Fan-Out And Trace Space Guidelines - Analog Devices ADRV9001 User Manual

UG-1828
Table 94. Impedance Table
Structure Coated
Layer Type Microstrip
1 Single N/A
ended
1 Single Yes
ended
1 Edge Yes
Coupled
Differential
1 Edge N/A
Coupled
Differential
3 Single N/A
ended
3 Edge N/A
Coupled
Differential
7 Edge N/A
Coupled
Differential
9 Edge N/A
Coupled
Differential
10 Edge N/A
Coupled
Differential
12 Edge Yes
Coupled
Differential
12 Single Yes
ended
12 Edge N/A
Coupled
Differential
12 Edge N/A
Coupled
Differential
N/A means not applicable.
1

FAN-OUT AND TRACE SPACE GUIDELINES

The ADRV9001 device family uses a 196-pin BGA 12 × 12 mm package. The pitch between the pins is 0.8 mm. This small pitch makes it
impractical to route all signals on a single layer. RF pins have been placed on the outer edges of the ADRV9001 package. This helps in
routing the critical signals without a fan-out via. Each digital signal is routed from the BGA pad using a 4.5 mil trace. The trace is
connected to the BGA using via-in-the-pad structure. The signals are buried in the inner layers of the board for routing to other parts of
the system.
Extra care needs to be taken to ensure that DEV_CLK signal is shielded from any potential source of noise. Recommended approach is to
use differential signalling for DEV_CLK clock. The data port interface signals when used in LVDS-SSI mode needs to be routed as 100 Ω
differential pairs. Figure 190 shows the fan out scheme of the ADRV9001 evaluation card. There are no traces being routed between BGA
pads on the top layer. As mentioned before ADRV9001 evaluation card uses via-in-the-pad technique. This routing approach can be
used for ADRV9001 if there are no issues with manufacturing capabilities.
Target Impedance
Impedance Tolerance
(Ω) (Ω)
1
50.00 ±5
50.00 ±5
100.00 ±10
100.00 ±10
50.00 ±5
100.00 ±10
100.00 ±10
100.00 ±10
100.00 ±10
100.00 ±10
50.00 ±5
100.00 ±10
100.00 ±10
Rev. PrA | Page 208 of 253
Edge
Target Coupled
Linewidth Pitch Reference
(mils) (mils) Layers
12.00 0.00 (2)
13.50 0.00 (2)
8.25 15.25 (2)
7.50 14.50 (2)
4.00 0.00 (2, 4)
3.75 10.75 (2, 4)
6.00 14.25 (6, 8)
6.25 15.00 (8, 11)
4.25 9.50 (11, 8)
8.00 15.25 (11)
12.00 0.00 (11)
7.50 14.50 (11)
8.25 15.50 (11)
Preliminary Technical Data
Modelled
Modelled
Impedance
Linewidth
(mils) (Ω)
13.00 50.87
12.00 50.42
8.00 100.43
9.00 100.55
4.25 49.53
3.75 100.86
6.00 99.75
6.00 100.68
4.50 100.23
8.00 100.80
12.00 50.31
9.00 100.55
8.25 99.64
Coplaner
Space
(mils)
9.50
10.75
9.15
9.25
17.88
12.02
12.02
12.14
11.89
10.00
10.00
9.25
10.02