ADIN1300BCPZ-R7 datasheet(37/79 Pages) AD

37 / 79 page

Data Sheet

ADIN1300

Rev. 0 | Page 37 of 79

COMPONENT RECOMMENDATIONS

Crystal

The typical connection for an external crystal (XTAL) is shown

in Figure 31. To ensure minimum current consumption and to

minimize stray capacitances, make connections between the

crystal, capacitors, and ground as close to the ADIN1300 as

possible. Consult individual crystal vendors for recommended

load information and crystal performance specifications.

25MHz

12pF

ADIN1300

Figure 31. Crystal Oscillator Connection

External Clock Input

If using a single-ended reference clock on XTAL_I/CLK_IN/

REF_CLK, leave XTAL_O open-circuit. This clock must be a

unipolar 2.5 V, 25 MHz sinewave or square wave signal. The

CLK_IN can also be driven by a 1.8 V square wave signal. When

using the RMII MAC interface, a single, 50 MHz reference clock

(REF_CLK) is required, which can be sourced from the MAC

or from an external source.

ADIN1300

Figure 32. External Clock Connection

Magnetics

Galvanic isolation is necessary between any two point-to-point

communication nodes in applications using the Ethernet protocol

to transmit/receive data to protect against faults and transients,

and achieve the best electromagnetic compatibility performance.

Magnetic coupling between the PHY and the RJ45 is the most

common way of achieving this isolation.

The magnetics can be discrete or integrated and there are

strengths and weaknesses to both. Choosing the discrete option

typically occupies more board space, but gives more freedom in

terms of layout, tends to be cheaper than integrated magnetics,

and offers better performance overall.

The integrated approach is a combined RJ45 connector jack with

the magnetics built in, which provides a more compact solution

due to fewer components and, in applications where space is at

a premium, condenses the required footprint, but tends to cost

more. Magnetics cores tend to be smaller and closer to each

other, which can compromise EMC performance, increase the

likelihood of crosstalk, and have impacts on performance by

increasing losses and introducing nonlinear distortion.

For optimum performance, a discrete transformer with

integrated common-mode choke is recommended for use with

the ADIN1300 PHY. The common-mode choke is important

because it attenuates any common-mode signals picked up by

the twisted pair cable from the environment, improving the

signal-to-noise ratio of the system. Transformers with an

autotransformer stage following the common-mode choke

provide additional attenuation of common-mode noise.

The ADIN1300 transmit drivers are voltage mode with on-chip

terminations. Therefore, connect each of the center tap pins on

the transformer on the ADIN1300 side separately to ground

through a 0.1 μF capacitor.

RJ451

MX–

MX+

MCT

75Ω

0.001µF

ADIN1300

PHY1

1ONLY ONE CHANNEL SHOWN

0.1µF

TRANSFORMER1

H5007NL

MDI_0_P

MDI_0_N

MDI_1_P

MDI_1_N

MDI_2_P

MDI_2_N

MDI_3_P

MDI_3_N

Figure 33. Isolation Using Discrete Magnetics, Only One Channel Shown,

Each Channel has Separate Components to Ground

The key considerations for the magnetics are outlined in

Table 29.

Table 29. Magnetics Selection

Parameter

Value

Conditions

Turns Ratio

1CT:1CT

Open-Circuit Inductance

350 μH

Min: 100 mV, 100 kHz, 8 mA

Insertion loss

−1 dB

Max: 0 MHz to 100 MHz

TRANSFORMER

MAGJACK

ADIN1300

RJ45

MDI_0_P

MDI_0_N

MDI_1_P

MDI_1_N

MDI_2_P

MDI_2_N

MDI_3_P

MDI_3_N

Figure 34. Magnetics Connection

POWER REQUIREMENTS

The ADIN1300 has the following three power supply domains

and requires a minimum of two supply sources, 0.9 V and 3.3 V:

•

DVDD_0P9 is the 0.9 V digital core power supply input.

•

AVDD_3P3 is the 3.3 V analog power supply input for the

PHY MDI interface, analog circuitry, crystal oscillator, DLL,

RESET_N, CLK25_REF generation, and LED circuitry.

ADIN1300BCPZ-R7 Folha de dados(PDF) 37 Page - Analog Devices

ADIN1300BCPZ-R7 Folha de dados(HTML) 37 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 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79

Folha de dados Download

Ligação URL