LTC RO R 2 RE 3 DE 1 RO 2 3 DE 4 DI 2000 FEET OF TWISTED-PAIR WIRE 7 RECEIVER INPUT DI. 4.7nF RO

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1 µ µ µ LTC1487 µ µ TYPICL PPLICTI UO LTC1487 LTC E D 6 12Ω 2 FEET OF TWISTED-PI WIE 33Ω 7 12Ω 6 D 1 2 E 3 4 ECEIVE INPUT 4.7nF EQUIVLENT LOD OF 256 LTC1487 TNSCEIVES LTC1487 T1 LTC1487 T2 5-49

2 SOLUTE XI U TI GS W W W (Note 1) Supply Voltage ( )... 12V Control Input Voltage....5V to +.5V Driver Input Voltage....5V to +.5V Driver Output Voltage... ±14V eceiver Input Voltage... ±14V eceiver Output Voltage....5V to +.5V Operating Temperature ange... C T 7 C Lead Temperature (Soldering, 1 sec)... 3 C U PCKGE/O I FO E N8 PCKGE 8-LED PP TOP VIEW D GND S8 PCKGE 8-LED PLSTIC SO W U TIO O PT NUME LTC1487CN8 LTC1487CS8 LTC1487IN8 LTC1487IS8 U S8 PT MKING T JMX = 125 C, θ J = 13 C/ W (N8) T JMX = 125 C, θ J = 15 C/ W (S8) I Consult factory for Military grade parts. ELECTICL CHCTEISTICS C T 7 C, = 5V (Notes 2, 3) unless otherwise noted. SYMOL PMETE CONTIONS MIN TYP MX UNITS V OD1 Differential Driver Output Voltage (Unloaded) I O = 5 V V OD2 Differential Driver Output Voltage (with Load) = 5Ω (S422) 2. V = 27Ω (S485), Figure V V OD Change in Magnitude of Driver Differential Output = 27Ω or = 5Ω, Figure 1.2 V Voltage for Complementary Output States V OC Driver Common-Mode Output Voltage = 27Ω or = 5Ω, Figure 1 3 V V OC Change in Magnitude of Driver Common-Mode = 27Ω or = 5Ω, Figure 1.2 V Output Voltage for Complementary Output States V IH Input High Voltage,, E 2 V V IL Input Low Voltage,, E.8 V I IN1 Input Current,, E ±2 µ I IN2 Input Current (, ) =, = V or 5.25V, V IN = 12V.3 m =, = V or 5.25V, V IN = 7V.15 m V TH Differential Input Threshold Voltage for eceiver 7V V CM 12V.2.2 V V TH eceiver Input Hysteresis V CM = V 45 mv V OH eceiver Output High Voltage I O = 4m, V ID = 2mV 3.5 V V OL eceiver Output Low Voltage I O = 4m, V ID = 2mV.4 V I OZ Three-State (High Impedance) Output = Max,.4V V O 2.4V ±1 µ Current at eceiver IN eceiver Input esistance 7V V CM 12V 7 96 kω I CC Supply Current No Load, Output Enabled 12 2 µ No Load, Output Disabled 8 12 µ I SHDN Supply Current in Shutdown Mode = V, E = 1 1 µ I OSD1 Driver Short-Circuit Current, V OUT = HIGH 7V V O 12V m I OSD2 Driver Short-Circuit Current, V OUT = LOW 7V V O 12V m I OS eceiver Short-Circuit Current V V O 7 85 m 5-5

3 ELECTICL CHCTEISTICS 4 C T 85 C, = 5V (Note 4) unless otherwise noted. LTC1487 SYMOL PMETE CONTIONS MIN TYP MX UNITS V OD1 Differential Driver Output Voltage (Unloaded) I O = 5 V V OD2 Differential Driver Output Voltage (with Load) = 5Ω (S422) 2. V = 27Ω (S485), Figure V V OC Driver Common-Mode Output Voltage = 27Ω or = 5Ω, Figure 1 3 V V TH Differential Input Threshold Voltage for eceiver 7V V CM 12V.2.2 V V TH eceiver Input Hysteresis V CM = V 45 mv I CC Supply Current No Load, Output Enabled 12 2 µ No Load, Output Disabled 8 12 µ I SHDN Supply Current in Shutdown Mode = V, E = 1 1 µ t PLH Driver Input to Output FF = 54Ω, C L1 = C L2 = 1pF, ns t PHL Driver Input to Output (Figures 3, 5) ns t SKEW Driver Output to Output 1 6 ns t r, t f Driver ise or Fall Time 15 2 ns t PLH eceiver Input to Output FF = 54Ω, C L1 = C L2 = 1pF, ns t PHL eceiver Input to Output (Figures 3, 7) ns t SKD t PLH t PHL Differential eceiver Skew 13 ns f MX Maximum Data ate 25 kbps SWITCHI G CHCTEISTICS U C T 7 C, = 5V (Notes 2, 3) unless otherwise noted. SYMOL PMETE CONTIONS MIN TYP MX UNITS t PLH Driver Input to Output FF = 54Ω, C L1 = C L2 = 1pF, ns t PHL Driver Input to Output (Figures 3, 5) ns t SKEW Driver Output to Output 25 6 ns t r, t f Driver ise or Fall Time ns t ZH Driver Enable to Output High C L = 1pF (Figures 4, 6), S2 Closed 1 15 ns t ZL Driver Enable to Output Low C L = 1pF (Figures 4, 6), S1 Closed 1 15 ns t LZ Driver Disable Time from Low C L = 15pF (Figures 4, 6), S1 Closed ns t HZ Driver Disable Time from High C L = 15pF (Figures 4, 6), S2 Closed ns t PLH eceiver Input to Output FF = 54Ω, C L1 = C L2 = 1pF, ns t PHL eceiver Input to Output (Figures 3, 7) ns t SKD t PLH t PHL Differential eceiver Skew 13 ns t ZL eceiver Enable to Output Low C L = 15pF (Figures 2, 8), S1 Closed 2 5 ns t ZH eceiver Enable to Output High C L = 15pF (Figures 2, 8), S2 Closed 2 5 ns t LZ eceiver Disable from Low C L = 15pF (Figures 2, 8), S1 Closed 2 5 ns t HZ eceiver Disable from High C L = 15pF (Figures 2, 8), S2 Closed 2 5 ns f MX Maximum Data ate 25 kbps t SHDN Time to Shutdown =, E = ns 5-51

