m21208 Mindspeed Technologies, m21208 Datasheet - Page 6

• Manufacturer Part Number: m21208
• Description: Sd And Hd/sd-sdi Digital Video Cable Drivers
• Manufacturer: Mindspeed Technologies

1.1
Through out this data sheet, physical pins will be denoted in BOLD print.
1.2
1.2.1
The output slew rate of the M21218 is selectable to conform with the different SD-SDI and HD-SDI specifications.
With SD/HD = Low, the high-definition (1485 Mbps) slew rate is typically 100 ps. The slew rate will vary depending
on the output matching network and BNC connector used.
With SD/HD = High, for standard definition (143 to 540 Mbps) applications, the slew rate is typically 600 ps, which
is compliant with SMPTE 259M and SMPTE 344M. The M21208 has no control over slew rate; this is set at the SD
requirement.
1.2.2
For SMPTE compliance, an external 750Ω ±1% resistor at RSET to AV
mV within a tolerance that is less than ±7%. The output amplitude can also be adjusted to range from 500 to 1600
mV using the following formula:
The actual swing is set as a function of the IC supply voltage and external termination voltage as shown in
Table
applications where a lossy matching or splitting networks are used, the M21208/M21218 offers additional gain for
up to 1600 mV output swings, so the output after the lossy network can be SMPTE compliant. For single-supply
3.3V operation, the swing range is compatible with the GS9068/GS9068A and GS1528/1528A.
Table 1-1.
212x8-DSH-001-B
* ±5% tolerance allowed for AV
1-1. For a 2.5V minimum termination voltage, the IC can be SMPTE compliant for all supply voltages. In
Output Swing = (600 / RSET) mVp–p
AV
2.5–3.3V
2.5–3.3V
DD
Output Swing vs. Supply and Termination Voltage
(V)
General Nomenclature
Features
HD-SDI and SD-SDI Slew-rate Selection
Output Amplitude Adjustment
DDTERM
1.0 Functional Description
.
AV
Mindspeed Proprietary and Confidential
Mindspeed Technologies
DDTERM
3.3V
5.0V
(V)*
[RSET in kΩ] (in mVpp, single-ended)
(Single-ended mVp–p)
Maximum Swing
®
1200 mV
1600 mV
DD
is recommended for a swing level of 800
(Single-ended mVp–p)
Minimum Swing
500 mV
500 mV
1