MAX3140 Maxim, MAX3140 Datasheet
MAX3140
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MAX3140 Summary of contents
Page 1
... Two control lines are included for hardware handshaking—one input and one output. The MAX3140 operates from a single +5V supply and typically consumes only 645µA with the receiver active. Hardware-invoked shutdown reduces supply current to only 20µA. The UART and RS-485/RS-422 functions can ...
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... GND) ......................................................Continuous CC + 0.3V) Continuous Power Dissipation (T CC 28-pin QSOP (derate 10.8mW/°C above +70°C)..........860mW + 0.3V) Operating Temperature Ranges CC MAX3140CEI .......................................................0°C to +70°C MAX3140EEI ....................................................-40°C to +85°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10sec) .............................+300° 1.8432MHz XTL A MIN = +25° ...
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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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... Driver Input to Output Driver Output Skew t DSKEW | | DPLH DPHL Driver Rise or Fall Time t DR Maximum Data Rate Driver Enable to Output High Driver Enable to Output Low Driver Disable Time from Low Driver Disable Time from High t Receiver Input to Output | Differential RPLH ...
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... Driver Input to Output t DPHL Driver Output Skew t DSKEW | DPLH DPHL Driver Rise or Fall Time t DR, Maximum Data Rate f MAX Driver Enable to Output High t DZH Driver Enable to Output Low t DZL Driver Disable Time from Low t DLZ Driver Disable Time from High t DHZ ...
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... OC Note 3: The SRL pin is internally biased to V Note 4: Maximum current level applies to peak current just prior to foldback-current limiting; minimum current level applies during current limiting. Note 5: The device is put into shutdown by bringing RE high and DE low. If the enable inputs are in this state for less than 50ns, the device is guaranteed not to enter shutdown ...
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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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... OUTPUT HIGH VOLTAGE (V) MAX3140-22 (5V/div) (2.5V/div) MAX3140-24 (5V/div) (2.5V/div) RS-485 RECEIVER PROPAGATION DELAY (SRL = GND (2V/div) RO (5V/div) 6 50ns/div RS-485 DRIVER PROPAGATION DELAY (SRL = OPEN) MAX3140- s/div RS-485 DRIVER PROPAGATION DELAY (SRL = GND) MAX3140- 50ns/div MAX3140-21 ...
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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 PLH ...
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... INPUT Figure 7. Receiver Propagation Delays Figure 9. Receiver Propagation Delay Test Circuit _______________Detailed Description The MAX3140 combines an SPI/QSPI/MICROWIRE- compatible UART (MAX3100) and an RS-485/RS-422 transceiver (MAX3089) in one package. The UART sup- ports data rates up to 230k baud for both standard UART bit streams as well as IrDA, and includes an 8-word receive FIFO ...
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... CPHA = 1) Figure 11. Compatible CPOL and CPHA Modes ______________________________________________________________________________________ UART The MAX3140 is compatible with SPI, QSPI (CPOL = 0, CPHA = 0), and MICROWIRE serial-interface standards (Figure 11). The MAX3140 has a unique full-duplex architecture that expects a 16-bit word for DIN and simultaneously produces a 16-bit word for DOUT regardless of which read/write register used ...
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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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... Parity-Enable Bit. Appends the Pt bit to the transmitted data when and sends the Pt bit as written. No parity bit is transmitted when With extra bit is expected to PE write 0 be received. This data is put into the Pr register when The MAX3140 does not calculate parity. PE read 0 Reads the value of the Parity-Enable bit ...
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... Reads the value of the TM bit (Table 7). read 0 Notice to High-Level Programmers The MAX3140 follows the SPI convention of providing a bidirectional data path for writes and reads. Whenever the data is written, data is also read back. This speeds operation over the SPI bus, as required, when operat- ing at high baud rates ...
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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 is optional, but ignore the 14 trailing zeros. Warning! The UART requires stable crystal oscillator operation before configuration (typically ~25ms after power-up) ...
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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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... Table 7 gives the details for each interrupt source. Figure 15 shows the function- al diagram for the interrupt sources and mask blocks. Two examples of setting up an IRQ for the MAX3140 are shown below. Example 1: Setting up only the transmit buffer-empty interrupt ...
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... This is the RA (RX-transition) bit in shutdown, and the FE (framing-error) bit in operating mode set if there has been a transition on RX since entering shutdown cleared when the MAX3140 exits shutdown. IRQ is asserted when RA is set and RAM = determined solely by the currently received data, and is not stored in FIFO. ...
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... With the receiver thresholds of the MAX3140, this results in a logic high with a 50mV mini- mum noise margin. Unlike previous fail-safe devices, the -50mV to -200mV threshold complies with the ± ...
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... This helps minimize parasitic capacitance and noise pickup in the oscillator, and reduces EMI. Minimize capacitive loading minimize supply current. The MAX3140’s X1 input can be driven directly by an external CMOS clock source. The trip level is approxi- mately equal to V mode TTL or non-CMOS clock source is used, AC- couple with a 10nF capacitor to X1 ...
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... This relieves the remote processor to handle more useful tasks. In 9-bit mode, the MAX3140 is set up with eight bits plus parity. The parity bit in all normal messages is clear, but is set in an address-type message. The MAX3140’s parity-interrupt mask generates an interrupt on high parity when enabled ...
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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 = GND. High- frequency harmonic components with large amplitudes are evident. Figure 18 shows the same signal for SRL = V , transmitting under the same conditions ...
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... CC 28 ______________________________________________________________________________________ network is shown in Figure 25. A typical full-duplex cir- cuit for the MAX3140 is shown in Figure 26, and a corre- sponding full-duplex network is shown in Figure 27. Since the MAX3140’s internal UART has IrDA capability, a standard IR transceiver (e.g., the MAX3120) can be used to provide IrDA communication (Figure 28). ...
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... MAX3140 Figure 25. Typical Half-Duplex RS-485 Network ______________________________________________________________________________________ V CC 10k V CC IRQ H/F DIN DOUT SHDN SCLK CTS CS RTS UART MAX3140 100k HALF-DUPLEX RS-485 I RXP RE* TXP SRL 120 ...
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... 120 MAX3140 Figure 27. Typical Full-Duplex RS-422 Network 30 ______________________________________________________________________________________ V CC 10k V IRQ CC DIN SHDN DOUT SCLK H/F CS UART CTS X1 RTS TX MAX3140 FULL-DUPLEX RS-422 I RXP RE* TXP SRL 120 D DI ...
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... True Fail-Safe RS-485/RS-422 Transceivers V CC 10k P SOFTWARE NON-IrDA *NOTE: TO SHUT DOWN THE RS-485 TRANSCEIVER, DRIVE RE SEPARATELY. Figure 28. Typical IR and RS-485 Operating Circuit ______________________________________________________________________________________ V +5V CC H/F IRQ UART DIN IN DOUT IrDA SCLK MODE CS MAX3140 V CC 100k RO R UART RTS RE* FLOAT SRL MAX3120 TX IrDA I ...
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... 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. Outline for a MAX3140 Software Driver 32 ______________________________________________________________________________________ The user must supply code for managing the transmit and receive queues, as well as the low-level hardware interface itself ...
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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 N.C. 14 QSOP ______________________________________________________________________________________ ___________________Chip Information TRANSISTOR COUNT: 7479 28 SHDN 27 IRQ SCLK 24 DOUT 23 DIN ...
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... True Fail-Safe RS-485/RS-422 Transceivers Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied ...