Linear Technology LTC1322IN, LTC1322CS, LTC1335IS, LTC1335CN, LTC1335 Datasheet

FEATURES

■LTC1321: 2-EIA562/RS232 Transceivers/2-RS485 Transceivers

■LTC1322: 4-EIA562/RS232 Transceivers/2-RS485 Transceivers

■LTC1335: 4-EIA562 Transceivers/2-RS485 Transceivers with OE

■LTC1321/LTC1322 Have the Same Pinout as SP301/SP302

■LTC1335 Features Receiver Three-State Outputs

■Low Supply Current: 1mA Typical

■15mA Supply Current in Shutdown

■120kBaud in EIA/TIA-562 or RS232 Mode

■10MBaud in RS485/RS422 Mode

■Self-Testing Capability in Loopback Mode

■Power-Up/Down Glitch-Free Outputs

■Driver Maintains High Impedance in Three-State, Shutdown or With Power Off

■Thermal Shutdown Protection

■I/O Lines Can Withstand ±25V

■Withstands Repeated 10kV ESD Pulses

APPLICATIOUS

■Low Power RS485/RS422/EIA562/RS232 Interface

■Cable Repeater

■Level Translator

LTC1321/LTC1322/LTC1335

RS232/EIA562/RS485

Transceivers

DESCRIPTIOU

The LTC1321/LTC1322/LTC1335 are low power CMOS bidirectionaltransceivers,eachfeaturingtworeconfigurable interface ports. Each can be configured as two RS485 differential ports, as two single-ended ports, or as one RS485 differential port and one single-ended port. The LTC1321/LTC1322 can provide RS232 or EIA562 compatible single-ended outputs; the LTC1335 provides EIA562 compatible outputs and additionally includes an output enable pin, allowing the receiver logic level outputs to be three-stated.

The RS232/EIA562 transceivers operate to 120kbaud and are in full compliance with EIA/TIA-562 specification. The RS485 transceivers operate to 10Mbaud and are in full compliance with RS485 and RS422 specifications. All interface drivers feature short-circuit and thermal shutdown protection. An enable pin allows RS485 driver outputs to be forced into high impedance which is maintained even when the outputs are forced beyond supply rails or power is off. Both driver outputs and receiver inputs feature ±10kV ESD protection. A loopback mode connects the driver outputs back to the receiver inputs for diagnostic self-test.

The LTC1321/LTC1322 can support RS232 voltage levels when 6.5V £ VDD £ 10V and – 6.5V ³ VEE ³ – 10V. The LTC1335 supports receiver output enable but not RS232 levels. A shutdown mode reduces the ICC supply current to 15mA.

TYPICAL APPLICATIOU

VCC1		24							24	VCC2
5V		1		2			11		1	5V
		22				RS485 INTERFACE			15
	RX OUT			3			10			RX OUT
	DR ENABLE	21			120Ω	120Ω			16	DR ENABLE
				4			9
		20							17
	DR IN			5	4000-FT 24-GAUGE TWISTED PAIR		8			DR IN
	5V	19		6	5V		7		19	5V
		18	LTC1322	7			5V	LTC1322	18
	5V				0V		6			5V
						EIA562 INTERFACE	0V		22
		17		8			3			RX OUT
	DR IN
		16		9			2		23
	DR IN									RX OUT
		15		10			5		20
	RX OUT									DR IN
		14		11			4		21
	RX OUT									DR IN
		13		12			12		13
	VEE1									VEE2
	–5V									–5V
										1321/22/35 TA01

1

LTC1321/LTC1322/LTC1335

ABSOLUTE

WAXIWUW

RATIUGS

Supply Voltage				Output Voltage
VCC ....................................................................			6.5V	Drivers .................................................		– 25V to 25V
VDD (LTC1321/LTC1322 Only)			........................... 10V	Receivers ...............................	– 0.3V to (VCC + 0.3V)
VEE ...................................................................			– 10V	Output Short-Circuit Duration .........................		Indefinite
Input Voltage				Operating Temperature Range		0°C to 70°C
Drivers ...................................			– 0.3V to (V CC + 0.3V)	LTC1321C/LTC1322C/LTC1335C .........
Receivers .............................................			– 25V to 25V	LTC1321I/LTC1322I/LTC1335I	.........	– 40°C to 85°C
		LB, SEL1,		Storage Temperature Range		– 65°C to 150°C
ON/OFF,
SEL2, OE ............................			– 0.3V to (V CC + 0.3V)	Lead Temperature (Soldering, 10 sec)................		300°C

