T 3 OUT T 1 OUT T 2 OUT R 1 IN R 1 OUT T 2 IN T 1 IN GND V CC C 1 + C 1

Transcription

1 SP0/0/0/ V RS- Serial Transceivers FEATURES 0.μF External Charge Pump Capacitors kbps Data Rate Standard SOIC and SSOP Packaging Multiple Drivers and Receivers Single V Supply Operation.0μA Shutdown Mode Tri-State Receiver Outputs Meets all RS-F and V. Specifications Improved Driver Output Capacity for Mouse Applications /-kv ESD Protection* T OUT T OUT T OUT R IN R OUT T IN SP0 0 R IN R OUT SD EN T IN R OUT R IN C V V C C C DESCRIPTION The SP0, SP0, SP0 and SP are multi-channel RS- line transceivers in a variety of configurations to fit most communication needs. All models in this series feature low-power CMOS construction and Exar Patented (,0,) on-board charge pump circuitry to generate the /-V RS- voltage levels, using charge pump capacitors to save board space and reduce circuit cost. The SP0 and SP models feature a low-power shutdown mode which reduces power supply drain to µa. Model Number of RS- No. of RX active in Drivers Receivers Shutdown No. of External 0.μF Capacitors Shutdown WakeUp TTL Tri-State SP0 0 Yes No Yes SP0 0 No No No SP0 0 No No No SP 0 Yes No Yes Table. Mode Selection Table * All Driver Outputs and Receiver Inputs characterized per MIL-STD-C Method 0. Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00 Now Available in Lead Free Packaging Note: See page for other pinouts

2 These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below are not implied. Exposure to absolute maximum ratings conditions for extended periods of time may affect reliability. Supply Voltage (VCC)... V V... (Vcc-0.V) to.v V-...-.V Input Voltages Tin...-0.V to (Vcc 0.V) Rin.../-0V Output Voltages Tout...(V, 0.V) to (V-, -0.V Rout...-0.V to (Vcc 0.V) Short Circuit duration on Tout...Continuous Absolute Maximum Ratings Package Power Dissipation: -pin SSOP (derate.mw/ C above 0 C...00mW -pin WSOIC (derate.mw/ C above 0 C...00mW -pin SSOP (derate.mw/ C above 0 C...00mW -pin WSOIC (derate.mw/ C above 0 C...00mW Storage Temperature...- C to 0 C Lead Temperature (soldering, s) C Vcc = V, C to C = 0.μF, Tmin to Tmax, unless otherwise noted. ELECTRICAL CHARACTERISTICS PARAMETER TEST CONDITIONS MIN TYP MAX UNIT TTL INPUT Logic Threshold LOW, V IL TIN, EN, SD 0. Volts Logic Threshold HIGH, V IH TIN, EN, SD.0 Volts Logic Pull-Up Current TIN = 0V 00 μa Maximum Data Rate C L = 00pF, R L = kω kbps TTL OUTPUT Output Voltage LOW, V OL Iout =.ma: Vcc = V 0. Volts Output Voltage HIGH, V OH Iout = -.0mA. Volts Leakage Current RS- OUTPUT Output Voltage Swing EN = Vcc, 0V Vout Vcc Ta= C All Transmitter outputs loaded with k ohms to 0.0 /- μa /-.0 /- Volts Output Resistance Vcc = 0V, Vout = /-V 00 Ohms Output Short Circuit Current Infinite Duration /- ma RS- INPUT Voltage Range - Volts Voltage Threshold LOW Vcc = V, Ta= C 0.. Volts Voltage Threshold HIGH Vcc = V, Ta= C.. Volts Hysteresis Vcc = V Volts Resistance Ta= C, -V Vin V kω Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

