EY1603 Datasheet, PDF (9/10 Pages) Altera Corporation – 40V, Low Quiescent Current, 150mA Linear Regulator

Page 9
To calculate the maximum ambient operating temperature, use the junction-to-ambient thermal resistance (_JA) as
shown in Equation 3:
T_{JMAX} = P_{DMAX} x _JA + T_A
(EQ. 3)
Board Layout Recommendations
A good PCB layout is important to achieve expected performance. Consideration should be taken when placing the
components and routing the trace to minimize the ground impedance and keep the parasitic inductance low. The
input and output capacitors should have a good ground connection and be placed as close to the IC as possible. The
feedback trace in the adjustable version should be away from other noisy traces.
The 14 Ld HTSSOP package uses the copper area on the PCB as a heat-sink. The EPAD of this package must be
soldered to the copper plane (GND plane) for effective heat dissipation. Figure 12 shows a curve for _JA of the package
for different copper area sizes.
38
36
34
32
30
28
26
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160
EPAD-MOUNT COPPER LAND AREA ON PCB, mm²
FIGURE 12. _JA vs EPAD-MOUNT COPPER LAND AREA ON PCB
Document Revision History
The table lists the revision history for this document.
Date
February 2014
Version
1.0 Initial release.
Changes
February 2014 Altera Corporation
09619
EY1603 40V, Low Quiescent Current, 150mA Linear Regulator
March 14, 2014
Rev A