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Details, datasheet, quote on part number:LMH6678LQ
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Datasheet text preview:
LMH6678 Low Power 2-Channel Central-Office xDSL Driver
December 2003
LMH6678 Low Power 2-Channel Central-Office xDSL Driver
General Description
The LMH6678 is a low power 2-channel differential output driver utilizing dual current feedback op amps with a fixed gain of AV = +5.4. The LMH6678 utilizes high integration with low power consumption to provide 580 mW at 19.8 dBm line output. The LMH6678 can also be put into a listen mode to maintain the termination for receive signals with 100 mW/Ch power dissipation. The LMH6678 has two separate 2-bit power control inputs compatible with 3.3V CMOS for each channel that enable independent control of line status. When the drivers for both channels are shut off, power consumption drops to only 6 mW. Thermal Shutdown function protects the IC from a shorted line fault or system over temperature. The LMH6678 is available in a 5mm x 4mm 24-lead LLP package.
Features
AVCC1 = AVCC2 = +12V, AVDD = DVDD = +3.3V, TA = 25°C, 2/3 Power Mode, Typical values unless specified. n Low power consumption -- Line power PLINE = 100 mW 580 mW/Ch -- No signal 185 mW/Ch -- Listen mode 100 mW/Ch -- Shutdown mode 3 mW/Ch n Power Supply +12V -- Analog (AVCC1, AVCC2) +3.3V -- Digital (DVDD, AVDD) n Output voltage swing @ RL = 31 -- Single ended 11.5 VPP -- Differential 23 VPP n Multi tone power ratio, f = 500 kHz 72 dB n Output current 580 mA n Thermal shutdown protection n 5mm x 4mm LLP package n Low thermal resistance 36°C/W (JA) n Small PCB footprint
Application
n Full rate ADSL, ADSL+, ADSL++ or G. Lite linecard n Remote DSLAMs
Block Diagram
20084037
© 2003 National Semiconductor Corporation
DS200840
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LMH6678
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. ESD Tolerance Human Body Model Machine Model VIN Differential Supply Voltages AVCC1 AGND or AVCC2 AGND DVDD DGND AVDD AGND DGND - AGND AVCC1 AVCC2 AVDD DVDD Voltage at Input Pin Analog Input AVCC1 (AVCC2) +0.8V, AGND -0.8V 2KV (Note 2) 200V (Note 8)
Digital Control Input Soldering Information Infrared or Convection (20 sec.) Storage Temperature Range Junction Temperature (Note 4)
DVDD +0.8V, DGND -0.8V 235°C -65°C to +150°C +150°C
± 3V
Operating Ratings (Note 1)
Supply Voltage AVCC1 to AGND AVCC2 to AGND DVDD to DGND AVDD to AGND Operating Temperature Range (Note 3), (Note 4) Package Thermal Resistance (JA) (Note 4) +12V ± 10% +12V ± 10% +3.3V ± 10% +3.3V ± 10% -40°C to +85°C 36°C/W
+13.2V +3.6V +3.6V
± 0.2V ± 0.2V ± 0.2V
Electrical Characteristics Unless otherwise specified, all limits guaranteed for TJ = 25°C, AVCC1 = AVCC2 = +12V, DVDD = AVDD = +3.3V. DGND = AGND = 0V, 2/3 Power Mode. See (Note 9).
