Linear Technology LT1181AIN, LT1181ACSW, LT1181ACN, LT1180AMJ, LT1180AISW Datasheet

FEATURES

■ESD Protection over ±10kV

■Uses Small Capacitors: 0.1 F

■120kBaud Operation for RL = 3k, CL = 2500pF

■250kBaud Operation for RL = 3k, CL = 1000pF

■Outputs Withstand ±30V Without Damage

■CMOS Comparable Low Power: 40mW

■Operates from a Single 5V Supply

■Rugged Bipolar Design

■Outputs Assume a High Impedance State When Off or Powered Down

■Meets All RS232 Specifications

■Available With or Without Shutdown

■Absolutely No Latch-up

■Available in SO Package

APPLICATIOUS

■Portable Computers

■Battery-Powered Systems

■Power Supply Generator

■Terminals

■Modems

LT1180A/LT1181A

Low Power 5V RS232 Dual Driver/Receiver with 0.1 F Capacitors

DESCRIPTIOU

The LT®1180A/LT1181A are dual RS232 driver/receiver pairs with integral charge pump to generate RS232 voltage levels from a single 5V supply. These circuits feature rugged bipolar design to provide operating fault tolerance and ESD protection unmatched by competing CMOS designs. Using only 0.1 F external capacitors, these circuits consume only 40mW of power, and can operate to 120k baud even while driving heavy capacitive loads. New ESD structures on the chip allow the LT1180A/LT1181A to survive multiple ±10kV strikes, eliminating the need for costly TransZorbs® on the RS232 line pins. The LT1180A/ LT1181A are fully compliant with EIA RS232 standards. Driver outputs are protected from overload, and can be shorted to ground or up to ±30V without damage. During shutdown or power-off conditions, driver and receiver outputs are in a high impedance state, allowing line sharing.

The LT1181A is available in 16-pin DIP and SO packages. The LT1180A is supplied in 18-pin DIP and SO packages for applications which require shutdown.

, LTC and LT are registered trademarks of Linear Technology Corporation.

TransZorb is a registered trademark of General Instruments, GSI

TYPICAL APPLICATIOU

	+	2		17	5V INPUT		Output Waveforms
0.1 F
		4		3		+ OUT
					V
				+
		LT1180A		0.1 F			DRIVER
		5		7		– OUT	OUTPUT
	+				V		RL = 3k
				0.1			CL = 2500pF
0.1 F		6			F
				+
		12
				15	RS232 OUTPUT		RECEIVER
LOGIC
							ROUTPUT
INPUTS
		11		8	RS232 OUTPUT		CL = 50pF
		13		14	RS232 INPUT
							INPUT
LOGIC			5k
OUTPUTS
		10		9	RS232 INPUT
ON/OFF		18	5k	16
						LT1180A • TA01

LT1180A • TA02

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LT1180A/LT1181A

ABSOLUTE

WAXIWUW

RATI GS	(Note 1)
U

Supply Voltage (VCC)	................................................ 6V
V+ ........................................................................	13.2V
V– ......................................................................	– 13.2V
Input Voltage	V – to V +
Driver ...........................................................
Receiver ...............................................	– 30V to 30V
ON/OFF .................................................	– 0.3V to 12V
Output Voltage	V + – 30V to V – + 30V
Driver ......................................
Receiver ....................................	– 0.3V to V CC + 0.3V

Short-Circuit Duration
V+ ...................................................................	30 sec
V– ...................................................................	30 sec
Driver Output ..............................................	Indefinite
Receiver Output ..........................................	Indefinite
Operating Temperature Range	– 40°C to 85°C
LT1180AI/LT1181AI ..........................
LT1180AC/LT1181AC .............................	0°C to 70°C
Storage Temperature Range ................	– 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................	300°C

