MAX3140EEI+T Maxim Integrated Products, MAX3140EEI+T Datasheet
MAX3140EEI+T
Specifications of MAX3140EEI+T
Related parts for MAX3140EEI+T
MAX3140EEI+T Summary of contents
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... SPI/QSPI are trademarks of Motorola, Inc. MICROWIRE is a trademark of National Semiconductor Corp. Pin Configuration appears at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. o Integrated UART and RS-485/RS-422 Transceiver in a Single 28-Pin QSOP o SPI/MICROWIRE-Compatible Interface Saves µ ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers ABSOLUTE MAXIMUM RATINGS V to GND ..........................................................................+6V CC Input Voltage to GND (CS, SHDN, X1, CTS, RX, DIN, SCLK, RE, DE, H/F, SRL, TXP, RXP, Dl) .............-0. Output Voltage to ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers ELECTRICAL CHARACTERISTICS (continued GND, SHDN = +5V ±5 are measured with V = +5V, UART configured for 9600 baud ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers UART SWITCHING CHARACTERISTICS (V = +5V ±5 1.8432MHz XTL UART configured for 9600 baud +25°C.) (Note 1) A PARAMETER SYMBOL UART AC TIMING (Figure 1) CS ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers SWITCHING CHARACTERISTICS—SRL = Unconnected (V = +5V ±5 unless otherwise noted. Typical values are MIN MAX PARAMETER SYMBOL t Driver Input to ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers SWITCHING CHARACTERISTICS—SRL = +5V ±5 unless otherwise noted. Typical values are MIN MAX PARAMETER SYMBOL t Driver Input to ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers SWITCHING CHARACTERISTICS—SRL = GND (V = +5V ±5 unless otherwise noted. Typical values are MIN MAX PARAMETER SYMBOL t Driver Input to ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers (V = +5V +25°C, unless otherwise noted UART SUPPLY CURRENT vs. TEMPERATURE 1000 1.8432MHz CRYSTAL 900 TRANSMITTING AT 115.2 kbps 800 700 600 500 400 300 200 100 ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers (V = +5V +25°C, unless otherwise noted RS-485 RECEIVER OUTPUT LOW VOLTAGE vs. TEMPERATURE 0. 8mA RO 0.45 0.40 0.35 0.30 0.25 0.20 0.15 0.10 -60 ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers (V = +5V +25°C, unless otherwise noted OUTPUT CURRENT vs. RS-485 DRIVER OUTPUT LOW VOLTAGE 140 120 100 ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers PIN NAME FULL HALF DUPLEX DUPLEX UART Crystal Connection. Leave X2 unconnected for external clock. See the Crystals Oscillators, and Ceramic Resonators section. UART Crystal Connection. X1 also serves ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers PIN NAME FULL HALF DUPLEX DUPLEX RS-485 Receiver Phase. Connect RXP to GND or leave it unconnected for normal receiver 21 21 RXP phase/polarity. Connect RXP Positive ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Figure 1. Driver DC Test Load Figure 3. Driver Timing Test Circuit ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers 1.5V V OUTPUT PHL -1V INPUT Figure 7. Receiver Propagation Delays Figure 9. Receiver Propagation Delay Test Circuit _______________Detailed Description The MAX3140 combines ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers The universal asynchronous receiver transmitter (UART) interfaces the SPI/MICROWIRE-compatible syn- chronous serial data from a microprocessor (µP) to asynchronous, serial-data communication ports (RS- 485, IrDA). Figure 10 shows the MAX3140 functional diagram. ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers SCLK’s rising edge. DOUT (MISO) is read into the µP on SCLK’s rising edge. The first bit (bit 15) of DOUT transitions on CS’s falling edge, and bits 14–0 transition on SCLK’s ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Table 1. Bit Descriptions BIT BIT POR NAME TYPE STATE B0–B3 write 0000 Baud-Rate Divisor Select Bits. Sets the baud clock’s value (Table 6). B0–B3 read 0000 Baud-Rate Divisor Select Bits. Reads ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Table 1. Bit Descriptions (continued) BIT BIT POR NAME TYPE STATE Receiver-Activity/Framing-Error Bit. In shutdown mode, this is the RA bit. In normal operation, this is the FE bit. In shutdown mode, ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers WRITE CONFIGURATION Register Configure the UART by writing a 16-bit word to the WRITE CONFIGURATION register, which programs the baud rate, data-word length, parity enable, and enable of the 8-word receive FIFO. ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Bits 15 and 14 of the DOUT WRITE CONFIGURATION word (R and T) are sent out of the MAX3140 along with 14 trailing zeros. The use of the R and T bits ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers The device enters a test mode if bit 0 of the DIN config- uration word equals 1 when performing a READ CON- FIGURATION. In this mode the RTS ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Table 5. READ DATA Register Bit Assignment (D15, D14 = 0, 0) BIT DIN DOUT Notes: bit 15, 14: DIN ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Table 7. Interrupt Sources and Masks—Bit Descriptions BIT MASK MEANING NAME BIT WHEN SET PM Pr Received parity bit = Data available Transition on RX when in shutdown; framing ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Example 2: Setting up only the data-available (or data- being-read) interrupt. Send the 16-bit word below into DIN of the MAX3140 using the WRITE CONFIGURATION register. This 16-bit word configures the MAX3140 ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Receiver Input Filtering The receivers of the MAX3140, when operating in 115kbps or 500kbps mode, incorporate input filtering in addition to input hysteresis. This filtering enhances noise immunity with differential signals that ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers The MAX3140 supports a common multidrop communi- cation technique referred to as 9-bit mode. In this mode, the parity bit is set to indicate a message that contains a header with a ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers 20dB/div O 100kHz/div Figure 18. Driver Output Waveform and FFT Plot of MAX3140 with SRL = V , Transmitting a 20kHz Signal CC sis of a 20kHz signal transmitted with SRL = ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Typical Applications The MAX3140 is designed for bidirectional data com- munications on multipoint bus transmission lines. The RS-485 transceiver can be used in any RS-485 applica- tion due to its numerous features ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers + *NOTE: TO SHUT DOWN THE RS-485 TRANSCEIVER, DRIVE RE SEPARATELY. Figure 24. Typical Half-Duplex Operating Circuit 120Ω MAX3140 Figure 25. Typical ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers *NOTE: TO SHUT DOWN THE RS-485 TRANSCEIVER, DRIVE RE SEPARATELY WITH AN I μP. Figure 26. Typical Full-Duplex Operating Circuit A 120Ω 120Ω DI ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers V *NOTE: TO SHUT DOWN THE RS-485 TRANSCEIVER, DRIVE RE SEPARATELY. Figure 28. Typical IR and RS-485 Operating Circuit ______________________________________________________________________________________ CC 10k V +5V CC H/F IRQ UART DIN IN DOUT IrDA ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Listing C-language outline of an interrupt-driven software driver that interfaces to a MAX3140, providing an intermediate layer between the bit-manipulation sub- routine and the familiar PutChar/GetChar subroutines. Listing 1. ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Listing 1. Outline for a MAX3140 Software Driver (continued) ______________________________________________________________________________________ 33 ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Listing 1. Outline for a MAX3140 Software Driver (continued) 34 ______________________________________________________________________________________ ...
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SPI/MICROWIRE-Compatible UART with Integrated True Fail-Safe RS-485/RS-422 Transceivers Pin Configuration TOP VIEW + CTS 3 RTS MAX3140 TX 6 H/F 7 GND SRL 13 ...
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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 36 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2010 Maxim Integrated Products ...