LMH0346 3 Gbps HD/SD SDI Reclocker with Dual Differential Outputs General Description Features The LMH0346 3 Gbps HD/SD SDI Reclocker retimes serial digital video data conforming to the SMPTE 424M, SMPTE 292M, and SMPTE 259M (C) standards. The LMH0346 operates at serial data rates of 270 Mbps, 1.483 Gbps, 1.485 Gbps, 2.967 Gbps, and 2.97 Gbps. The LMH0346 supports DVB-ASI operation at 270 Mbps. The LMH0346 automatically detects the incoming data rate and adjusts itself to retime the incoming data to suppress accumulated jitter. The LMH0346 recovers the serial data-rate clock and optionally provides it as an output. The LMH0346 has two differential serial data outputs; the second output may be selected as a low-jitter, data-rate clock output. Controls and indicators are: serial clock or second serial data output select, manual rate select input, SD/HD rate indicator output, lock detect output, auto/manual data bypass and output mute. The serial data inputs, outputs, and serial clock outputs are differential LVPECL compatible. The CML serial data and serial clock outputs are suitable for driving 100Ω differentially terminated networks. The control logic inputs and outputs are LVCMOS compatible. The LMH0346 is powered from a single 3.3V supply. Power dissipation is typically 370 mW. The device is housed in a 20pin e-TSSOP package. ■ Supports SMPTE 424M, SMPTE 292M, and SMPTE 259M (C) serial digital video standards ■ Supports 270 Mbps, 1.483 Gbps, 1.485 Gbps, 2.967 ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Gbps, and 2.97 Gbps serial data rate operation Supports DVB-ASI at 270 Mbps Single 3.3V supply operation 370 mW typical power consumption Two differential, reclocked outputs Choice of second reclocked output or low-jitter, differential, data-rate clock output Single 27 MHz external crystal or reference clock input Manual rate select input SD/HD operating rate indicator output Lock Detect indicator output Output mute function for data and clock Auto/Manual reclocker bypass Differential LVPECL compatible serial data inputs and outputs LVCMOS control inputs and indicator outputs 20-Pin e-TSSOP package Industrial temperature range: -40°C to +85°C Footprint compatible with the LMH0046 Applications ■ SDTV/HDTV and 3 Gbps serial digital video interfaces for: — — — — Digital video routers and switchers Digital video processing and editing equipment DVB-ASI equipment Video standards and format converters Typical Application 20215001 © 2008 National Semiconductor Corporation 202150 www.national.com LMH0346 3 Gbps HD/SD SDI Reclocker with Dual Differential Outputs February 4, 2008 LMH0346 Block Diagram 20215003 Connection Diagram 20215002 The exposed die attach pad is the negative electrical terminal for this device. It must be connected to the negative power supply voltage. 20-Pin e-TSSOP Order Number LMH0346MH See NS Package Number MXA20A www.national.com 2 LMH0346 Pin Descriptions Pin Name Description 1 LF1 Loop Filter 2 LF2 Loop Filter 3 RATE 0 Data Rate Select Input 4 RATE 1 Data Rate Select Input 5 SDI Data Input True 6 SDI Data Input Complement 7 VCC Positive power supply input 8 BYPASS/AUTO BYPASS Bypass/Auto Bypass mode select 9 OUTPUT MUTE Data and Clock Output Mute Input (active low) 10 XTAL IN/EXT CLK Crystal or External Oscillator Input 11 XTAL OUT Crystal Oscillator Output 12 LOCK DETECT PLL Lock Detect Output (active high) 13 SCO/SDO2 Serial Clock or Serial Data Output 2 Complement 14 SCO/SDO2 Serial Clock or Serial Data Output 2 True 15 VCCO Positive power supply input (Output Driver) 16 SDO Data Output Complement 17 SDO Data Output True 18 VCCO Positive power supply input (Output Driver) 19 SD/HD Data Rate Range Output 20 SCO_EN Serial Clock or Serial Data 2 Output select (active high enables serial clock output) VEE Connect exposed DAP to negative power supply (ground) DAP 3 www.national.com LMH0346 Package Thermal Resistance, e-TSSOP Absolute Maximum Ratings (Note 1) θJA It is anticipated that this device will not be offered in a military qualified