PACKAGE/ORDER IUFORWATIOU

		TOP VIEW			ORDER PART				TOP VIEW		ORDER PART
						C1+		1		VCC
	NC	1	18	ON/OFF	NUMBER				16		NUMBER
	C1+	2	17	VCC		V+		2	15	GND
	V+	3	16	GND
					LT1180ACN	C1	–	3	14	TR1 OUT	LT1181ACN
	C1–	4	15	TR1 OUT
	C2+	5	14	REC1 IN	LT1180ACSW	C2+		4	13	REC1 IN	LT1181ACSW
	C2–	6	13	REC1 OUT	LT1180AIN	C2	–	5	12	REC1 OUT	LT1181AIN
	V–	7	12	TR1 IN	LT1180AISW	V	–	6	11	TR1 IN	LT1181AISW
	TR2 OUT	8	11	TR2 IN		TR2 OUT		7	10	TR2 IN
						REC2 IN		8	9	REC2 OUT
	REC2 IN	9	10	REC2 OUT
	N PACKAGE		SW PACKAGE			N PACKAGE			SW PACKAGE
						16-LEAD PDIP 16-LEAD PLASTIC SO (WIDE)
	18-LEAD PDIP 18-LEAD PLASTIC SO (WIDE)
						TJMAX = 125°C, θJA = 90°C/ W, θJC = 46°C/W (N)
	TJMAX = 125°C, θJA		= 80°C/ W, θJC = 36°C/W (N)
						TJMAX = 125°C, θJA = 95°C/ W, θJC = 27°C/W (SW)
	TJMAX = 125°C, θJA = 90°C/ W, θJC = 26°C/W (SW)

J PACKAGE	LT1180AMJ	J PACKAGE	LT1181AMJ
18-LEAD CERDIP		16-LEAD CERDIP
TJMAX = 150°C, θJA = 100°C/W, θJC = 40°C/W (J)		TJMAX = 150°C, θJA = 100°C/W, θJC = 40°C/W (J)

OBSOLETE PACKAGE	OBSOLETE PACKAGE
Consider N Package for Alternate Source	Consider N Package for Alternate Source

Consult LTC Marketing for parts specified with wider operating temperature ranges.

ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the operating temperature range (0°C ≤ TA ≤ 70°C for commercial grade, and –40°C ≤ TA ≤ 85°C for industrial grade. (Note 2)

PARAMETER			CONDITIONS		MIN	TYP	MAX	UNITS
Power Supply Generator
V + Output						7.9		V
V – Output						– 7.0		V
Supply Current (VCC)			(Note 3), TA = 25°C			9	13	mA
				●			16	mA
Supply Current When OFF (VCC)			Shutdown (Note 4) LT1180A Only	●		1	10	A
Supply Rise Time			C1 = C2 = C3 = C4 = 0.1 F			0.2		ms
Shutdown to Turn-On			LT1180A Only			0.2		ms
		Pin Thresholds	Input Low Level (Device Shutdown)		0.8	1.2		V
ON/OFF				●
			Input High Level (Device Enabled)	●		1.6	2.4	V
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LT1180A/LT1181A

ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the operating temperature range (0°C ≤ TA ≤ 70°C for commercial grade, and – 40°C ≤ TA ≤ 85°C for industrial grade. (Note 2)

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

ON/OFF

Pin Current

0V ≤ VON/OFF

≤ 5V

●

– 15

80

µA

Oscillator Frequency

130

kHz

Driver

Output Voltage Swing

Load = 3k to GND

Positive

5.0

7.5

V

Negative

●

– 6.3

– 5.0

V

Logic Input Voltage Level

Input Low Level (VOUT = High)

●

1.4

0.8

V

Input High Level (VOUT = Low)

●

2.0

1.4

V

Logic Input Current

0.8V ≤ VIN ≤ 2.0V

●

5

20

µA

Output Short-Circuit Current

VOUT = 0V

±9

17

mA

Output Leakage Current

Shutdown VOUT = ±30V (Note 4)

●

10

100

µA

Date Rate (Note 7)

RL = 3k, CL = 2500pF

120

kBaud

RL = 3k, CL = 1000pF

250

kBaud

Slew Rate

RL = 3k, CL = 51pF

15

30

V/µs

RL = 3k, CL = 2500pF

4

7

V/µs

Propagation Delay

Output Transition tHL High-to-Low (Note 5)

0.6

1.3

µs

Output Transition tLH Low-to-High

0.5

1.3

µs

Receiver

Input Voltage Thresholds

Input Low Threshold (VOUT = High)

C Grade

●

0.8

1.3

V

Input High Threshold (VOUT = Low)

C Grade

●

1.7

2.4

V

Input LowI,

M Grade

●

0.2

1.3

V

Input HighI,

M Grade

●

1.7

3.0

V

Hysteresis

●

0.1

0.4

1.0

V

Input Resistance

VIN = ±10V

3

5

7

kΩ

Output Leakage Current

Shutdown (Note 4) 0 ≤ VOUT ≤ VCC

●

1

10

µA

Output Voltage

Output Low, IOUT = – 1.6mA

●

0.2

0.4

V

Output High, IOUT = 160µA (VCC = 5V)

●

3.5

4.2

V

Output Short-Circuit Current

Sinking Current, VOUT = VCC

–20

– 10

mA

Sourcing Current, VOUT = 0V

10

20

mA

Propagation Delay

Output Transition tHL High-to-Low (Note 6)

250

600

ns

Output Transition tLH Low-to-High

350

600

ns

Note 1: Absolute Maximum Ratings are those values beyond which the life of the device may be impaired.

