ISL4238E Intersil Corporation, ISL4238E Datasheet
ISL4238E
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ISL4238E Summary of contents
Page 1
... TSSOP, and is nearly 20% thinner. The devices also include a noninverting always-active receiver for “wake-up” capability. The ISL4238E driver, 3 receiver device optimized for DCE applications with full hardware handshaking. It also includes a noninverting always-active receiver for RING INDICATOR monitoring ...
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... OUT T3 3 OUT OUT OUT ISL4238E, ISL4244E, ISL4245E TABLE 1. SUMMARY OF FEATURES NO. OF MONITOR Rx. QFN PKG OUTB DCE 5x5 1 DTE 5x5 1 DTE 5x5 1 Ordering Information PART NO. (BRAND) PKG. NO. ISL4244EIR-T L32.5x5 (4244EIR) ISL4245EIR L32.5x5 ...
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... Active high input to override automatic powerdown circuitry thereby keeping transmitters active. (FORCEOFF must be high). NOTE: 1. ISL4238E input pins incorporate positive feedback resistors. Once the input is driven to a valid logic level, the feedback resistor maintains that logic level until V is removed. Unused transmitter inputs may be left unconnected by the user. ...
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... Typical Operating Circuits NOTE 2 TTL/CMOS LOGIC LEVELS NOTE: 2. For V = 3.15V (3.3V -5%), use ISL4238E, ISL4244E, ISL4245E ISL4238E +3.3V + 0.1µ C1 0.1µ C2+ + 0.1µ C2 ...
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... Typical Operating Circuits TTL/CMOS LOGIC LEVELS CONTROL LOGIC 5 ISL4238E, ISL4244E, ISL4245E (Continued) ISL4244E, ISL4245E +3.3V + 0.1µ C1 0.1µ C2+ + 0.1µ C2 OUTB 18 R1 OUT R 1 5kΩ OUT R 5kΩ ...
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... Input Logic Threshold Low T , FORCEON, FORCEOFF IN Input Logic Threshold High T , FORCEON, FORCEOFF Transmitter Input Hysteresis Input Leakage Current T , FORCEON, FORCEOFF (ISL4238E, Note 4) IN Output Leakage Current FORCEOFF = GND Output Voltage Low I OUT Output Voltage High I OUT RECEIVER INPUTS Input Voltage Range ...
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... Electrical Specifications Test Conditions: ISL4238E V ISL424XE V PARAMETER ENHANCED AUTOMATIC POWERDOWN (FORCEON = GND, FORCEOFF = V Receiver Input Thresholds to See Figure 6 INVALID High Receiver Input Thresholds to See Figure 6 INVALID Low INVALID, Output Voltage Low I OUT INVALID, Output Voltage High I OUT Receiver Positive or Negative Threshold to INVALID High Delay ...
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... Human Body Model NOTES: 4. ISL4238E inputs utilize a positive feedback resistor. The input current is negligible when the input is at either supply rail “edge” is defined as a transition through the transmitter or receiver input thresholds. 6. Skew is measured at the receiver input switching points (1.4V). ...
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... Transmitter inputs on the ISL424XE float if left unconnected, and may cause I increases. Connect unused inputs to CC GND for the best performance. ISL4238E transmitter inputs incorporate an active positive feedback resistor that maintains the last input state in the absence of a forcing signal, so unused transmitter inputs may be left unconnected ...
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... FORCEOFF and FORCEON are driven high, or until a transition occurs on a receiver or transmitter input. Figure 5 illustrates a circuit for ensuring that the ISL4238E/4XE powers up as soon as FORCEOFF switches high. The rising edge of the Master Powerdown signal forces the device to power up, and the ISL4238E/4XE returns to enhanced automatic powerdown mode an RC time constant after this rising edge ...
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... DETECT EDGE R_IN DETECT FIGURE 7. ENHANCED AUTOMATIC POWERDOWN LOGIC on the state of the ISL4238E/4XE (see the next sections for methods of utilizing INVALID to power down the device). The time to recover from automatic powerdown mode is typically 100µs. Emulating Standard Automatic Powerdown If enhanced automatic powerdown isn’t desired, the user can ...
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... Figure 7). For immediate power up when the cable is reattached, connect FORCEON to FORCEOFF through a network similar to that shown in Figure 5. Capacitor Selection The ISL4238E charge pumps require 0.1µF, or greater, capacitors for 3.3V (5% tolerance) operation. For other supply voltages refer to Table 3 for capacitor values. Do not use values smaller than those listed in Table 3. ...
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... ISL4238E/44E loopback test result at 120kbps. For this test, all transmitters were simultaneously driving RS-232 loads in parallel with 1000pF, at 120kbps. Figure 14 shows the ISL4238E/44E loopback results for a single transmitter driving 1000pF and an RS-232 load at 250kbps. Figure 15 illustrates the ISL4245E loopback test result at 250kbps ...
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... FIGURE 16. ISL4245E LOOPBACK TEST AT 1Mbps (C = 250pF) L Interconnection with 3V and 5V Logic The ISL4238E/4XE directly interface with 5V CMOS and TTL logic families. Nevertheless, with the ISL4238E/4XE at 3.3V, and the logic supply at 5V, AC, HC, and CD4000 outputs can drive ISL4238E/4XE inputs, but ISL4238E/4XE outputs do not reach the minimum V IH families ...
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... Typical Performance Curves TRANSMITTER AT 250kbps OTHER TRANSMITTERS AT 30kbps 1000 2000 3000 LOAD CAPACITANCE (pF) FIGURE 17. ISL4238E TRANSMITTER OUTPUT VOLTAGE vs LOAD CAPACITANCE TRANSMITTER AT 1Mbps OTHER TRANSMITTERS AT 30kbps 1000 2000 3000 LOAD CAPACITANCE (pF) FIGURE 19 ...
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... LOAD CAPACITANCE (pF) FIGURE 21. ISL4244E SUPPLY CURRENT vs LOAD CAPACITANCE WHEN TRANSMITTING DATA 25 20 -SLEW 15 +SLEW 1000 2000 3000 LOAD CAPACITANCE (pF) FIGURE 23. ISL4238E/44E SLEW RATE vs LOAD CAPACITANCE 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 2.5 3.0 3.5 4.0 4.5 SUPPLY VOLTAGE (V) FIGURE 25. SUPPLY CURRENT vs SUPPLY VOLTAGE 16 ISL4238E, ISL4244E, ISL4245E 3.3V, T ...
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... However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 17 ISL4238E, ISL4244E, ISL4245E L32.5x5 32 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE (COMPLIANT TO JEDEC MO-220VHHD-2 ISSUE C ...