Symbol Parameter Conditions Min (Note 6) Typ (Note 5) 50 700 -91 -98 -57 -71 72 57 6.04 14.4 6.1 20 6.16 28.4 Max (Note 6) Units
Dynamic Performance fCL SR HD2 HD3 MTPR VIN VIN RIN -3 dB BW Slew Rate (Note 7) 2nd Harmonic Distortion 3rd Harmonic Distortion Multi-Tone Power Ratio Differential Output Noise Input DC Voltage Input Resistance RL = 100 VIN_DIFF = ± 2.4V, RL = 100 fc = 1 MHz, VO = 2 VPP, RL = 31 fc = 200 kHz, VO = 2 VPP, RL = 31 fc = 1 MHz, VO = 2 VPP, RL = 31 fc = 200 kHz, VO = 2 VPP, RL = 31 f = 500 kHz 100 kHz to 10 MHz Common Mode Differential IDIFF = 10 µA from +IN to -IN VIN_DIFF = -1 to 1V, No Load f = 1 MHz, RL = 100 VIN_DIFF = ± 2.4V, No Load VIN_DIFF = ± 2.4V, RL = 31 VIN_DIFF = Output Voltage Swing Low VIN_DIFF = VIN_DIFF = VIN_DIFF = ISC Output Short Circuit Current 11.68 11.64 MHZ V/µs
Distortion and Noise Response dBc dBc dBc nV/ V k
Input Characteristics
Transfer Characteristics AV PSRR Xt VO Voltage Gain Power Supply Rejection Ratio Cross Talk Output Voltage Swing High +5.37 +5.40 -108 -95 11.85 11.75 11.74 0.15 0.25 0.31 +800 -800 0.36 0.39 mA V V +5.48 V/V dB
± 2.4V, IOUT = 580 mA ± 2.4V, No Load ± 2.4V, RL = 31 ± 2.4V, IOUT = 580 mA
Sourcing to Ground Sinking to Ground
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LMH6678
Electrical Characteristics Unless otherwise specified, all limits guaranteed for TJ = 25°C, AVCC1 = AVCC2 = +12V, DVDD = AVDD = +3.3V. DGND = AGND = 0V, 2/3 Power Mode. See (Note 9). (Continued)
Symbol IOUT Parameter Output Current Conditions VIN_DIFF = ± 2.4V Sourcing, RL = 20 Sinking, RL = 20 5.89 -40 B01 L H L H B01 L H L H B11 L L H H B11 L L H H B02 L H L H B02 L H L H B12 L L H H B12 L L H H .8 2.7
@ VIH = 3.3V @ VIH = 0V
Min (Note 6)
Typ (Note 5)
Max (Note 6)
Units mA
± 580
VOC VOS ICC
Output Common Mode Voltage Output Offset Voltage AVCC Quiescent Supply Current Full Power 2/3 Power 1/3 Power Shutdown
6 0
6.05 +40
V mV
Power Supply (Note 10), (Note 11) 28.6 18.6 9.2 33 22 12 0.2 11 7 3 16 12 7 0.05 1.1 3.3 0 -0.5 -0.5 2.43 0.02 0.02 2.75 +14.6 -2.7V 0.5 +0.5 +0.5 36.9 25.4 14.3 .95 19 15 10.3 .14 1.4 mA V V µA µA MHz V V mA mA
IDV
DVDD Quiescent Supply Current Full Power 2/3 Power 1/3 Power Shutdown
IAV VIH VIL IIH IIL fCP VHIGH VLOW
AVDD Quiescent Supply Current Input High Voltage Input Low Voltage Input High Current Input Low Current Charge Pump Frequency Charge Pump High Average Voltage Charge Pump Low Average Voltage
All Power Modes
Logic Inputs
Charge Pump Measure at DRIVE at Full Power Measure at CstoreH at Full Power Measure at CstoreL at Full Power
Note 1: Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics. Note 2: Human body model, 1.5k in series with 100pF. Note 3: Continuous short circuit operation at elevated ambient temperature can result in exceeding the maximum allowed junction temperature of 150° C. Note 4: The maximum power dissipation is a function of TJ(MAX), JA, and TA. The maximum allowable power dissipation at any ambient temperature is PD = (TJ(MAX) - TA)/JA. All numbers apply for packages soldered directly onto a PC board. Die attach pad is electrically connected to AGND. Note 5: Typical Values represent the most likely parametric norm. Note 6: All limits are guaranteed by testing or statistical analysis. Note 7: Slew rate is the slowest of the rising and falling slew rates. Note 8: Machine Model, 0 in series with 200 pF. Note 9: Electrical table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self heating where TJ > TA. Absolute maximum ratings indicate junction temperature limits beyond which the device may be permanently degraded, either mechanically or electrically. Note 10: Quiescent supply current specification apply for the condition of no input signal. See application section for information on power consumption as a function of output power, power control bit settings and external resistor RADJ. Note 11: "L" is VIL and "H" is VIH.
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