Datasheet MAX3318EEUP, MAX3318EEAP, MAX3317EEUP, MAX3317EEAP, MAX3317ECUP Datasheet (Maxim)

_______________General Description

The MAX3316E–MAX3319E are 2.5V powered RS-232
compatible transceivers. These devices feature shut­down (MAX3317E), AutoShutdown Plus™ (MAX3318E/
MAX3319E), and enhanced electrostatic discharge
(ESD) protection integrated into the chip. All transmitter
outputs and receiver inputs are protected to ±15kV
using the IEC 1000-4-2 Air-Gap Discharge method,
±8kV using the IEC 1000-4-2 Contact Discharge
method, and ±15kV using the Human Body Model.

All devices are guaranteed at a data rate of 460kbps.
The transceivers have a proprietary low-dropout trans­mitter output stage enabling RS-232 compatible opera­tion from a +2.25V to +3.0V supply with a dual charge
pump. The charge pump requires only four 0.1µF
capacitors. The MAX3318E/MAX3319E feature a logic­level output (READY) that asserts when the charge
pump is regulating and the device is ready to begin
transmitting.

The MAX3318E/MAX3319E achieve a 1µA supply current
using Maxim’s revolutionary AutoShutdown Plus feature.
These devices automatically enter a low-power shut­down mode when the RS-232 cable is disconnected or
the transmitters of the connected peripherals are inactive
for more than 30 seconds. They turn on again when
they sense a valid transition at any transmitter or receiver
input. AutoShutdown Plus saves power without
changes to the existing BIOS or operating system. The
MAX3317E also features a 1µA shutdown mode that
can be entered by driving SHDN low. The MAX3317E’s
receivers remain active while in shutdown mode, allowing
external devices such as modems to be monitored
using only 1µA supply current.

These devices are available in space-saving packages:
MAX3316E (16-pin SSOP and 20-pin TSSOP), MAX3317E/
MAX3318E (20-pin SSOP and 20-pin TSSOP), and
MAX3319E (16-pin SSOP).

________________________Applications

Palmtop Computers

Hand-Held Instruments

Pagers

Cellular Phones

GPS

Handy Terminals

Hand-Held Electronic Books

____________________________Features

♦ ESD Protection for RS-232 I/O Pins

±15kV—Human Body Model
±8kV—IEC 1000-4-2, Contact Discharge
±15kV—IEC 1000-4-2, Air-Gap Discharge

♦ 300µA Operating Supply Current

♦ 1µA Low-Power Shutdown with Receivers Active

♦ Guaranteed 460kbps Data Rate

♦ Guaranteed 4V/µs Slew Rate

♦ RS-232 Compatible Down to 2.25V

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,

RS-232 Compatible Transceivers

________________________________________________________________ Maxim Integrated Products 1

Pin Configurations

19-1616; Rev 0; 1/00

For free samples and the latest literature, visit www.maxim-ic.com or phone [phone].
For small orders, phone [phone].

Ordering Information

Selector Guide and Typical Application Circuits appear at
end of data sheet.

AutoShutdown Plus is a trademark of Maxim Integrated Products.

PART

MAX3316ECUP

0°C to +70°C

TEMP. RANGE PIN-PACKAGE

20 TSSOP

MAX3316ECAE 0°C to +70°C 16 SSOP

MAX3316EEUP -40°C to +85°C 20 TSSOP

MAX3316EEAE -40°C to +85°C 16 SSOP

MAX3317ECUP

0°C to +70°C 20 TSSOP

MAX3317ECAP 0°C to +70°C 20 SSOP

MAX3317EEUP -40°C to +85°C 20 TSSOP

MAX3317EEAP -40°C to +85°C 20 SSOP

MAX3318ECUP

0°C to +70°C 20 TSSOP

MAX3318ECAP 0°C to +70°C 20 SSOP

MAX3318EEUP -40°C to +85°C 20 TSSOP

MAX3318EEAP -40°C to +85°C 20 SSOP

MAX3319ECAE

0°C to +70°C 16 SSOP

MAX3319EEAE -40°C to +85°C 16 SSOP

Pin Configurations continued at end of data sheet.

