TEXAS INSTRUMENTS MAX3318 Technical data

现货库存、技术资料、百科信息、热点资讯，精彩尽在鼎好!

www.ti.com

1 2 3 4 5 6 7 8 9 10

20 19 18 17 16 15 14 13 12 11

READY

C1+

V+ C1− C2+ C2−

V−

DOUT2

RIN2

ROUT2

FORCEOFF V

GND DOUT1 RIN1 ROUT1 FORCEON DIN1 DIN2 INVALID

DB OR PW PACKAGE

(TOP VIEW)

MAX3318

2.5-V 460-kbps RS-232 TRANSCEIVER

WITH ± 15-kV ESD PROTECTION

SLLS687 – OCTOBER 2005

FEATURES

• ESD Protection for RS-232 I/O Pins – ± 15 kV (Human-Body Model) – ± 8 kV (IEC 61000, Contact Discharge)

• Cellular Phones

• Notebooks

• Hand-Held Equipment

• Pagers

– ± 8 kV (IEC 61000, Air-Gap Discharge)

• 300- µ A Operating Supply Current

• 1- µ A Low-Power Standby (With Receivers

Active) Mode

• Designed to Transmit at a Data Rate of 460 kbps

• Auto-Power-Down Plus Option Features Flexible Power-Saving Mode

• Operates From a Single 2.25-V to 3-V V

Supply

APPLICATIONS

• Battery-Powered Systems

• PDAs

DESCRIPTION/ORDERING INFORMATION

The MAX3318 is a dual-driver, dual-receiver, RS-232 compatible transceiver. The device features auto-power-down plus and enhanced electrostatic discharge (ESD) protection integrated into the chip. Driver output and receiver input are protected to ± 8 kV using the IEC 61000 Air-Gap Discharge method, ± 8 kV using the IEC 61000 Contact Discharge method, and ± 15 kV using the Human-Body Model (HBM).

The device operates at a data rate of 460 kbps. The transceiver has a proprietary low-dropout driver output stage enabling RS-232-compatible operation from a 2.25-V to 3-V supply with a dual charge pump. The charge pump requires only four 0.1- µ F capacitors and features a logic-level output (READY) that asserts when the charge pump is regulating and the device is ready to begin transmitting.

The MAX3318 achieves a 1- µ A supply current using the auto-power-down feature. This device automatically enters a low-power power-down mode when the RS-232 cable is disconnected or the drivers of the connected peripherals are inactive for more than 30 s. The device turns on again when it senses a valid transition at any driver or receiver input. Auto power down saves power without changes to the existing BIOS or operating system.

This device is available in two space-saving packages: 20-pin SSOP and 20-pin TSSOP.

PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

www.ti.com

MAX3318

2.5-V 460-kbps RS-232 TRANSCEIVER

WITH ± 15-kV ESD PROTECTION

SLLS687 – OCTOBER 2005

ORDERING INFORMATION

SSOP – DB MA3318C

–0 ° C to 70 ° C

TSSOP – PW MA3318C

SSOP – DB MA3318I

–40 ° C to 85 ° C

TSSOP – PW MA3318I

(1) Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at

www.ti.com/sc/package.

PACKAGE

DETAILED DESCRIPTION

Flexible control options for power management are featured when the serial port and driver inputs are inactive. The auto-power-down plus feature functions when FORCEON is low and FORCEOFF is high. During this mode of operation, if the device does not sense valid signal transitions on all receiver and driver inputs for approximately 30 s, the built-in charge pump and drivers are powered down, reducing the supply current to 1 µ A. By disconnecting the serial port or placing the peripheral drivers off, auto-power-down plus can be disabled when FORCEON and FORCEOFF are high. With auto-power-down plus enabled, the device activates automatically when a valid signal is applied to any receiver or driver input. INVALID is high (valid data) if any receiver input voltage is greater than 2.7 V or less than –2.7 V, or has been between –0.3 V and 0.3 V for less than 30 µ s (typical number). INVALID is low (invalid data) if all receiver input voltage are between –0.3 V and 0.3 V for more than 30 µ s (typical number).

