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Date: 06/14/04

SP3508 Enhanced WAN Multi–Mode Serial Transceiver

© Copyright 2004 Sipex Corporation

FEATURES

■ 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)

✓ X.21 (V.11)

✓ EIA-530A (V.10 & V.11)

✓ RS-449/V.36

✓ V.35 (V.35 & V.28)

(V.10 & V.11)

■ 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

■ Adheres to NET1/NET2 and TBR-2 Compliancy

Requirements

■ Easy Flow-Through Pinout

■ +3.3V Only Operation

■ Individual Driver and Receiver Enable/Disable Controls

■ Operates in either DTE or DCE Mode

SP3508

Rugged 3.3V, 20Mbps, 8 Channel Multiprotocol Transceiver

with Programmable DCE/DTE and Termination Resistors

DESCRIPTION

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 Sipex regulated charge pump allowing

+3.3V only operation. Sipex'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.11 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.11 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.

Applicable U.S. Patents-5,306,954; and others patents pending

®

PRELIMINARY

APPLICATIONS

■ Router

■ Frame Relay

■ CSU

■ DSU

■ PBX

■ Secure Communication Terminals

Now Available in Lead Free Packaging

Refer to page 9 for pinout