3 ELECTRICAL CHARACTERISTICS Vcc =.0V, C to C = 0.μF, Tmin to Tmax, unless otherwise noted. Parameter TEST CONDITIONS MIN TYP MAX Unit DYNAMIC CHARACTERISTICS Receiver Propagation Delay RS- to TTL,. μs Instantaneous Slew Rate C L = 0pF, R L = -kω, Ta= C 0 V/ μs Transition Region Slew Rate C L = 00pF, R L = kω; Measured from V to -V or -V to V V/ μs Output Enable Time 00 ns Output Disable Time 0 ns POWER REQUIREMENTS Vcc (SP0)..00. Volts Vcc (SP0, SP0 and SP) Volts Vcc Power Supply Current No Load, Vcc = /-%,Ta= C ma Vcc Power Supply Current, Loaded All Transmitters RL = kω, Ta= C 0 ma Shutdown Supply Current Ta= C μa ENVIRONMENTAL AND MECHANICAL Operating Temperature, Commercial, _C 0 0 C Operating Temperature, Extended, _E -0 C Storage Temperature - 0 C Package _A Package _T Shrink (SSOP) small outline Wide (SOIC) small outline Transmitter Output R L = kω, C L =,000pF Transmitter Output R L = kω, C L =,00pF Receiver Output Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

4 Package PINOUTS T OUT T OUT T OUT R IN T OUT R IN T OUT R OUT T OUT R OUT R IN SD R IN T IN R OUT 0 EN R OUT 0 T OUT T IN C V C SP0 T IN R OUT R IN V C C T IN C V C SP0 T IN R OUT R IN V C C T OUT T OUT T OUT T OUT R IN T OUT R IN R IN R OUT T OUT R OUT R OUT R OUT R IN C V C SP0 0 T IN T IN R OUT R IN V C C R IN R OUT T IN R OUT R IN C V C SP 0 SHUTDOWN (SD) EN R IN R OUT T IN R OUT R IN V C C Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

5 FEATURES The SP0/0/0/ multi-channel RS- line transceivers provide a variety of configurations to fit most communication needs, especially those applications where /-V is not available. All models in this series feature lowpower CMOS construction and Exar's proprietary on-board charge pump circuitry to generate the /-V RS- voltage levels. The ability to use charge pump capacitors saves board space and reduces circuit cost. Different models within the series provide different driver/receiver combinations to match any application requirement. The SP0 and SP models feature a lowpower shutdown mode that reduces power supply drain to µa. The models in this series are available in -pin and -pin SO (wide) and SSOP (shrink) small outline packages. Devices can be specified for commercial (0ºC to 0ºC) or industrial/extended (-0ºC to ºC) operating temperatures. Theory Of Operation Charge pump The charge pump is an Exar patented design and uses a unique approach compared to older less-efficient designs. The charge pump still requires four external capacitors, but uses a four phase voltage shifting technique to attain symmetrical /-V power supplies. Figure a shows the waveform found on the positive side of capacitor C and Figure b shows the negative side of capacitor C. There is a free-running oscillator that controls the four phases of the voltage shifting. A description of each phase follows: Phase Vss charge storage - During this phase of the clock cycle, the positive side of capacitors C and C are initially charged to V. C is then switched to ground and the charge in C- is transferred to C-. Since C is connected to V, the voltage potential across capacitor C is now V. DESCRIPTION Phase Vss transfer: Phase two of the clock connects the negative terminal of C to the Vss storage capacitor and the positive terminal of C to ground, and transfers the generated -V to C. Simultaneously, the positive side of capacitor C is switched to V and the negative side is connected to ground. Phase Vdd charge storage: The third phase of the clock is identical to the first phase. The charge transferred in C produces -V in the negative terminal of C, which is applied to the negative side of C. Since C is at V, the voltage potential across C is V. Phase Vdd transfer: The fourth phase of the clock connects the negative terminal of C to ground, and transfers the generated V across C to C, the Vdd storage capacitor. Again, simultaneously with this, the positive side of capacitor C is switched to V and the negative side is connected to ground, and the cycle begins again. Since both V and V- are separately generated from Vcc; in a no-load condition V and V- will be symmetrical. Older charge pump approaches that generate V- from V will show a decrease in magnitude of V- compared to V due to the inherent inefficiencies in the design. The clock rate for the charge pump typically operates at greater than khz allowing the pump to run efficiently with small 0.uF capacitors with a V breakdown voltage rating. The SP0/0/0/ devices are made up of three basic circuit blocks - ) transmitter/ driver, ) receiver and ) charge pump. Each model within the series incorporates variations of these circuit to achieve the desired configuration and performance. Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