PACKAGE/ORDER IUFORWATIOU

2 RS485 DRIVERS/RECEIVERS	2 RS485 DRIVERS/RECEIVERS	2 RS485 DRIVERS/RECEIVERS
2 EIA/TIA-562 DRIVERS/RECEIVERS	4 EIA/TIA-562 DRIVERS/RECEIVERS	4 EIA/TIA-562 DRIVERS/RECEIVERS
TOP VIEW	TOP VIEW	TOP VIEW

VDD	1	24	VCC	VDD	1	24	VCC	OE	1	24	VCC
B1	2	23	NC	B1	2	23	RB1	B1	2	23	RB1
A1	3	22	RA1	A1	3	22	RA1	A1	3	22	RA1
Z1	4	21	DE1	Z1	4	21	DZ1/DE1	Z1	4	21	DZ1/DE1
Y1	5	20	DY1	Y1	5	20	DY1	Y1	5	20	DY1
SEL1	6	19	LB	SEL1	6	19	LB	SEL1	6	19	LB
SEL2	7	18	ON/OFF	SEL2	7	18	ON/OFF	SEL2	7	18	ON/OFF
Y2	8	17	DY2	Y2	8	17	DY2	Y2	8	17	DY2
Z2	9	16	DE2	Z2	9	16	DZ2/DE2	Z2	9	16	DZ2/DE2
A2	10	15	RA2	A2	10	15	RA2	A2	10	15	RA2
B2	11	14	NC	B2	11	14	RB2	B2	11	14	RB2
GND	12	13	VEE	GND	12	13	VEE	GND	12	13	VEE

N PACKAGE			S PACKAGE	N PACKAGE	S PACKAGE	N PACKAGE	S PACKAGE
24-LEAD PLASTIC DIP			24-LEAD PLASTIC SOL	24-LEAD PLASTIC DIP	24-LEAD PLASTIC SOL	24-LEAD PLASTIC DIP	24-LEAD PLASTIC SOL
T	JMAX	= 125°C, θ = 75°C/W (N)		TJMAX = 125°C, θJA = 75°C/W (N)		TJMAX = 125°C, θJA = 75°C/W (N)
		JA		TJMAX = 125°C, θJA = 85°C/W (S)		TJMAX = 125°C, θJA = 85°C/W (S)
T		= 125°C, θ = 85°C/W (S)
	JMAX	JA
	ORDER PART			ORDER PART		ORDER PART
		NUMBER		NUMBER		NUMBER
		LTC1321CN		LTC1322CN		LTC1335CN
		LTC1321CS		LTC1322CS		LTC1335CS
		LTC1321IN		LTC1322IN		LTC1335IN
		LTC1321IS		LTC1322IS		LTC1335IS

Consult factory for Military grade parts.

2

LTC1321/LTC1322/LTC1335

DC ELECTRICAL CHARACTERISTICS

VCC = VDD (LTC1321/LTC1322) = 5V ±5%, VEE = –5V ±5% (Notes 2, 3)

SYMBOL

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

RS485 Driver (SEL1 = SEL2 = HIGH)

VOD1

Differential Driver Output Voltage (Unloaded)

IO = 0

●

5

V

VOD2

Differential Driver Output Voltage (With Load)

Figure 1, R = 50W (RS422)

●

2.0

5

V

Figure 1, R = 27W (RS485)

●

1.5

5

V

DVOD

Change in Magnitude of Driver Differential

Figure 1, R = 27W or R = 50W

●

0.2

V

Output Voltage for Complementary Output States

VOC

Driver Common-Mode Output Voltage

Figure 1, R = 27W or R = 50W

●

3

V

D½VOC½

Change in Magnitude of Driver Common-Mode

Figure 1, R = 27W or R = 50W

●

0.2

V

Output Voltage for Complementary Output States

IOSD

Driver Short-Circuit Current

– 7V £ VO

£ 12V, VO = HIGH

●

35

250

mA

– 7V £ VO

£ 12V, VO = LOW (Note 4)

●

10

250

mA

IOZD

Three-State Output Current (Y, Z)

– 7V £ VO £ 12V

●

±5

±500

mA

EIA/TIA-562 Driver (SEL1 = SEL2 = LOW)

