ST ST26C31B User Manual

ST26C31B

CMOS quad 3-state differential line driver

Features
■	TTL input compatible
■ Typical propagation delay: 6 ns
■ Typical output skew: 0.5 ns
■ Output will not load line when VCC = 0 V
■	Meets the requirements of EIA standard	DIP-16	SO-16
	RS-422

■ Operation from single 5 V supply

■ 3-state outputs for connection to system buses

■ Low quiescent current

■ Available in surface mount

TSSOP16

Description

The ST26C31B is a quad differential line driver designed for digital data transmission over balanced lines and meets all the requirements of EIA standard RS-422 while retaining the low power characteristics of CMOS.

The ST26C31B accepts TTL or CMOS input levels and translates these to RS-422 output levels. This part uses special outputs circuitry common to all four drivers. All outputs are protected against damage due to electrostatic discharge by diode to VCC and ground.

Table 1.	Device summary
Order codes		Temperature range	Package	Packaging
ST26C31BN		-40 to 85 °C	DIP-16	25 parts per tube / 40 tube per box
ST26C31BDR		-40 to 85 °C	SO-16 (tape and reel)	2500 parts per reel
ST26C31BTR		-40 to 85 °C	TSSOP16 (tape and reel)	2500 parts per reel
June 2008			Rev 8	1/15
				www.st.com

Contents	ST26C31B

Contents

1	Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. 3
2	Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	5
3	Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	6
4	Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	8
5	Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	14

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ST26C31B	Pin configuration

1 Pin configuration

Figure 1. Pin connections

Table 2.	Pin description
Pin n°		Symbol					Name and function
1			AIN				Input A
2			AOUT				Channel A output
3					OUT		Channel A output
			A
4			EN				ENABLE
5				OUT			Channel B output
			B
6			BOUT				Channel B output
7			BIN				Input B
8			GND				Ground
9			CIN				Input C
10			COUT				Channel C output
11						OUT	Channel C output
			C
12			EN				ENABLE
13						OUT	Channel D output
			D
14			DOUT				Channel D output
15			DIN				Input D
16			VCC				Supply voltage

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	Pin configuration						ST26C31B
	Table 3.	Truth table
	Enable			Enable	Input	Output	Output
	L			H	X	Z	Z
	All other combinations of enable inputs				L	L	H
					H	H	L
	Note:	L = Low voltage state
		H = High logic state
		X = Don’t care
		Z = High impedance

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ST26C31B	Maximum ratings

2	Maximum ratings
Table 4.	Absolute maximum ratings (1) (2)
Symbol	Parameter	Value	Unit
VCC	Supply voltage	-0.5 to 7	V
VIN	DC input voltage	-0.5 to (VCC + 0.5)	V
VOUT	DC output voltage (high or low state)	-0.5 to 7	V
IIK	Clamp diode current	± 20	mA
IOUT	DC output current per pin	± 150	mA
ICC	DC VCC or gnd current	± 150	mA
TSTG	Storage temperature range	-65 to +150	°C

1.Absolute maximum ratings are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the device should be operated at these limits. The table of electrical characteristics provide conditions for actual device operation.

2.Unless otherwise specified, all voltage are referenced to ground. All currents into the device pins are positive; all currents out of the device pins are negative.

Table 5.	Recommended operating conditions
Symbol	Parameter	Value	Unit
VCC	Supply voltage	4.5 to 5.5	V
VIN	DC input voltage	0 to VCC	V
VOUT	DC output voltage (high or low state)	0 to VCC	V
VOUT	DC output voltage (VCC = 0 V or high impedance)	0 to 5	V
TA	Operating temperature range	-40 to +85	°C
tr, tf	Maximum enable input rise or fall times	500	ns

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