6 DESCRIPTION V a) C b) C -V Figure. Charge Pump Waveforms Transmitter/Driver The drivers are inverting transmitters, which accept either TTL or CMOS inputs and output the RS- output signals with an inverted sense relative to the input logic levels. Typically, the RS- output voltage swing is /-V with no load, and /-V minimum with full load. The transmitter outputs are protected against infinite short-circuits to ground without degradation in reliability. The drivers of the SP0 and SP can be tri-stated by using the SHUT- DOWN function. In the "power off" state, the output impedance will remain greater than 00 Ohms, again satisfying the RS- specifications. Should the input of the driver be left open, an internal 00kOhm pull-up resistor to Vcc forces the input high, thus committing the output to a low state. The slew rate of the transmitter output is internally limited to a maximum of 0V/µs in order to meet he EIA standards (EIA RS-D,,, Paragraph ). The transition of the loaded output from high to low also meets the monotonicity requirements of the standard. Receivers The receivers convert RS- input signals to inverted TTL signals. Since the input is usually from a transmission line where long cable length and system interference can degrade the signal, the inputs have a typical hysteresis margin of 00mV. This ensures that the receiver is virtually immune to noisy transmission lines. Should an input be left unconnected, an internal kohm pull-down resistor to ground will commit the output of the receiver to a HIGH state. Shutdown Mode The SP0 and SP feature a control input (SD) which will disable the device and reduce the power supply current to less than µa, making the parts ideal for battery-powered systems. In the "shutdown" mode the receivers and transmitters will both be tri-stated. The V output of the charge pump will discharge to Vcc and the V- output will discharge to ground. Enable (EN) The SP0 and SP feature an enable input which allows the receiver outputs to be either tri-stated or enabled. This can be especially useful when the receiver is tied directly to a microprocessor data bus. The enable pin is active high. = V V C C V V C C V DD Storage Capacitor V SS Storage Capacitor Figure, Charge pump - Phase Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

7 = V C C V C C V DD Storage Capacitor V SS Storage Capacitor Figure, Charge pump - Phase = V V C C V V C C V DD Storage Capacitor V SS Storage Capacitor Figure, Charge pump - Phase = V V C C C C V DD Storage Capacitor V SS Storage Capacitor Figure, Charge pump - Phase EIA STANDARDS The Electronic Industry Association (EIA) developed several standards of data transmission which are revised and updated in order to meet the requirements of the industry. In data processing, there are two basic means of communicating between systems and components. The RS- standard was first introduced in and, since that time, has become an industry standard. /-kv ESD PROTECTION The SP0/0/0/ are equipped with Exar proprietary ESD protection circuitry on all RS- inputs and outputs. This series has been characterized using MIL-STD-C Method 0. Human Body Model. Each device in the family can withstand up to /- kv of static discharge on all RS- inputs and outputs. All other pins of each device will maintain /-kv of ESD protection. The RS- is a relatively slow data exchange protocol, with a maximum baud rate of only 0kbaud, which can be transmitted over a maximum copper wire cable length of 0 feet. The SP0 through SP series of data communications interface products have been designed to meet both the EIA protocol standards, and the needs of the industry. Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