(1)

Tube of 70 MAX3318CDB Reel of 2000 MAX3318CDBR Tube of 70 MAX3318CPW Reel of 2000 MAX3318CPWR Tube of 70 MAX3318IDB Reel of 2000 MAX3318IDBR Tube of 70 MAX3318IPW Reel of 2000 MAX3318IPWR

ORDERABLE PART NUMBER TOP-SIDE MARKING

www.ti.com

2.5-V 460-kbps RS-232 TRANSCEIVER

WITH ± 15-kV ESD PROTECTION

SLLS687 – OCTOBER 2005

FUNCTION TABLE

INPUT CONDITIONS OUTPUT STATES

RECEIVER

FORCEON FORCEOFF LEVEL DRIVER RECEIVER INVALID READY

H H No No Active Active L H auto-power-down

H H No Yes Active Active H H auto-power-down

L H Yes No Active Active L H auto-power-down

L H Yes Yes Active Active H H auto-power-down

L H No No Z Active L L auto-power-down

L H No Yes Z Active H L auto-power-down

X L X No Z Active L L

X L X Yes Z Active H L

INVALID INVALID X No Z Active L L power down

INVALID INVALID X Yes Active Active H H auto power down

(1) H = high level, L = low level, X = irrelevant, Z = high impedance

OR DRIVER

EDGE

WITHIN 30 s

VALID

RS-232

PRESENT AT

RECEIVER Auto-Power-Down Plus Conditions

Auto-Power-Down Conditions

(1)

MAX3318

OPERATING

MODE

Normal operation, plus disabled

Normal operation, plus enabled

Power down, plus enabled

Manual power down

Power down, auto enabled

Normal operation, enabled

www.ti.com

DIN2

DIN1

DOUT2

DOUT1

Auto-Power-Down Plus

INVALID

RIN1

RIN2

FORCEOFF

FORCEON

ROUT1

ROUT2

5 k

Ω

READY

MAX3318

2.5-V 460-kbps RS-232 TRANSCEIVER

WITH ± 15-kV ESD PROTECTION

SLLS687 – OCTOBER 2005

LOGIC DIAGRAM (POSITIVE LOGIC)

www.ti.com

TERMINAL FUNCTIONS

TERMINAL

NAME NO.

C1+ 2 Positive voltage-doubler charge-pump capacitor C1– 4 Negative voltage-doubler charge-pump capacitor C2+ 5 Positive inverting charge-pump capacitor C2– 6 Negative inverting charge-pump capacitor DIN 12, 13 CMOS driver inputs DOUT 8, 17 RS-232 driver outputs

FORCEOFF 20

FORCEON 14 GND 18 Ground INVALID 11

READY 1 RIN 9, 16 RS-232 receiver inputs

ROUT 10, 15 CMOS receiver outputs V+ 3 2 × V V– 7 –2 × V V

Force-off input, active low. Drive low to power down transmitters, receivers, and charge pump. This overrides auto power down and FORCEON (see Function Table).

Force-on input, active high. Drive high to override auto power down, keeping transmitters and receivers on ( FORCEOFF must be high) (see Function Table).

Valid signal detector output, active low. A logic high indicates that a valid RS-232 level is present on a receiver input.

Ready to transmit output, active high. READY is enabled high when V– goes below –3.5 V and the device is ready to transmit.

generated by the charge pump

19 2.25-V to 3-V single-supply voltage

MAX3318

2.5-V 460-kbps RS-232 TRANSCEIVER

WITH ± 15-kV ESD PROTECTION

SLLS687 – OCTOBER 2005

DESCRIPTION

www.ti.com

MAX3318

2.5-V 460-kbps RS-232 TRANSCEIVER

WITH ± 15-kV ESD PROTECTION

SLLS687 – OCTOBER 2005

Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)

to GND –0.3 6 V

V+ to GND V– to GND V+ + IV-I

Input voltage V

Output voltage V

Short-circuit duration DOUT to GND Continuous

Continuous power dissipation (T

Storage temperature range –65 150 ° C Lead temperature (soldering, 10 s) 300 ° C

(1) Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings

(2) V+ and V– can have maximum magnitudes of 7 V, but their absolute difference cannot exceed 13 V.

(2) (2)

(2)

only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

(1)

MIN MAX UNIT

–0.3 7 V

–7 0.3 V

DIN, FORCEON, FORCEOFF to GND –0.3 6 RIN to GND ± 25 DOUT to GND ± 13.2 ROUT, INVALID, READY to GND –0.3 V

16-pin SSOP (derate 7.14 mW/ ° C above 70 ° C) 571

= 70 ° C) 20-pin SSOP (derate 8 mW/ ° C above 70 ° C 640 mW

20-pin TSSOP (derate 7 mW/ ° C above 70 ° C) 559

13 V

+ 0.3

Recommended Operating Conditions

See Figure 4

MIN NOM MAX UNIT

Supply voltage 2.25 2.5 3 V

Driver and control high-level input voltage V

Driver and control low-level input voltage V

Receiver input voltage –25 25 V

Operating free-air temperature ° C

DIN, FORCEOFF, FORCEON

= 2.5 V to 3 V 0.7 × V

= 2.5 V to 3 V 0 0.3 × V

MAX3318C 0 70 MAX3318I –40 85

5.5 V

+ 12 hidden pages