4 SWITCHI G CHCTEISTICS U C T 7 C, = 5V (Notes 2, 3) unless otherwise noted. SYMOL PMETE CONTIONS MIN TYP MX UNITS t ZH(SHDN) Driver Enable from Shutdown to Output High C L = 1pF (Figures 4, 6), S2 Closed 2 ns t ZL(SHDN) Driver Enable from Shutdown to Output Low C L = 1pF (Figures 4, 6), S1 Closed 2 ns t ZH(SHDN) eceiver Enable from Shutdown to Output High C L = 15pF (Figures 2, 8), S2 Closed 2 ns t ZL(SHDN) eceiver Enable from Shutdown to Output Low C L = 15pF (Figures 2, 8), S1 Closed 2 ns The denotes specifications which apply over the full operating temperature range. Note 1: bsolute maximum ratings are those beyond which the safety of the device cannot be guaranteed. Note 2: ll currents into device pins are positive; all currents out ot device pins are negative. ll voltages are referenced to device ground unless otherwise specified. Note 3: ll typicals are given for = 5V and T = 25 C. Note 4: The LTC1487 is not tested and is not quality-assurance sampled at 4 C and at 85 C. These specifications are guaranteed by design, correlation, and/or inference from C, 25 C and/or 7 C tests. TYPICL PEFOMNCE CHCTEISTICS U W SUPPLY CUENT (µ) Supply Current vs Temperature THEML SHUTDOWN WITH VE ENLED ND NOMINL LOD VE ENLED WITH NO LOD VE SLED WITH NO LOD TEMPETUE ( C) CUENT (m) Driver Differential Output Voltage vs Output Current T = 25 C VOLTGE (V) FFEENTIL VOLTGE (V) Driver Differential Output Voltage vs Temperature L = 54Ω TEMPETUE ( C) LTC1487 TPC1 LTC1487 TPC2 LTC1487 TPC3 CUENT (m) Driver Output Low Voltage vs Output Current T = 25 C VOLTGE (V) LTC1487 TPC4 CUENT (m) Driver Output High Voltage vs Output Current T = 25 C VOLTGE (V) LTC1487 TPC5 TIME (ns) Driver Skew vs Temperature TEMPETUE ( C) LTC1487 G6 5-52

5 E µ FU CTIO TLES U U LTC1487 Transmitting INPUTS S E X X 1 1 X Z Z 1 X Z* Z* *Shutdown mode LTC1487 eceiving INPUTS S E.2V 1.2V Inputs Open 1 1 X Z* *Shutdown mode TEST CICUITS V OD V OC ECEIVE TEST POINT C L 1k S1 S2 1k LTC1487 F1 LTC1487 F2 Figure 1. Driver DC Test Load Figure 2. eceiver Timing Test Load 3V FF C L1 C L2 E 15pF UN TEST 5Ω C L S1 S2 LTC1487 F3 LTC1487 F4 Figure 3. Driver/eceiver Timing Test Circuit Figure 4. Driver Timing Test Load 5-53

6 SWITCHI G TI E WVEFO S U W W 3V V f = 1MHz, t r 1ns, t f 1ns t PLH t PHL 1/2 V O V O V V O V O 1/2 VO 1% t r t SKEW 9% V FF = V() V() t f t SKEW 9% 1% LTC1487 F5 Figure 5. Driver Propagation Delays 3V V f = 1MHz, t r 1ns, t f 1ns 5V, V OL t ZL(SHDN), t ZL 2.3V NOMLLY LOW t LZ.5V V OH, V 2.3V t ZH(SHDN), t ZH NOMLLY HIGH t HZ.5V LTC1487 F6 Figure 6. Driver Enable and Disable Times V OH V OL t PHL f = 1MHz, t r 1ns, t f 1ns t PLH V OD2 V INPUT V V OD2 LTC1487 F7 Figure 7. eceiver Propagation Delays E 3V V f = 1MHz, t r 1ns, t f 1ns 5V t ZL(SHDN), t ZL NOMLLY LOW t LZ.5V V t ZH(SHDN), t ZH NOMLLY HIGH t HZ.5V LTC1487 F8 Figure 8. eceiver Enable and Disable Times 5-54

7 µ LOGIC P1 N1 SD3 SD4 D1 D2 LTC1487 F1 Figure 1. LTC1487 Output Stage P1 D1 LOGIC N1 D2 LTC1487 F9 Figure 9. Conventional CMOS Output Stage 5-55

8 µ µ µ µ µ µ E E µ E E µ µ µ µ TTL IN t r, t f < 6ns D 1pF 1Ω 1pF Figure 11. eceiver Propagation Delay Test Circuit LTC1487 F11 ECEIVE OUT 5-56