8 V INPUT.V.V V C C C C SP0 V V.V V V INPUT TYPICAL APPLICATION CIRCUITS.V.V V C C C C SP0 V V.V V TTL/CMOS INPUTS T IN T IN T T T T T OUT T OUT T OUT RS- OUTPUTS TTL/CMOS INPUTS T IN T IN T T T T T OUT T OUT T OUT RS- OUTPUTS TTL/CMOS OUTPUTS R OUT R R IN R OUT R R IN R OUT R R IN EN 0 SD RS- INPUTS TTL/CMOS OUTPUTS T IN R OUT R OUT R OUT 0 T R R R T OUT R IN R IN R IN RS- INPUTS V INPUT.V.V V C C C C SP0 V V.V V V INPUT.V.V V C C C C SP V V.V V TTL/CMOS INPUTS T IN T IN T T T T T OUT T OUT T OUT 0 RS- OUTPUTS TTL/CMOS INPUTS T IN T IN R OUT 0 R T T T T T OUT T OUT T OUT R IN RS- OUTPUTS TTL/CMOS OUTPUTS R OUT R OUT R OUT R OUT R R IN R R IN R R IN R R IN RS- INPUTS TTL/CMOS OUTPUTS R OUT R OUT R OUT R OUT EN R R IN R R IN R R IN R R IN SD RS- INPUTS Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

9 Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

10 Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

11 Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

12 Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

13 Part number Drivers Receivers Temperature range ORDERING INFORMATION Package Type SP0CA-L 0 to 0 0 C pin SSOP SP0CA-L/TR 0 to 0 0 C pin SSOP SP0CT-L 0 to 0 0 C pin WSOIC SP0CT-L/TR 0 to 0 0 C pin WSOIC SP0EA-L -0 to 0 C pin SSOP SP0EA-L/TR -0 to 0 C pin SSOP SP0ET-L -0 to 0 C pin WSOIC SP0ET-L/TR -0 to 0 C pin WSOIC SP0CT-L 0 to 0 0 C pin WSOIC SP0CT-L/TR 0 to 0 0 C pin WSOIC SP0ET-L -0 to 0 C pin WSOIC SP0ET-L/TR -0 to 0 C pin WSOIC SP0CA-L 0 to 0 0 C pin SSOP SP0CA-L/TR 0 to 0 0 C pin SSOP SP0CT-L 0 to 0 0 C pin WSOIC SP0CT-L/TR 0 to 0 0 C pin WSOIC SP0EA-L -0 to 0 C pin SSOP SP0EA-L/TR -0 to 0 C pin SSOP SP0ET-L -0 to 0 C pin WSOIC SP0ET-L/TR -0 to 0 C pin WSOIC SPCA-L 0 to 0 0 C pin SSOP SPCA-L/TR 0 to 0 0 C pin SSOP SPCT-L 0 to 0 0 C pin WSOIC SPCT-L/TR 0 to 0 0 C pin WSOIC SPEA-L -0 to 0 C pin SSOP SPEA-L/TR -0 to 0 C pin SSOP SPET-L -0 to 0 C pin WSOIC SPET-L/TR -0 to 0 C pin WSOIC Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00

14 Date Revision Description REVISION HISTORY --0 Rev B Original SP00/0/0/0/0// Sipex Data sheet Change revision to.0.0 and convert to Exar format. Remove EOL part numbers and associated verbiage. Update ordering information. June 0.0. SP0CA-L and SP0EA-L options removed per PDN -0 Notice EXAR Corporation reserves the right to make changes to any products contained in this publication in order to improve design, performance or reliability. EXAR Corporation assumes no representation that the circuits are free of patent infringement. Charts and schedules contained herein are only for illustration purposes and may vary depending upon a user's specific application. While the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized ; (b) the user assumes all such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances. Copyright 0 EXAR Corporation Datasheet June 0 Send your Serial Transceiver technical inquiry with technical details to: serialttechsupport@exar.com Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited. Exar Corporation 0 Kato Road, Fremont CA, ()-000 Fax ()-0 SP0, 0, 0, 00