version. If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/Distributors for availability and specifications. Supply Voltage (VCC–VEE) Logic Supply Voltage (Vi) 4.0V VEE−0.15V to VCC +0.15V Logic Input Current (single input): Vi = VEE−0.15V Vi = VCC+0.15V Logic Output Voltage (Vo) Logic Output Source/Sink Current Serial Data Input Voltage (VSDI) Serial Data Output Sink Current (ISDO) 26.6°C/W θJC Storage Temp. Range Junction Temperature Lead Temperature (Soldering 4 Sec) ESD Rating (HBM) ESD Rating (MM) ESD Rating (CDM) 2.4°C/W −65°C to +150°C +125°C +260°C (Pb-free) 8 kV 400V 2 kV Recommended Operating Conditions −5 mA +5 mA VEE−0.15V to VCC +0.15V ±8 mA VCC to VCC−2.0V Supply Voltage (VCC–VEE) Logic Input Voltage Differential Serial Input Voltage Serial Data or Clock Output Sink Current (ISO) Operating Free Air Temperature (TA) 24 mA 3.3V ±5% VEE to VCC 800 mV ±10% 16 mA max. −40°C to +85°C DC Electrical Characteristics Over Supply Voltage and Operating Temperature ranges, unless otherwise specified. (Notes 2, 3) Symbol Parameter Conditions VIH Input Voltage High Level VIL Input Voltage Low Level IIH Input Current High Level VIH = VCC IIL Input Current Low Level VIL = VEE Reference Logic inputs VOH Output Voltage High Level IOH = −2 mA VOL Output Voltage Low Level IOL = +2 mA Logic outputs VSDID Serial Input Voltage, Differential (Note 8) VCMI Input Common Mode Voltage VSDID = 200 mV, (Note 8) VSDOD Serial Data Output Voltage, Differential 100Ω differential load SDO VSCOD Serial Clock Output Voltage, Differential 100Ω differential load, (Note 8) SCO VCMO Output Common Mode Voltage 100Ω differential load SDO, SCO Supply Current 2970 Mbps ICC www.national.com SDI Min Max Units 2 Typ VCC V VEE 0.8 V 1 65 µA −1 −25 µA 2 V VEE + 0.6 V 200 1600 mVP-P VEE+1.2 VCC−0.2 V 620 750 880 mVP-P 400 525 650 mVP-P VCC− VSDOD 111 4 V 126 mA Over Supply Voltage and Operating Temperature ranges, unless otherwise specified. (Note 3) Symbol Parameter Conditions BRSD Serial Data Rate SMPTE 259M, C BRSD Serial Data Rate BRSD Reference Min SDI, SDO Typ Max Units 270 Mbps SMPTE 292M 1483, 1485 Mbps Serial Data Rate SMPTE 424M 2967, 2970 Mbps TOLJIT Serial Input Jitter Tolerance 270 Mbps, (Notes 7, 8, 9) TOLJIT Serial Input Jitter Tolerance 270 Mbps, (Notes 7, 8, 10) TOLJIT Serial Input Jitter Tolerance TOLJIT SDI >6 UIP-P >0.6 UIP-P 1483 or 1485 Mbps, (Notes 7, 8, 9) >6 UIP-P Serial Input Jitter Tolerance 1483 or 1485 Mbps, (Notes 7, 8, 10) >0.6 UIP-P TOLJIT Serial Input Jitter Tolerance 2967 or 2970 Mbps, (Notes 7, 8, 9) >6 UIP-P TOLJIT Serial Input Jitter Tolerance 2967 or 2970 Mbps, (Notes 7, 8, 10) >0.6 UIP-P tJIT Serial Data Output Jitter 270 Mbps, (Notes 8, 11) tJIT Serial Data Output Jitter tJIT BWLOOP 0.01 0.03 UIP-P 1483 or 1485 Mbps, (Notes 8, 12) 0.03 0.04 UIP-P Serial Data Output Jitter 2967 or 2970 Mbps, (Notes 8, 13) 0.03 0.08 UIP-P Loop Bandwidth 270 Mbps, <0.1dB Peaking 275 kHz 1485 Mbps, <0.1dB Peaking 1.5 MHz 2970 Mbps, <0.1dB Peaking 2.75 MHz 270 MHz 1483 MHz 1485 MHz 2967 MHz 2970 MHz FCO Serial Clock Output Frequency 270 Mbps data rate FCO Serial Clock Output Frequency 1483 Mbps data rate FCO Serial Clock Output Frequency 1485 Mbps data rate FCO Serial Clock Output Frequency 2967 Mbps data rate FCO Serial Clock Output Frequency 2970 Mbps data rate tJIT Serial Clock Output Jitter SDO SCO 3 psRMS 40 60 % 45 55 % 15 ms 2 Serial Clock Output (Note 8) Alignment with respect to Data Interval SDO, SCO Serial Clock Output Duty Cycle (Note 8) SCO TACQ Acquisition Time (Notes 4, 6) tr, tf Input rise/fall time 10%–90% Logic inputs 5 1.5 ns www.national.com LMH0346 AC Electrical Characteristics LMH0346 Symbol Parameter Conditions Reference Min Typ SDI Max Units 1500 ps tr, tf Input rise/fall time 20%–80%, 270 Mbps, (Note 8) tr, tf Input rise/fall time 20%–80%, 1483 or 1485 Mbps, (Note 8) 270 ps tr, tf Input rise/fall time 20%–80%, 2967 or 2970 Mbps, (Note 8) 135 ps tr, tf Output rise/fall time 10%–90% Logic outputs 1.5 20%–80%, (Notes 5, 8) SDO, SCO 90 ns tr, tf Output