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SC28L91

Selection guide

Datasheet

SC28L91
(Product Specification)
21-Oct-04, 43 pages, 268 kB

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SC28L91 - 3.3 V or 5.0 V Universal Asynchronous Receiver/Transmitter (UART)

General description
Features
Products/packages
Quality/reliability/chemical content
Pricing/ordering/availability
Samples
Discontinued information
Applications
Block diagrams/pinning
Design support
Parametrics/similar products
Print/email
Disclaimers
All information hereunder is subject to the subsequent disclaimers

General description

The SC28L91 is a new member of the IMPACT family of Serial Communications Controllers. It is a single channel UART operating at 3.3 V and 5.0 V VCC, 8 or 16 byte FIFOs and is quite compatible with software of the SC28L92 and previous UARTs offered by Philips. It is a new part that is similar to our previous one channel part but is vastly improved. The improvements being: 16 character receiver, 16 character transmit FIFOs, watch dog timer for the receiver, mode register 0 is added, extended baud rate, over all faster bus and data speeds, programmable receiver and transmitter interrupts and versatile I/O structure. (The previous one channel part, SCC2691, is NOT being discontinued.)

Pin programming will allow the device to operate with either the Motorola or Intel bus interface. Bit 3 of the MR0 register allows the device to operate in an 8-byte FIFO mode if strict compliance with an 8-byte FIFO structure is required.

The Philips Semiconductors SC28L91 Universal Asynchronous Receiver/Transmitter (UART) is a single-chip CMOS-LSI communications device that provides a full-duplex asynchronous receiver/transmitter channel in a single package. It interfaces directly with microprocessors and may be used in a polled or interrupt driven system with modem and DMA interface.

The operating mode and data format of the channel can be programmed independently. Additionally, the receiver and transmitter can select its operating speed as one of 28 fixed baud rates; a 16X clock derived from a programmable counter/timer, or an external 1X or 16X clock. The baud rate generator and counter/timer can operate directly from a crystal or from external clock inputs. The ability to independently program the operating speed of the receiver and transmitter make the UART particularly attractive for dual-speed channel applications such as clustered terminal systems.

The receiver and transmitter is buffered by 8 or 16 character FIFOs to minimize the potential of receiver overrun, transmitter underrun and to reduce interrupt overhead in interrupt driven systems. In addition, a flow control capability is provided via RTS/CTS signaling to disable a remote transmitter when the receiver buffer is full.

DMA interface is and other general purpose signals are provided on the SC28L91 via a multipurpose 7-bit input port and a multipurpose 8-bit output port. These can be used as general-purpose ports or can be assigned specific functions (such as clock inputs or status/interrupt outputs, FIFO conditions) under program control.

The SC28L91 is available in two package versions: a 44-pin PLCC and 44-pin plastic quad flat pack (PQFP).

Features

  • Member of IMPACT family: 3.3 to 5.0 volt , -40 Cel to +85 Cel and 68K for 80xxx bus interface for all devices.
  • A full-duplex independent asynchronous receiver/transmitter
  • 16 character FIFOs for each receiver and transmitter
  • Pin programming selects 68K or 80xxx-bus interface
  • Programmable data format
    • 5 to 8 data bits plus parity
    • Odd, even, no parity or force parity
    • - 1, 1.5 or 2 stop bits programmable in 1/16-bit increments
  • 16-bit programmable Counter/Timer
  • Programmable baud rate for each receiver and transmitter selectable from:
    • 28 fixed rates: 50 to 230.4 k baud
    • Other baud rates to 1 MHz at 16X
    • Programmable user-defined rates derived from a programmable counter/timer
    • External 1X or 16X clock
  • Parity, framing, and overrun error detection
  • False start bit detection
  • Line break detection and generation
  • Programmable channel mode
    • Normal (full-duplex)
    • Automatic echo
    • Local loop back
    • Remote loop back
    • Multi-drop mode (also called 'wake-up' or '9-bit')
  • Multi-function 7-bit input port (includes IACKN)
    • Can serve as clock or control inputs
    • Change of state detection on four inputs
    • Inputs have typically >100 kOhm pull-up resistors
    • Change of state detectors for modem control
  • Multi-function 8-bit output port
    • Individual bit set/reset capability
    • Outputs can be programmed to be status/interrupt signals
    • FIFO status for DMA interface
  • Versatile interrupt system
    • Single interrupt output with eight maskable interrupting conditions
    • Output port can be configured to provide a total of up to six separate interrupt outputs that may be wire ORed.
    • Each FIFO can be programmed for four different interrupt levels
    • Watchdog timer for the receiver
  • Maximum data transfer rates:
  • 1X - 1 Mbit/s, 16X - 1 Mbit/s
  • Automatic wake-up mode for multi-drop applications
  • Start-end break interrupt/status with mid-character break detect.
  • On-chip crystal oscillator
  • Power-down mode
  • Receiver time-out mode
  • Single +3.3 V or +5 V power supply

