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SP3508 Series 20 Mbps 3.3 V 8 Channel Multiprotocol Transceiver - LQFP-100

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Mfr. Name: MaxLinear
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Product Specification Section
MaxLinear SP3508EF-L - Technical Attributes
Attributes Table
Data Rate: 20Mbps
Supply Voltage: 3.15V to 3.45V
Operating Temp Range: -40°C to +85°C
No of TX / RX: 8/8
Package Style:  LQFP-100
Mounting Method: Surface Mount
Features & Applications

The SP3508 is a monolithic device that supports eight (8) popular serial interface standards for Wide Area Network (WAN) connectivity. The SP3508 is fabricated using a low power BiCMOS process technology, and incorporates a regulated charge pump allowing +3.3V only operation. Exar's patented charge pump provides a regulated output of +5.5V, which will provide enough voltage for compliant operation in all modes. Eight (8) drivers and eight (8) receivers can be configured via software for any of the above interface modes at any time.

The SP3508 requires no additional external components for compliant operation for all of the eight (8) modes of operation other than six capacitors used for the internal charge pump. All necessary termination is integrated within the SP3508 and is switchable when V.35 drivers and V.35 receivers, or when V.receivers are used. The SP3508 provides the controls and transceiver availability for operating as either a DTE or DCE.

Additional features with the SP3508 include internal loopback that can be initiated in any of the operating modes by use of the LOOPBACK pin. While in loopback mode, receiver outputs are internally connected to driver inputs creating an internal signal path bypassing the serial communications controller for diagnostic testing.

The SP3508 also includes a latch enable pin with the driver and receiver address decoder. The internal V.or V.35 termination can be switched off using a control pin (TERM_OFF) for monitoring applications. All eight (8) drivers and receivers in the SP3508 include separate enable pins for added convenience. The SP3508 is ideal for WAN serial ports in networking equipment such as routers, access concentrators, network muxes, DSU/CSU's, networking test equipment, and other access devices.


  • Fast 20Mbps Differential Transmission Rates
  • Internal Transceiver Termination Resistors for V.11 & V.35
  • Interface Modes:
    • RS-232 (V.28)
    • EIA-530 (V.10 & V.11)
    • EIA-530A (V.10 & V.11)
    • X.21 (V.11)
    • RS-449/V.36
    • V.35 (V.35 & V.28)
  • Protocols are Software Selectable with 3-Bit Word
  • Eight (8) Drivers and Eight (8) Receivers
  • Termination Network Disable Option
  • Internal Line or Digital Loopback for Diagnostic Testing
  • Certified conformance to NET1/NET2 and TBR-1
  • TBR-2 by TUV Rheinland (TBR2/30451940.001/04)
  • Easy Flow-Through Pinout
  • +3.3V Only Operation
  • Individual Driver and Receiver Enable/Disable Controls
  • Operates in either DTE or DCE Mode
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