CONVST↓ Wake-Up Time (Note 10) 200 ns
CONVST Low Time (Notes 10, 11) ● 40 ns
CONVST to BUSY Delay CL = 25pF 10 ns

Data Ready Before BUSY↑ 20 35 ns

Delay Between Conversions (Note 10) ● 40 ns
Wait Time RD↓ After BUSY↑ (Note 10) ● –5 ns
Data Access Time After RD↓ CL = 25pF 15 25 ns

Bus Relinquish Time 820 ns

RD Low Time ● t
CONVST High Time ● 40 ns
Aperture Delay of Sample-and-Hold –1.5 ns

The ● denotes specifications which apply over the full operating temperature range,

The ● denotes specifications which apply over the full operating temperature

● 50 ns

● 15 ns

● 35 ns

C

= 100pF 20 35 ns

L

Commercial ● 25 ns
Industrial

● 50 ns

● 30 ns

10

ns

Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.

Note 2: All voltage values are with respect to ground with DGND, OGND
and AGND wired together unless otherwise noted.

Note 3: When these pin voltages are taken below V
will be clamped by internal diodes. This product can handle input currents
greater than 100mA below V

Note 4: When these pin voltages are taken below VSS, they will be clamped
by internal diodes. This product can handle input currents greater than
100mA below V

Note 5: V
otherwise specified.

Note 6: Linearity, offset and full-scale specifications apply for a single­ended +AIN input with –AIN grounded.

without latchup. These pins are not clamped to VDD.

SS

= 5V, VSS = –5V, f

DD

or above VDD without latchup.

SS

= 1.25MHz, tr = tf = 5ns unless

SAMPLE

or above VDD, they

SS

4

Note 7: 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 8: Bipolar offset is the offset voltage measured from –0.5LSB when
the output code flickers between 0000 0000 0000 and 1111 1111 1111.

Note 9: Guaranteed by design, not subject to test.
Note 10: Recommended operating conditions.
Note 11: The falling CONVST edge starts a conversion. If CONVST returns

high at a critical point during the conversion it can create small errors. For
best results ensure that CONVST returns high either within 425ns after the
start of the conversion or after BUSY rises.

Note 12: Signal-to-noise ratio (SNR) is measured at 100kHz and distortion
is measured at 600kHz. These results are used to calculate signal-to-noise
plus distortion (SINAD).

UW

TYPICAL PERFORMAN CE CHAR ACTERISTICS

LTC1410

S/(N + D) vs Input Frequency
and Amplitude

80
70
60
50
40
30
20
10

SIGNAL/(NOISE + DISTORTION) (dB)

VIN = 0dB

VIN = –20dB

VIN = –60dB

f

= 1.25MHz

SAMPLE

0

1k

10k 100k

INPUT FREQUENCY (Hz)

Spurious-Free Dynamic Range vs
Input Frequency

0
–10
–20
–30
–40
–50
–60
–70
–80
–90

SPURIOUS-FREE DYNAMIC RANGE (dB)

–100

10k

100k 1M 10M

INPUT FREQUENCY (Hz)

Integral Nonlinearity vs
Output Code

1.0

0.5

0

INL ERROR (LSB)

–0.5

–1.0

512 1536 2560

0

1024

2048

OUTPUT CODE

1M 10M

1410 G01

1410 G04

3072

3504

4096

1410 G07

Signal-to-Noise Ratio vs
Input Frequency

80
70
60
50
40
30
20

SIGNAL-TO-NOISE RATIO (dB)

10

0

1k

10k 100k

INPUT FREQUENCY (Hz)

1M 10M

1410 G02

Intermodulation Distortion Plot

0

–20

–40

–60

–80

AMPLITUDE (dB)

–100

–120

0

100

f

SAMPLE

= 88.19580078kHz

f

IN1

= 111.9995117kHz

f

IN2

200 300 400

FREQUENCY (kHz)

= 1.25MHz

500 600

1410 G05

Power Supply Feedthrough
vs Ripple Frequency

0

V

= 0.1V

RIPPLE

–20

–40

–60

V

–80

–100

–120

1k 100k 1M 10M

AMPLITUDE OF POWER SUPPLY FEEDTHROUGH (dB)

SS

V

DD

DGND

10k

RIPPLE FREQUENCY (Hz)

1410 G08

Distortion vs Input Frequency

0
–10
–20
–30
–40
–50
–60
–70
–80
–90

AMPLITUDE (dB BELOW THE FUNDAMENTAL)
–100

1k

2ND

10k 100k

INPUT FREQUENCY (Hz)

3RD

1M 10M

Differential Nonlinearity vs
Output Code

1.0

0.5

0

DNL ERROR (LSB)

–0.5

–1.0

512 1536 2560

0

1024

2048

OUTPUT CODE

3072

Input Common Mode Rejection
vs Input Frequency

80
70
60
50
40
30
20

COMMON MODE REJECTION (dB)

10

0

1k

10k 100k

INPUT FREQUENCY (Hz)

1M 10M

THD

3504

1410 G03

4096

1410 G06

1410 G09

5