rise/fall time FREF Reference Clock Frequency 27 MHz FTOL Reference Clock Frequency Tolerance ±50 ppm 130 ps Note 1: “Absolute Maximum Ratings” are those parameter values beyond which the life and operation of the device cannot be guaranteed. The stating herein of these maximums shall not be construed to imply that the device can or should be operated at or beyond these values. The table of “Electrical Characteristics” specifies acceptable device operating conditions. Note 2: Current flow into device pins is defined as positive. Current flow out of device pins is defined as negative. All voltages are referenced to VEE (equal to zero volts). Note 3: Typical values are stated for: VCC = +3.3V, TA = +25°C. Note 4: Spec is guaranteed by design. Note 5: RL = 100Ω differential. Note 6: Measured from first SDI transition until Lock Detect (LD) output goes high (true). Note 7: Peak-to-peak amplitude with sinusoidal modulation per SMPTE RP 184-1996 paragraph 4.1. The test data signal shall be color bars. Note 8: This parameter is guaranteed by characterization over voltage and temperature limits. Note 9: Refer to “A1” in Figure 1 of SMPTE RP 184-1996. Note 10: Refer to “A2” in Figure 1 of SMPTE RP 184-1996. Note 11: PRBS 210−1, input jitter = 31 psP-P Note 12: PRBS 210−1, input jitter = 24 psP-P Note 13: PRBS 210−1, input jitter = 22 psP-P www.national.com 6 The LMH0346 3 Gbps HD/SD SDI Reclocker is used in many types of digital video signal processing equipment. Supported serial digital video standards are SMPTE 259M (C), SMPTE 292M, and SMPTE 424M. Corresponding serial data rates are 270 Mbps, 1.483 Gbps, 1.485 Gbps, 2.967 Gbps, and 2.97 Gbps. DVB-ASI data at 270 Mbps may also be retimed. The LMH0346 retimes the serial data stream to suppress accumulated jitter. It provides two low-jitter, differential, serial data outputs. The second output may be selected to output either serial data or a low-jitter serial data-rate clock. Controls and indicators are: serial clock or second serial data output select, manual rate select input, SD/HD rate output, lock detect output, auto/manual data bypass and output mute. Serial data inputs are CML and LVPECL compatible. Serial data and clock outputs are differential CML and produce LVPECL compatible levels. The output buffer design can drive AC or DC-coupled, terminated 100Ω differential loads. The differential output level is 750 mVP-P ±10% into 100Ω AC or DC-coupled differential loads. Logic inputs and outputs are LVCMOS compatible. The device package is a 20-pin e-TSSOP which has an exposed die attach pad. The exposed die attach pad is electrically connected to device ground (VEE) and is the negative electrical terminal for the device. This terminal must be connected to the negative power supply or circuit ground. Serial Data Inputs, Serial Data and Clock Outputs SERIAL DATA INPUT AND OUTPUTS The differential serial data input, SDI, accepts serial digital video data at the rates specified in Table 1. The serial data 20215008 FIGURE 1. Equivalent SDI Input Circuit (SDI, SDI) 7 www.national.com LMH0346 input is differential LVPECL compatible. The input is intended to be DC interfaced to devices such as the LMH0344 adaptive cable equalizer. The input is not internally terminated or biased. The input may be AC-coupled if a suitable input bias voltage is provided. Figure 1 shows the equivalent input circuit for SDI and SDI. The LMH0346 has two, retimed, differential, serial data outputs, SDO and SCO/SDO2. These outputs provide low jitter, differential, retimed data to devices such as the LMH0302 cable driver. Output SCO/SDO2 is multiplexed and can provide either a second serial data output or a serial clock output. Figure 2 shows the equivalent output circuit for SDO, SDO, SCO/SDO2, and SCO/SDO2. The SCO_EN input controls the operating mode for the SCO/ SDO2 output. When the SCO_EN input is high the SCO/ SDO2 output provides a serial clock. When SCO_EN is low, the SCO/SDO2 output provides retimed serial data. Both differential serial data