®

®

ADS-119

3

+25°C

0 to +70°C

–55 to +125°C

DIGITAL OUTPUTS

MIN.

TYP.

MAX.

MIN.

TYP.

MAX.

MIN.

TYP.

MAX.

UNITS

Logic Levels

Logic "1"

+2.4

—

—

+2.4

—

—

+2.4

—

—

Volts

Logic "0"

—

—

+0.4

—

—

+0.4

—

—

+0.4

Volts

Logic Loading "1"

—

—

–4

—

—

–4

—

—

–4

mA

Logic Loading "0"

—

—

+4

—

—

+4

—

—

+4

mA

Output Coding

Offset Binary

POWER REQUIREMENTS

Power Supply Ranges ‘

+5V Supply

+4.75

+5.0

+5.25

+4.75

+5.0

+5.25

+4.9

+5.0

+5.25

Volts

–5V Supply

–4.75

–5.0

–5.25

–4.75

–5.0

–5.25

–4.9

–5.0

–5.25

Volts

Power Supply Current

+5V Supply

—

+200

+215

—

+200

+215

—

+200

+215

mA

–5V Supply

—

–180

–205

—

–180

–205

—

–180

–205

mA

Power Dissipation

—

1.8

2.1

—

1.8

2.1

—

1.8

2.1

Watts

Power Supply Rejection

—

—

±0.01

—

—

±0.01

—

—

±0.01

%FSR/%V

Figure 2. ADS-119 Timing Diagram

6.02

(SNR + Distortion) – 1.76 +

20 log

Full Scale Amplitude

Actual Input Amplitude

 Effective bits is equal to:

 This is the time required before the A/D output data is valid after the analog input

is back within the specified range.

Footnotes:

ΠAll power supplies must be on before applying a start convert pulse. All supplies

and the clock (START CONVERT) must be present during warmup periods. The

device must be continuously converting during this time. There is slight

degradation in performance when using ±12V supplies.

 See ordering information for availability of ±5V input range. Contact DATEL for

availability of other input voltage ranges.

Ž A 200ns wide start convert pulse is used for all production testing. Only the rising

edge of the start convert pulse is required for the device to operate

(edge-triggered).

TECHNICAL NOTES

1. Obtaining fully specified performance from the ADS-119

requires careful attention to pc-card layout and power

supply decoupling. The device's analog and digital ground

systems are connected to each other internally. For optimal

performance, tie all ground pins (14, 18, and 23) directly to

a large analog ground plane beneath the package.

Bypass all power supplies to ground with 4.7µF tantalum

capacitors in parallel with 0.1µF ceramic capacitors. Locate

the bypass capacitors as close to the unit as possible.

2. The ADS-119 achieves its specified accuracies without the

need for external calibration. If required, the device's small

initial offset and gain errors can be reduced to zero using

the adjustment circuitry shown in Figures 3 and 4. For

operation without adjustment, tie pin 17 to analog ground.

When using this circuitry, or any similar offset and gain-

calibration hardware, make adjustments following warmup.

To avoid interaction, always adjust offset before gain.

3. Applying a start convert pulse while a conversion is in

progress (EOC = logic "1") will initiate a new and inaccurate

conversion cycle.

4. Data is valid only for the time period (55ns, typical) shown in

Figure 2 even if the device is sampling at less than 10MHz.

START

CONVERT

DATA

INTERNAL S/H

N

N+1

DATA N-1 VALID

55ns typ.

50ns typ.

Acquisition Time

30ns min.

35ns typ.

37ns max.

Hold

65ns typ.

10ns typ.

DATA N VALID

INVALID DATA

45ns typ.

Scale is approximately 5ns per division.

INTERNAL EOC

15ns typ.

Conversion Time

DATA

VALID

40ns typ.

±5ns

35ns typ.

INVALID DATA

10ns typ.

INVALID DATA

Hold

40ns typ.

±5ns

60ns typ.

72ns min.

80ns typ.

83ns max.

20ns typ.