VO

Output Voltage Swing

Figure 4, RL = 3k, Positve

●

3.7

4.2

V

Figure 4, RL = 3k, Negative

●

– 3.7

– 4.3

V

IOSD

Output Short-Circuit Current

VO = 0V

●

±11

±60

mA

Driver Inputs and Control Inputs

VIH

Input High Voltage

D, DE, ON/OFF,

SEL1, SEL2, LB

●

2

V

OE (LTC1335)

●

2

V

VIL

Input Low Voltage

SEL1, SEL2,

0.8

V

D, DE, ON/OFF,

LB

●

OE (LTC1335)

●

0.8

V

IIN

Input Current

D, SEL1, SEL2

●

– 4

±10

mA

DE, ON/OFF, LB

●

– 15

mA

OE (LTC1335)

●

4

15

mA

RS485 Receiver (SEL1 = SEL2 = HIGH)

VTH

Differential Input Threshold Voltage

– 7V £ VCM £ 7V, Commercial

●

– 0.2

0.2

V

– 7V £ VCM £ 7V, Industrial

●

– 0.3

0.3

V

DVTH

Input Hysteresis

VCM = 0V

●

70

mV

IIN

Input Current (A, B)

– 7V £ VIN £ 12V

●

±1

mA

RIN

Input Resistance

– 7V £ VIN £ 12V

●

12

24

kW

EIA/TIA-562 Receiver (SEL1 = SEL2 = LOW)

VTH

Receiver Input Voltage Threshold

Input Low Threshold

●

0.8

1.1

V

Input High Threshold

●

1.7

2.4

V

DVTH

Receiver Input Hysteresis

●

0.1

0.6

1.0

V

RIN

Receiver Input Resistance

VIN = ±10V

3

5

7

kW

Receiver

Output

VOH

Receiver Output High Voltage

IO = – 3mA, VIN = 0V, SEL1 = SEL2 = LOW

●

3.5

4.6

V

VOL

Receiver Output Low Voltage

IO = 3mA, VIN = 3V, SEL1 = SEL2 = LOW

●

0.2

0.4

V

IOSR

Short-Circuit Current

0V £ VO £ VCC

●

7

85

mA

IOZR

Three-State Output Current

ON

= 0V

±10

mA

/OFF

●

OE = VCC (LTC1335)

●

±10

mA

3

LTC1321/LTC1322/LTC1335

DC ELECTRICAL CHARACTERISTICS

VCC = VDD (LTC1321/LTC1322) = 5V ±5%, VEE = – 5V ±5% (Notes 2, 3)

SYMBOL		PARAMETER	CONDITIONS				MIN	TYP	MAX		UNITS
Supply	Currents
ICC		VCC Supply Current	No Load (SEL1 = SEL2 = HIGH)			●		1000	2000		mA
					= 0V			15	50		mA
			Shutdown, ON/OFF			●
IDD		VDD Supply Current (LTC1321/LTC1322)	No Load (SEL1 = SEL2 = LOW)			●		300	1000		mA
					= 0V			0.1	50		mA
			Shutdown, ON/OFF			●
IEE		VEE Supply Current	No Load (SEL1 = SEL2 = HIGH)			●		– 1000	– 2000		mA
					= 0V			– 0.1	– 50		mA
			Shutdown, ON/OFF			●

ACDC ELECTRICAL CHARACTERISTICS

VCC = VDD (LTC1321/LTC1322) = 5V ±5%, VEE = – 5V ±5% (Notes 2, 3)