outputs, SDO and SCO/SDO2, are muted when the MUTE input is a logic low level. SCO/ SDO2 also mutes when the Bypass mode is activated when this output is operating as the serial clock output. When muted, SDO and SDO (or SDO2 and SDO2) will assume opposite differential output levels. The CML serial data outputs are differential LVPECL compatible. These outputs have internal 50Ω pull-ups and are suitable for driving AC or DC-coupled, 100Ω center-tapped, AC grounded or 100Ω un-centertapped, differentially terminated networks. Device Description LMH0346 20215009 FIGURE 2. Equivalent SDO Output Circuit (SDO, SDO, SCO/SDO2, SCO/SDO2) Auto-Rate Detect mode may be used for any supported data rate, including DVB-ASI. OPERATING SERIAL DATA RATES This device operates at serial data rates of 270 Mbps, 1483 Mbps, 1485 Mbps, 2967 Mbps, and 2970 Mbps. The device does not lock to harmonics of these rates. The device does not lock and automatically enters the reclocker bypass mode for the following data rates: 143 Mbps, 177 Mbps, 360 Mbps, and 540 Mbps. TABLE 1. Data Rate Select Input Codes Rate [1:0] Code SERIAL DATA CLOCK/SERIAL DATA 2 OUTPUT The Serial Data Clock/Serial Data 2 Output is controlled by the SCO_EN input and provides either a second retimed serial data output or a low jitter differential clock output appropriate to the serial data rate being processed. When operating as a serial clock output, the rising edge of the clock will be positioned within the corresponding serial data bit interval within 10% of the center of the data interval. Differential output SCO/SDO2 functions as the second serial data output when the SCO_EN input is a logic-low level. This output functions as the serial clock output when the SCO_EN input is a logic-high level. The SCO_EN input has an internal pull-down device and the default state of SCO_EN is low (serial data output 2 enabled). SCO/SDO2 is muted when the MUTE input is a logic low level. When the Bypass mode is activated and this output is functioning as a serial clock output, the output will also be muted. 00 Auto-Rate Detect mode 01 270 Mbps 10 1483/1485 Mbps, 2967/2970 Mbps Comments May be used to support DVBASI operation LOCK DETECT The Lock Detect (LD) output, when high, indicates that data is being received and the PLL is locked. LD may be connected to the MUTE input to mute the data and clock outputs when no data signal is being received. See Table 2. MUTE The MUTE input, when low, mutes the serial data and clock outputs. It may be connected to Lock Detect or externally driven to mute or un-mute the outputs. If MUTE is connected to LD, then the data and clock outputs are muted when the PLL is not locked. This function overrides the Bypass function: see Table 2. MUTE has an internal pull-up device to enable the output by default. Control Inputs and Indicator Outputs SERIAL DATA RATE SELECTOR The Serial Data Rate Selector (RATE [1:0]) permits the user to fix the operating serial data rate. The pins have internal pulldowns which maintain a logic-low input condition unless externally driven to a logic-high condition. This input also serves to place the device in a test mode. The codes shown in Table 1 select the desired operating serial data rate. The LMH0346 then enters either the Auto-Rate Detect mode or a single operating rate. Selecting the 270 Mbps rate mode may also be used when reclocking DVB-ASI data. DVB-ASI data is MPEG2 coded data that is transmitted in 8B10B coding. The device will reclock this data without harmonic locking. www.national.com Data Rate or Mode BYPASS/AUTO BYPASS The Bypass/Auto Bypass input, when high, forces the device to output the data without reclocking it. When this input is low, the device automatically bypasses the reclocking function when the device is in an unlocked condition or the detected data rate is a rate which the device does not support. See Table 2. BYPASS/AUTO BYPASS has an internal pull-down device. 