LMH0002MA Datasheet, PDF (5/13 Pages) Texas Instruments – LMH0002 SMPTE 292M / 259M Serial Digital Cable Driver

LMH0002
www.ti.com
SNLS215D – JANUARY 2006 – REVISED AUGUST 2008
APPLICATION INFORMATION
Device Operation
INPUT INTERFACING
The LMH0002 accepts either differential or single-ended input. The inputs are self-biased, allowing for simple AC
or DC coupling. DC-coupled inputs must be kept within the specified common-mode range. SDI and SDI are self-
biased at approximately 2.1V with V_CC = 3.3V. Figure 3 shows the differential input stage for SDI and SDI.
V_CC
SDI
SDI
V_CC
10 k:
5 k:
80:
10 k:
10 k:
Figure 3. Differential Input Stage for SDI and SDI.
OUTPUT INTERFACING
The LMH0002 uses current mode outputs. Single-ended output levels are 800 mV_P-P into 75Ω AC-coupled
coaxial cable (with R_REF = 750Ω). Output level is controlled by the value of the R_REF resistor connected between
the R_REF pin and V_CC.
The R_REF resistor should be placed as close as possible to the R_REF pin. In addition, the copper in the plane
layers below the R_REF network should be removed to minimize parasitic capacitance.
OUTPUT SLEW RATE CONTROL
The LMH0002 output rise and fall times are selectable for either SMPTE 259M or SMPTE 292M compliance via
the SD/HD pin. For slower rise and fall times, or SMPTE 259M compliance, SD/HD is set high. For faster rise
and fall times, or SMPTE 292M compliance, SD/HD is set low.
REPLACING THE GENNUM GS1528, GS1528A, and GS1578A
The LMH0002MA is form-fit-function compatible with the Gennum GS1528 and GS1528A. The LMH0002SQ is
form-fit-function compatible with the Gennum GS1578A.
Copyright © 2006–2008, Texas Instruments Incorporated
Product Folder Links: LMH0002
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