AD5674 datasheet(29/31 Pages) AD

29 / 31 page

Data Sheet

AD5673R/AD5677R

Rev. 0 | Page 29 of 31

SOLDER HEAT REFLOW

As with all IC reference voltage circuits, the reference value

experiences a shift induced by the soldering process. Analog

Devices, Inc., performs a reliability test called precondition to

mimic the effect of soldering a device to a board. The output

voltage specification in Table 2 and Table 3 includes the effect of

this reliability test.

Figure 63 shows the effect of solder heat reflow as measured

through the reliability test (precondition).

100

150

200

250

300

350

400

VREF (V)

POSTSOLDER HEAT REFLOW

PRESOLDER HEAT REFLOW

Figure 63. Solder Heat Reflow Reference Voltage Shift

LONG-TERM TEMPERATURE DRIFT

Figure 64 shows the change in VREF value after 1000 hours in the

life test at 150°C.

120

–40

–30

–20

–10

100

110

ELAPSED TIME (Hours)

100

200

300

400

500

600

700

800

900

1000

Figure 64. Reference Drift Through to 1000 Hours

THERMAL HYSTERESIS

Thermal hysteresis is the voltage difference induced on the

reference voltage by sweeping the temperature from ambient to

cold, to hot, and then back to ambient.

Thermal hysteresis data is shown in Figure 65. Thermal hysteresis

is measured by sweeping the temperature from ambient to −40°C,

then to +125°C, and returning to ambient. ∆VREF is then

measured between the two ambient measurements, as shown in

Figure 65 (first temperature sweep).

The same temperature sweep and measurements were

immediately repeated, and the results are shown in Figure 65

(subsequent temperature sweeps).

–130 –110

–90

–70

–50

–30

–10

DISTORTION (ppm)

FIRST TEMPERATURE SWEEP

SUBSEQUENT TEMPERATURE SWEEPS

Figure 65. Thermal Hysteresis

AD5674 Datasheet(PDF) 29 Page - Analog Devices

AD5674 Datasheet(HTML) 29 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

Datasheet Download

Link URL