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REV. 0

ADP3402

Printed Circuit Board Layout Considerations

Use the following general guidelines when designing printed

circuit boards:

1. Split the battery connection to the VBAT and SIMBAT pins

of the ADP3402. Use separate traces for each connection

and locate the input capacitors as close to the pins as possible.

2. SIM input and output capacitors should be returned to the

SIMGND and kept as close as possible to the ADP3402 to

minimize noise. Traces to the SIM charge pump capacitor

should be kept as short as possible to minimize noise.

3. VCCA and VTCXO capacitors should be returned to

AGND.

4. VCC and VRTC capacitors should be returned to DGND.

5. Split the ground connections. Use separate traces or planes for

the analog, digital, and power grounds, and tie them together

at a single point, preferably close to the battery return.

OUTLINE DIMENSIONS

Dimensions shown in inches and (mm).

28-Lead Thin Shrink Small Outline (TSSOP)

(RU-28A)

0.244 (6.20)

0.236 (6.00)

28

15

14

1

0.386 (9.80)

0.378 (9.60)

0.325 (8.25)

0.313 (7.95)

PIN 1

SEATING

PLANE

0.006 (0.15)

0.002 (0.05)

0.0118 (0.30)

0.0075 (0.19)

0.0256

(0.65)

BSC

0.0433 (1.10)

MAX

0.0374 (0.95)

0.0335 (0.85)

0.0078 (0.200)

0.0035 (0.090)

0.030 (0.75)

0.020 (0.50)

8

0