SYMBOL		PARAMETER	CONDITIONS		MIN	TYP	MAX		UNITS
EIA/TIA-562 Mode (SEL1 = SEL2 = LOW)
SR		Slew Rate	Figure 4, RL = 3k, CL = 15pF	●		14	30		V/ms
			Figure 4, RL = 3k, CL = 1000pF	●	4	7			V/ms
tT		Transition Time	Figure 4, RL = 3k, CL = 2500pF	●	0.22	1.9	3.1		ms
tPLH		Driver Input to Output	Figures 4,10, RL = 3k, CL = 15pF	●		0.6	4		ms
tPHL		Driver Input to Output	Figures 4,10, RL = 3k, CL = 15pF	●		0.6	4		ms
tPLH		Receiver Input to Output	Figures 5,11	●		0.3	6		ms
tPHL		Receiver Input to Output	Figures 5,11	●		0.4	6		ms
RS485 Mode (SEL1 = SEL2 = HIGH)
tPLH		Driver Input to Output	Figures 2,7, RL = 54W, CL = 100pF	●	20	40	70		ns
tPHL		Driver Input to Output	Figures 2,7, RL = 54W, CL = 100pF	●	20	40	70		ns
tSKEW		Driver Output to Output	Figures 2,7, RL = 54W, CL = 100pF	●		5	15		ns
tr, tf		Driver Rise or Fall Time	Figures 2,7, RL = 54W, CL = 100pF	●	3	15	40		ns
tZL		Driver Enable to Output Low	Figures 3,8, CL = 100pF, S1 Closed	●		50	90		ns
tZH		Driver Enable to Output High	Figures 3,8, CL = 100pF, S2 Closed	●		50	90		ns
tLZ		Driver Disable from Low	Figures 3,8, CL = 15pF, S1 Closed	●		50	90		ns
tHZ		Driver Disable from High	Figures 3,8, CL = 15pF, S2 Closed	●		60	90		ns
tPLH		Receiver Input to Output	Figures 2,9, RL = 54W, CL = 100pF	●	20	60	140		ns
tPHL		Receiver Input to Output	Figures 2,9, RL = 54W, CL = 100pF	●	20	70	140		ns
tSKEW		Differential Receiver Skew, ½tPLH-tPHL½	Figures 2,9, RL = 54W, CL = 100pF	●		10			ns
Receiver	Output Enable/Disable (LTC1335)
tZL		Receiver Enable to Output Low	Figures 6,12, CL = 15pF, S1 Closed	●		40	90		ns
tZH		Receiver Enable to Output High	Figures 6,12, CL = 15pF, S2 Closed	●		40	90		ns
tLZ		Receiver Disable from Low	Figures 6,12, CL = 15pF, S1 Closed	●		40	90		ns
tHZ		Receiver Disable from High	Figures 6,12, CL = 15pF, S2 Closed	●		50	90		ns

The ● denotes specifications which apply over the full operating temperature range.

Note 1: Absolute maximum ratings are those values beyond which the safety of the device cannot be guaranteed.

Note 2: All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to device ground unless otherwise specified.

Note 3: All typicals are given at VCC = VDD (LTC1321/LTC1322) = 5V, VEE = – 5V, and TA = 25°C.

Note 4: Short-circuit current for RS485 driver output low state folds back above VCC. Peak current occurs around VO = 3V.

4

LTC1321/LTC1322/LTC1335

TYPICAL PERFORWAUCE CHARACTERISTICS

RS485 Driver Differential Output Voltage vs Temperature

	2.6
(V)	2.5		RL =	54Ω
	2.4
VOLTAGE
	2.3
OUTPUT	2.2
	2.1
DIFFERENTIAL	2.0
	1.9
	1.8
	1.7
	1.6

–50 –25 0 25 50 75 100 125 TEMPERATURE (°C)

1321 G01

RS485 Driver Output High Voltage vs Output Current

	–80
	–70					TA	= 25°C
(mA)	–60
CURRENT	–50
OUTPUT	–40
	–30
	–20
	–10
	0

0 1 2 3 4 5 OUTPUT VOLTAGE (V)

1321 G04

EIA562 Driver Output Voltage vs Temperature

5

4

OUTPUT HIGH

(V)

3

2

VOLTAGE

1

RL = 3k

0

OUTPUT

–2

–1

–3

–4

OUTPUT LOW

–5

–50 –25 0 25 50 75 100 125 TEMPERATURE (°C)

1321 G07

RS485 Driver Differential Output Current vs Output Voltage

	70
(mA)	60					TA	= 25°C
CURRENT	50
OUTPUT	40
	30
DIFFERENTIAL	20
	10
	0

0 1 2 3 4 5 DIFFERENTIAL OUTPUT VOLTAGE (V)

1321 G02

RS485 Driver Output Low Voltage vs Output Current

	120
			TA =	25°C
(mA)	100
	80
CURRENT
	60
OUTPUT
	40
	20
	0
			1		2	3		4		5
	0

OUTPUT VOLTAGE (V)