1

READY

2

C1+

3

V+

4

MAX3318E

5

C2+

6

C2-

7

V-

8

9

R2IN

10

SSOP/TSSOP

20

19

18

17

16

15

14

13

12

11

FORCEOFF

V

CC

GND

T1OUTC1-

R1IN

R1OUT

FORCEON

T1INT2OUT

T2IN

INVALIDR2OUT

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,
RS-232 Compatible Transceivers

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC= +2.25V to +3.0V, C1–C4 = 0.1µF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at VCC= +2.5V,

T

A

= +25°C.)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

VCCto GND..............................................................-0.3V to +6V

V+ to GND (Note 1) ..................................................-0.3V to +7V

V- to GND (Note 1) ...................................................-7V to +0.3V

V+ + |V-| (Note 1) .................................................................+13V

Input Voltages

T_IN, EN, SHDN, FORCEON,

FORCEOFF to GND ...............................................-0.3V to +6V

R_IN to GND ..................................................................±25V

Output Voltages

T_OUT to GND............................................................±13.2V

R_OUT, INVALID, READY to GND .......-0.3V to (V

CC

+ 0.3V)

Short-Circuit Duration, T_OUT to GND.......................Continuous

Continuous Power Dissipation (T

A

= +70°C)

16-Pin SSOP (derate 7.14mW/°C above +70°C) .......571mW

20-Pin SSOP (derate 8.00mW/°C above +70°C) .......640mW

20-Pin TSSOP (derate 7.00mW/°C above +70°C) .....559mW

Operating Temperature Range

MAX331_EC_ _ .................................................0°C to +70°C

MAX331_EE_ _ ..............................................-40°C to +85°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

Note 1: V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.

SHDN = GND (MAX3317E); FORCEOFF =
GND (MAX3318E/MAX3319E)

All transmitter outputs loaded with 3kΩ to
ground

FORCEON = GND, FORCEOFF = VCC,
all R_IN idle, all T_IN idle
(MAX3318E/MAX3319E)

TA= +25°C

TA= +25°C

TA= +25°C

EN = VCC(MAX3317E), receivers disabled

T_IN, EN, SHDN, FORCEON, FORCEOFF

SHDN = VCC, no load (MAX3317E);
FORCEON = FORCEOFF = V

CC

, no load

(MAX3318E/MAX3319E)

T_IN, EN, SHDN, FORCEON, FORCEOFF

I

OUT

= -0.5mA

T_IN, EN, SHDN, FORCEON, FORCEOFF

I

OUT

= 0.5mA

CONDITIONS

V

±3.7 ±4

Output Voltage Swing

kΩ

357

Input Resistance

V0.3Input Hysteresis

V

0.7 · V

CC

Input Threshold High

V

0.3 · V

CC

Input Threshold Low

V

-25 +25

Input Voltage Range

V

0.9 · V

CC

Output Voltage High

V

0.1 · V

CC

Output Voltage Low

µA

110

Shutdown Supply Current

µA

110

AutoShutdown Plus Supply
Current

µA

±0.05 ±10

Output Leakage Current

µA

±0.01 ±1

Input Leakage Current

V

0.3

Transmitter Input Hysteresis

mA

0.3 1

Supply Current

V

0.3 · V

CC

Input Logic Threshold Low

V

0.7 · V

CC

Input Logic Threshold High

UNITSMIN TYP MAXSYMBOL

LOGIC INPUTS

RECEIVER OUTPUTS

RECEIVER INPUTS

MAX3316E–MAX3319E

PARAMETER

DC CHARACTERISTICS (VCC= +2.5V, TA= +25°C)

TRANSMITTER OUTPUTS

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,

RS-232 Compatible Transceivers

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(VCC= +2.25V to +3.0V, C1–C4 = 0.1µF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at VCC= +2.5V,

T

A

= +25°C.)

TIMING CHARACTERISTICS

(VCC= +2.25V to +3.0V, C1–C4 = 0.1µF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at VCC= +2.5V,

T

A

= +25°C.)