Products/packages

Type numberOrderable part numberOrdering code (12NC)Product statusPackagePackingMarkingECCN
SC28L91A1ASC28L91A1A,5129352 674 18512Volume productionSOT187-2
(PLCC44)
Tube Dry PackStandard Marking
SC28L91A1ASC28L91A1A,5189352 674 18518Volume productionSOT187-2
(PLCC44)
Reel Dry Pack, SMD, 13"Standard Marking
SC28L91A1ASC28L91A1A,5299352 674 18529Volume productionSOT187-2
(PLCC44)
SC28L91A1BSC28L91A1B,5289352 674 19528Volume productionSOT307-2
(QFP44)
Reel Dry Pack, SMD, 13",TurnedStandard Marking
SC28L91A1BSC28L91A1B,5519352 674 19551Volume productionSOT307-2
(QFP44)
Tray Dry Pack, Bakeable, SingleStandard Marking
SC28L91A1BSC28L91A1B,5579352 674 19557Volume productionSOT307-2
(QFP44)
Tray Dry Pack, Bakeable, MultipleStandard Marking

Quality/reliability/chemical content

Type numberOrderable part numberChemical contentRoHSLeadfree Conversion dateRHFIRF (FIT)MTBF (hours)MSL
SC28L91A1ASC28L91A1A,512SC28L91A1A
week 8, 2005
SC28L91A1ASC28L91A1A,518SC28L91A1A
week 8, 2005
SC28L91A1ASC28L91A1A,529SC28L91A1A
week 8, 2005
SC28L91A1BSC28L91A1B,528SC28L91A1B
week 13, 2005
SC28L91A1BSC28L91A1B,551SC28L91A1B
week 13, 2005
SC28L91A1BSC28L91A1B,557SC28L91A1B
week 13, 2005

Quality and reliability disclaimer

Pricing/ordering/availability

Type numberOrdering code(12NC)Orderable part numberIndicative price/unit($)RegionDistributorIn stockOrder quantityInventory dateBuy onlineSamples
SC28L91A1A9352 674 18512  SC28L91A1A,512  5.2000NAFUTURE ELECTRONICS10 11/19/2009Buy onlineOrder samples
SC28L91A1A9352 674 18518  SC28L91A1A,518  5.2000      not available
SC28L91A1A9352 674 18529  SC28L91A1A,529  5.2000NADIGI-KEY CORPORATION357 11/20/2009Buy onlinenot available
SC28L91A1B9352 674 19528  SC28L91A1B,528  11.0200NAARROW ELECTRONICS475 11/19/2009Buy onlinenot available
    NAAVNET ELECTRONICS MARKETING386 11/19/2009Buy online 
SC28L91A1B9352 674 19551  SC28L91A1B,551  11.0200NAARROW ELECTRONICS475 11/19/2009Buy onlinenot available
    NAAVNET ELECTRONICS MARKETING386 11/19/2009Buy online 
    NADIGI-KEY CORPORATION79 11/20/2009Buy online 
    NAAVNET ELECTRONICS MARKETING128 11/19/2009Buy online 
SC28L91A1B9352 674 19557  SC28L91A1B,557  11.0200NAMOUSER ELECTRONICS20 11/20/2009Buy onlineOrder samples
    NAARROW ELECTRONICS475 11/19/2009Buy online 
    NAMOUSER ELECTRONICS20 11/20/2009Buy online 
    NAAVNET ELECTRONICS MARKETING772 11/19/2009Buy online