Note 2: Testing done at VCC = 5V and VON/OFF = 3V, unless otherwise specified.

Note 3: Supply current is measured as the average over several charge pump cycles. C + = C – = C1 = C2 = 0.1µF. All outputs are open, with all driver inputs tied high.

Note 4: Supply current measurements in SHUTDOWN are performed with VON/OFF ≤ 0.1V.

Note 5: For driver delay measurements, RL = 3k and CL = 51pF. Trigger points are set between the driver’s input logic threshold and the output transition to the zero crossing (tHL = 1.4V to 0V and tLH = 1.4V to 0V).

Note 6: For receiver delay measurements, CL = 51pF. Trigger points are set between the receiver’s input logic threshold and the output transition to standard TTL/CMOS logic threshold (tHL = 1.3V to 2.4V and tLH = 1.7V to 0.8V).

Note 7: Data rate operation guaranteed by slew rate, short-circuit current and propagation delay tests.

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LT1180A/LT1181A

TYPICAL PERFORWAUCE CHARACTERISTICS

PEAK OUTPUT VOLTAGE (V)

Driver Maximum Output Voltage vs Load Capacitance

8.0

7.5

7.0
								20kBAUD
6.5
								60kBAUD
6.0
5.5								120kBAUD
5.0
0		1	2	3	4	5	6			7			8	9	10

LOAD CAPACITANCE (nF)

Driver Minimum Output Voltage
vs Load Capacitance	Driver Output Voltage

–4.0												10
												RL = 3k
												8
–4.5											VOLTAGEOUTPUTDRIVER(V)	6			VCC = 5.5V
VOLTAGEOUTPUTPEAK(V)				120kBAUD
												–6			VCC = 5V
–5.0												4
												2			VCC = 4.5V
					60kBAUD										OUTPUT HIGH
–5.5					20kBAUD							0			OUTPUT LOW
												–2
															VCC = 4.5V
–6.0												–4			VCC = 5V
															VCC = 5.5V
–6.5												–8
–7.0												–10		0	25	50	75		125
0	1	2	3	4	5	6	7	8	9	10		–55	–25					100
			LOAD CAPACITANCE (nF)											TEMPERATURE (°C)

LT1180A • TPC01

LT1180A • TPC02

LT1180A • TPC03

Receiver Input Thresholds

	3.00
	2.75
(V)	2.50
	2.25
VOLTAGE
	2.00					INPUT HIGH
THRESHOLD	1.75
	1.50					INPUT LOW
	1.25
	1.00
	0.75
	0.50
				0		25 50			75 100 125
	–55 –25

TEMPERATURE (°C)

LT1180A • TPC04

SUPPLY CURRENT (mA)

Supply Current vs Data Rate

50

2 DRIVERS ACTIVE

RL = 3k

40 CL = 2500pF

30

20

10

0

0

25

50

75

100

125

150

DATA RATE (kBAUD)

LT1180A • TPC05

THRESHOLD VOLTAGE (V)

ON/OFF Thresholds

3.0

2.5

2.0

ON THRESHOLD

1.5

1.0

OFF THRESHOLD

0.5

0		25	50	75	100 125
–55 –25	0

TEMPERATURE (°C)

LT1180A • TPC06

SUPPLY CURRENT (mA)

Supply Current

Driver Leakage in Shutdown

Driver Short-Circuit Current

25

20		2 DRIVERS LOADED RL = 3k

15

1 DRIVER LOADED RL = 3k

10

5		NO LOAD
0		0	25	50	75		125
–55	–25					100

TEMPERATURE (°C)

LT1180A • TPC07

100									30
								SHORT-CIRCUIT CURRENT (mA)	25						+
															ISC
10									20
									15
				VOUT = 30V											–
1									10						ISC
				VOUT = –30V
CURRENTLEAKAGEA)(
									5
0.1									0				50		100	125
–55	–25	0	25	50	75	100	125		–55	–25	0	25		75

TEMPERATURE (°C)	TEMPERATURE (°C)
LT1180A • TPC08	LT1180A • TPC09

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