1321 G05

EIA562 Driver Output Voltage vs Supply Voltage

	10
	8		RL =	3k
			TA = 25°C
	6		VEE =	–VDD
(V)										OUTPUT HIGH
	4
VOLTAGE	0
OUTPUT	2
	–4
	–2
	–6									OUTPUT LOW
	–8
	–10
			5		6		7			8		9			10
	4

VDD SUPPLY VOLTAGE (V)

1321 G08

RS485 Driver Skew vs

Temperature

	15
	12
s)	9
TIME (μ	6
	3
	0

–50 –25 0 25 50 75 100 125 TEMPERATURE (°C)

1321 G03

RS485 Driver Output Short-Circuit Current vs Temperature

(mA)	160
	140
CURRENT
	120
CIRCUIT-					SINK
	100				(VOUT = 5V)
SHORT
	80
			SOURCE
OUTPUT	60		(VOUT = 0V)
	40

–50 –25 0 25 50 75 100 125 TEMPERATURE (°C)

1321 G19

EIA562 Driver Output Short-Circuit Current vs Temperature

	18
(mA)													VOUT	= 0V
	16
CURRENT
	14
CIRCUIT-
	12							SOURCE
SHORT
	10					SINK
OUTPUT	8
	6
			–25		0	25		50		75			100		125
	–50

TEMPERATURE (°C)

1321 G09

5

LTC1321/LTC1322/LTC1335

TYPICAL PERFORWAUCE CHARACTERISTICS

	Receiver Output High Voltage																										Receiver Output Low Voltage
	vs Temperature																										vs Temperature
	5.0																										0.5
	4.9					IOUT	= 3mA																				0.4			IOUT = 3mA
(V)	4.8																									(V)
	4.7
VOLTAGE	4.6																									VOLTAGE	0.3
OUTPUT	4.5																									OUTPUT	0.2
	4.3
	4.4
	4.2																										0.1
	4.1																										0
	4.0
													25		50									125											25						50									125
	–50					–25			0									75			100						–50			–25			0											75			100
											TEMPERATURE (°C)																							TEMPERATURE (°C)
																							1321 G10																										1321 G11
			Receiver Output Current																								Receiver Output Current
			vs Output High Voltage																								vs Output Low Voltage
	120																										40
																														TA =		25°C
	18					TA =		25°C																			35
	16
(mA)																										(mA)	30
	14
CURRENT	12																									CURRENT	25
																											20
OUTPUT	10																									OUTPUT
	8																										15
	6
																											10
	4
																											5
	2
																											0
	0
						2.5			3.0						3.5			4.0			4.5			5.0						0.5					1.0						1.5			2.0			2.5			3.0
	2.0																										0
									OUTPUT VOLTAGE (V)																								OUTPUT VOLTAGE (V)
																							1321 G13																										1321 G14
	Driver Output Leakage Current																										Supply Current in RS485 Mode
	(Disable/Shutdown) vs Temperature																										vs Temperature (Both Ports)
	±400																										1.2
																																															RL		= ∞
A)	±350																										1.0									ICC
(μ	±300																									(mA)CURRENTSUPPLY
CURRENTLEAKAGEOUTPUT
																											0.2								–IEE
																											0.8
	±250
	±200																										0.6
	±150																										0.4
	±100
	±50
																																			–IDD
	0																										0
						–25			0				25		50			75			100			125						–25			0		25						50			75			100			125
	–50																										–50
											TEMPERATURE (°C)																							TEMPERATURE (°C)
																							1321 G06																										1321 G17

RS485 Receiver ½tPLH – tPHL½ vs Temperature

	20
	18
	16
	14
(ns)	12
	10
TIME
	8
	6
	4
	2
	0
							25		50						125
	–50		–25		0						75		100
						TEMPERATURE (°C)
														1321 G12

	EIA562 Receiver Input Threshold
	Voltage vs Temperature
(V)	2.0
	1.8
													INPUT HIGH
VOLTAGE	1.6
THRESHOLD	1.2
	1.4
INPUT													INPUT LOW
	1.0
	0.8
					–25		0		25			50				75		100		125
	–50
								TEMPERATURE (°C)
																			1321 G15
		Supply Current in EIA562 Mode
		vs Temperature (Both Ports)
	500
	450				RL = ∞
	400
μA)												–IEE
	350
(										–IDD
CURRENT	300
												ICC
SUPPLY	250
	200
	150
	100
	50
	0
									25			50								125
	–50				–25		0									75		100

TEMPERATURE (°C)

1321 G18

6