GS1672 datasheet(73/116 Pages) SEMTECH

73 / 116 page

GS1672 HD/SD-SDI Serializer with Complete SMPTE

Audio & Video Support

Data Sheet

53623 - 6

July 2011

73 of 116

The SDO and SDO pins of the device provide the serial digital output.

Compliance with all requirements defined in Section 4.12.1 through Section 4.12.4 is

guaranteed when measured across a 75Ω terminated load at the output of 1m of Belden

1694A cable, including the effects of the Gennum recommended ORL matching

network, BNC and coaxial cable connection, except where otherwise stated.

Figure 4-23 illustrates this requirement, which is in accordance with the measurement

methodology defined in SMPTE 292 and SMPTE 259M.

Figure 4-23: ORL Matching Network, BNC and Coaxial Cable Connection

4.12.1 Output Signal Interface Levels

The Serial Digital Output signals (SDO and SDO pins), of the device meet the amplitude

requirements as defined in SMPTE 424M for an unbalanced generator (single-ended).

The signal amplitude is controlled to better than +/-7% of the nominal level defined in

SMPTE 424M, when an external 750Ω 1% resistor is connected between the RSET pin of

the device and VCC.

The output signal amplitude can be reduced to less than 1/10th of the nominal

amplitude, defined above, by increasing the value of the resistor connected between the

RSET pin of the device and VCC.

These requirements are met across all ambient temperature and power supply

operating conditions described in the Electrical Characteristics on page 18.

The output amplitude of the GS1672 can be adjusted by changing the value of the RSET

resistor as shown in Table 4-29. For a 800mVp-p output a value of 750Ω is required. A

±1% SMT resistor should be used.

The RSET resistor is part of the high speed output circuit of the GS1672. The resistor

should be placed as close as possible to the RSET pin. In addition, an anti-pad should be

used underneath the resistor.

Table 4-28: Serial Digital Output - Serial Output Data Rate

Parameter

Symbol

Conditions

Min

Typ

Max

Units

Serial Output Data Rate

BRSDO

SMPTE 292 signal

−

1.485, 1.485/1.001

−

Gb/s

SMPTE 259M-C signal

−

270

−

Mb/s

DVB-ASI signal

−

270

−

Mb/s

DUT

GS1672

ORL

Matching

Network

BNC

75Ω

resistive

load

Measuring device

1m Belden 1694A75Ω

coaxialcable

GS1672 数据表(PDF) 73 Page - Semtech Corporation

GS1672 数据表(HTML) 73 Page - Semtech Corporation

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 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

数据表下载