ST ST232AB, ST232AC User Manual

ST232AB

ST232AC

Very high speed, ultra low power consumption 5 V powered RS-232 drivers and receivers

Features

■Supply voltage range: 4.5 to 5.5 V

■Supply current no load (typ): 1.5 mA

■Transmitter output voltage swing (typ): ± 9 V

■ Transition slew rate (typ.): 12 V/µs
■ Receiver propagation delay (typ.): 0.1 µs
■	Receiver input voltage range: ± 30 V
■	Data rate (typ.): 400 kbps/s	SO-16	TSSOP16

■Operating temperature range:

–-40 to 85 °C

–0 to 70 °C

Description

The ST232AB/AC is a 2 driver, 2 receiver device	.
following EIA/TIA-232 and V.28 communication
standard. It is particularly suitable for applications
where ±12 V is not available. The ST232AB/AC
uses a single 5 V power supply and only four
external capacitors (0.1 µF). Typical applications
are in: portable computers, low power modems,
interfaces translation, battery powered RS-232
networks.

	Table 1.	Device summary
	Order codes		Temperature	Packages	Packaging
			range
	ST232ACDR		0 to 70 °C	SO-16 (tape and reel)	2500 parts per reel
	ST232ABDR		-40 to 85 °C	SO-16 (tape and reel)	2500 parts per reel
	ST232ACTR		0 to 70 °C	TSSOP16 (tape and reel)	2500 parts per reel
	ST232ABTR		-40 to 85 °C	TSSOP16 (tape and reel)	2500 parts per reel
	February 2008			Rev 9	1/16

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ST232AB - ST232AC

Contents

1	Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. 3
2	Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	4
3	Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	5
4	Typical application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	7
5	Typical performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . .	8
6	Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	10
7	Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	15

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ST232AB - ST232AC	Pin configuration

1 Pin configuration

Figure 1. Pin connections (top view)

Table 2.	Pin description
Pin n°		Symbol	Note
1		C1+	Positive terminal for the first charge pump capacitor
2		V+	Doubled voltage terminal
3		C1-	Negative terminal for the first charge pump capacitor
4		C2+	Positive terminal for the second charge pump capacitor
5		C2-	Negative terminal for the second charge pump capacitor
6		V-	Inverted voltage terminal
7		T2OUT	Second transmitter output voltage
8		R2IN	Second receiver input voltage
9		R2OUT	Second receiver output voltage
10		T2IN	Second transmitter input voltage
11		T1IN	First transmitter input voltage
12		R1OUT	First receiver output voltage
13		R1IN	First receiver input voltage
14		T1OUT	First transmitter output voltage
15		GND	Ground
16		VCC	Supply voltage

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Maximum ratings			ST232AB - ST232AC
2	Maximum ratings
Table 3.	Absolute maximum ratings
Symbol		Parameter	Value	Unit
VCC		Supply voltage	-0.3 to 6	V
V+		Extra positive voltage	(VCC - 0.3 to 13.2)	V
V-		Extra negative voltage	0.3 to -13.2	V
TIN		Transmitter input voltage range	-0.3 to (VCC + 0.3)	V
RIN		Receiver input voltage range	± 30	V
TOUT		Transmitter output voltage range	± 15	V
ROUT		Receiver output voltage range	-0.3 to (VCC + 0.3)	V
TSCTOUT		Short circuit duration on TOUT	infinite
Note:	Absolute maximum ratings are those values beyond which damage to the device may occur.
	Functional operation under these condition is not implied.

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ST232AB - ST232AC	Electrical characteristics

3

Electrical characteristics

Table 4.

Electrical characteristics

(C1 - C4 = 0.1 µF, VCC = 5 V ± 10 %, TA = -40 to 85 °C, unless otherwise specified. Typical

values are referred to TA = 25 °C).

Symbol

Parameter

Test condition

Min.

Typ.

Max.

Unit

ISUPPLY

VCC power supply current

No Load, TA = 25°C

1.5

4

mA

Table 5.

Transmitter electrical characteristics

(C1 - C4 = 0.1 µF, VCC = 5V ± 10 %, TA = -40 to 85 °C, unless otherwise specified. Typical

values are referred to TA = 25 °C).

Symbol

Parameter

Test condition

Min.

Typ.

Max.

Unit

VTOUT

Output voltage swing

All transmitter outputs are loaded

± 5

± 9

V

with 3kΩ to GND

ITIL

Logic pull-up current

TIN = 0V

5

40

µA

VTIL

Input logic threshold low

0.8

1.4

V

VTIH

Input logic threshold high

1.4

2

V

SRT

Transition slew rate

TA = 25°C, VCC = 5V

6

12

30

V/µs

R = 3 to 7kΩ, C

L

= 50 to 2500pF (1)

L

DR

Data rate

(2)

200

400

kbits/s

RTOUT

Transmitter output resistance

VCC = V+ = V- = 0V VOUT = ± 2V

300

Ω

ISC

Transmitter output short circuit

One TXOUT to GND

±7

±22

mA

current

tDT

Propagation delay time

TTL-CMOS IN to RS-232 OUT

1.3

3.5

µs

CL = 150pF (50% to 50%)

1.Measured from 3 V to -3 V or from -3 V to 3 V.

2.One transmitter output is loaded with RL = 3 kΩ to 7 kΩ, CL = 50 to 1000 pF.

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