THS6182_07 Datasheet, PDF (1/35 Pages) Texas Instruments – LOW-POWER DISSIPATION ADSL LINE DRIVER

THS6182
www.ti.com
SLLS544G – SEPTEMBER 2002 – REVISED NOVEMBER 2004
LOW-POWER DISSIPATION ADSL LINE DRIVER
FEATURES
• Low-Power Dissipation Increases ADSL Line
Card Density
• Low THD of -88 dBc (100 Ω, 1 MHz)
• Low MTPR Driving +20 dBm on the Line
– -76 dBc With High Bias Setting
– -74 dBc With Low Bias Setting
• Wide Output Swing of 44 V_PP Differential Into
a 200-Ω Differential Load (V_CC = ±12 V)
• High Output Current of 600 mA (Typ)
• Wide Supply Voltage Range of ±5 V to ±15 V
• Pin Compatible with EL1503C and EL1508C
– Multiple Package Options
• Multiple Power Control Modes
– 11 mA/ch Full Bias Mode
– 7.5 mA/ch Mid Bias Mode
– 4 mA/ch Low Bias Mode
– 0.25 mA/ch Shutdown Mode
– I_ADJ Pin for User Controlled Bias Current
– Stable Operation Down to 1.8 mA/ch
• Low Noise for Increased Receiver Sensitivity
– 3.2 nV/√Hz Voltage Noise
– 1.5 pA/√Hz Noninverting Current Noise
– 10 pA/√Hz Inverting Current Noise
APPLICATIONS
• Ideal for Full Rate ADSL Applications
DESCRIPTION
The THS6182 is a current feedback differential line
driver ideal for full rate ADSL systems. Its extremely
low-power dissipation is ideal for ADSL systems that
must achieve high densities in ADSL central office
rack applications. The unique architecture of the
THS6182 allows the quiescent current to be much
lower than existing line drivers while still achieving
high linearity without the need for excess open loop
gain. Fixed multiple bias settings of the amplifiers
allow for enhanced power savings for line lengths
where the full performance of the amplifier is not
required. To allow for even more flexibility and power
savings, an I_ADJ pin is available to further lower the
bias currents while maintaining stable operation with
as little as 1.8 mA per channel. The wide output
swing of 44 Vpp differentially with ±12-V power
supplies allows for more dynamic headroom, keeping
distortion at a minimum. With a low 3.2 nV/√Hz
voltage noise coupled with a low 10 pA/√Hz inverting
current noise, the THS6182 increases the sensitivity
of the receive signals, allowing for better margins and
reach.
TYPICAL ADSL CO-LINE DRIVER CIRCUIT
USING ACTIVE IMPEDANCE
1 kΩ
CODEC
V_IN+
+12 V
−
8.68 Ω
+ _THS6182a
−12 V
1.33 kΩ
953 Ω 1.33 kΩ
CODEC
V_IN−
1 kΩ
+12V
−
8.68 Ω
+ _THS6182b
−12 V
20-dBm
Line
1:1.2 _Power
100 Ω
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PowerPAD is a trademark of Texas Instruments.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2002–2004, Texas Instruments Incorporated