8 LMH0346 TABLE 2. Control Functionality LOCK DETECT OUTPUT MUTE BYPASS/AUTO BYPASS DEVICE STATUS 0 1 0 PLL unlocked, reclocker bypassed 1 1 0 PLL locked to supported data rate, reclocker not bypassed X 0 X Outputs muted 0 LOCK DETECT X Outputs muted 1 LOCK DETECT 0 PLL locked to supported data rate, reclocker not bypassed 1 LOCK DETECT 1 PLL locked to supported data rate, reclocker bypassed X 1 1 Outputs not muted, reclocker bypassed is only valid when the PLL is locked and the Lock Detect output is high. When the PLL is not locked (the Lock Detect output is low), the SD/HD output defaults to HD (low). The SD/ HD output is undefined for a short time after lock detect assertion or deassertion due to a data rate change on SDI. See Figure 3 for a timing diagram showing the relationship between SDI, Lock Detect, and SD/HD. SD/HD The SD/HD output indicates whether the LMH0346 is processing SD or HD / 3 Gbps data rates. It may be used to control another device such as the LMH0302 cable driver. When this output is high it indicates that the data rate is 270 Mbps. When low, the indicated data rate is 1483, 1485, 2967, or 2970 Mbps. The SD/HD output is a registered function and 9 www.national.com LMH0346 20215005 FIGURE 3. SDI, Lock Detect, and SD/HD Timing SCO_EN Input SCO_EN enables the SCO/SDO2 differential output to function either as a serial clock or second serial data output. SCO/SDO2 functions as a serial clock when SCO_EN is high. This pin has an internal pull-down device. The default state (low) enables the SCO/SDO2 output as a second serial data output. www.national.com CRYSTAL OR EXTERNAL CLOCK REFERENCE The LMH0346 uses a 27 MHz crystal or external clock signal as a timing reference input. A 27 MHz parallel resonant crystal and load network may be connected to the XTAL IN/EXT CLK and XTAL OUT pins. Alternatively, a 27 MHz LVCMOS compatible clock signal may be input to XTAL IN/EXT CLK. Parameters for a suitable crystal are given in Table 3. 10 Parameter Value Value Shunt Capacitance 7 pF Frequency 27 MHz Series Resistance 40Ω max. Frequency Stability ±50 ppm @ recommended drive level Recommended Drive Level 100 µW Maximum Drive Level 500 µW Operating Mode Fundamental mode, Parallel Resonant Operating Temperature Range −10°C to +60°C Load Capacitance 20 pF 11 LMH0346 TABLE 3. Crystal Parameters Parameter www.national.com LMH0346 Application Information Figure 4 shows an application circuit for the LMH0346 along with the LMH0344 3 Gbps HD/SD SDI Adaptive Cable Equalizer and LMH0302 3 Gbps HD/SD SDI Cable Driver. 20215004 FIGURE 4. Application Circuit www.national.com 12 LMH0346 Physical Dimensions inches (millimeters) unless otherwise noted 20-Pin e-TSSOP Order Number LMH0346MH NS Package Number MXA20A 13 www.national.com LMH0346 3 Gbps HD/SD SDI Reclocker with Dual Differential Outputs Notes For more National Semiconductor product information and proven design tools, visit the following Web sites at: Products Design Support Amplifiers www.national.com/amplifiers WEBENCH www.national.com/webench Audio www.national.com/audio Analog University www.national.com/AU Clock Conditioners www.national.com/timing App Notes www.national.com/appnotes Data Converters www.national.com/adc Distributors www.national.com/contacts Displays www.national.com/displays Green Compliance www.national.com/quality/green Ethernet www.national.com/ethernet Packaging www.national.com/packaging Interface www.national.com/interface Quality and Reliability www.national.com/quality LVDS www.national.com/lvds Reference Designs www.national.com/refdesigns Power Management www.national.com/power Feedback www.national.com/feedback Switching Regulators www.national.com/switchers LDOs www.national.com/ldo LED Lighting www.national.com/led PowerWise www.national.com/powerwise Serial Digital Interface (SDI) www.national.com/sdi Temperature Sensors www.national.com/tempsensors Wireless (PLL/VCO) www.national.com/wireless THE CONTENTS OF THIS DOCUMENT ARE PROVIDED IN CONNECTION WITH NATIONAL SEMICONDUCTOR CORPORATION (“NATIONAL”) PRODUCTS. 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