VCC= 0 or 2.25V to 3.0V, V

OUT

= ±12V,

transmitters disabled

VCC= 0, transmitter output = ±2V

CONDITIONS

µA

±25

Output Leakage Current

mA

±25 ±60

Output Short-Circuit Current

Ω

300 10M

Output Resistance

UNITSMIN TYP MAXSYMBOLPARAMETER

VCC= 2.5V, Figure 4b

I

OUT

= -0.5mA

I

OUT

= 0.5mA

Figure 4a

Figure 4a

µs

1

t

INVH

Receiver Positive or Negative
Threshold to INVALID High

V

0.9 · V

CC

INVALID, READY Output
Voltage High

V

0.1 · V

CC

INVALID, READY Output
Voltage Low

V

-0.3 0.3

Receiver Input Threshold to
INVALID Output Low

-2.7

V

2.7

Receiver Input Threshold to
INVALID Output High

Positive threshold

VCC= 2.5V, Figure 4b (Note 2)

VCC= 2.5V, Figure 4b (Note 2)

VCC= 2.5V, Figure 4b

Negative threshold

s

15 30 60

t

AUTO­SHDN

Receiver or Transmitter Edge to
Transmitters Shutdown

µs

100

t

WU

Receiver or Transmitter Edge to
Transmitters Enabled

µs

30

t

INVL

Receiver Positive or Negative
Threshold to INVALID Low

R_IN to R_OUT, CL= 150pF

RL= 3kΩ, CL= 1000pF, one transmitter
switching

Normal operation (MAX3317E)

Normal operation (MAX3317E)

(Note 3)

CONDITIONS

0.175

t

PLH

µs

0.175

t

PHL

kbps

460

Maximum Data Rate

Receiver Propagation Delay

ns

250

Receiver Output Enable Time

ns

250

Receiver Output Disable Time

ns

100

|t

PHL

- t

PLH

|

Transmitter Skew

ns

50

|t

PHL

- t

PLH

|

Receiver Skew

UNITSMIN TYP MAXSYMBOLPARAMETER

AutoShutdown Plus (FORCEON = GND, FORCEOFF = VCC) (MAX3318E/MAX3319E)

ESD PROTECTION

R_IN, T_OUT

±15

kV

±15

±8

Human Body Model

IEC 1000-4-2 Air-Gap Discharge method

IEC 1000-4-2 Contact Discharge method

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,
RS-232 Compatible Transceivers

4 _______________________________________________________________________________________

Typical Operating Characteristics

(VCC= +2.5V, C1–C4 = 0.1µF, 460kbps data rate, all transmitters loaded with 3kΩ, TA= +25°C, unless otherwise noted.)

0

2

6

4

8

10

2.25 2.652.45 2.85 3.05 3.25 3.45 3.65

MAX3316E/MAX3317E

SUPPLY CURRENT vs. SUPPLY VOLTAGE

MAX3316E TOC01

VCC (V)

SUPPLY CURRENT (mA)

T1 TRANSMITTING AT SPECIFIED
DATA RATE
T2 TRANSMITTING AT 20kbps
C

L

= 1000pF

460kbps

230kbps

20kbps

-6

-2

-4

2

0

4

6

2.25 2.85 3.052.45 2.65 3.25 3.45 3.65

MAX3316E/MAX3317E

TRANSMITTER OUTPUT VOLTAGE

vs. SUPPLY VOLTAGE

MAX3316E TOC02

VCC (V)

TRANSMITTER OUTPUT VOLTAGE (V)

T_OUT+

T_OUT-

T1 TRANSMITTING AT 460kbps
T2 TRANSMITTING AT 20kbps
C

L

= 1000pF

-5

-2

-3

-4

-1

0

1

2

3

4

5

0 1000 2000 3000

MAX3316E/MAX3317E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

MAX3316E TOC03

LOAD CAPACITANCE (pF)

TRANSMITTER OUTPUT VOLTAGE (V)

T_OUT+

T_OUT-

T1 TRANSMITTING AT 460kbps
T2 TRANSMITTING AT 20kbps

0

2

6

4

8

10

MAX3316E/MAX3317E

SLEW RATE vs. LOAD CAPACITANCE

MAX3316E TOC04

LOAD CAPACITANCE (pF)

SLEW RATE (V/µs)

0 20001000 3000

-SLEW

+SLEW

FOR DATA RATES UP TO 460kps

TIMING CHARACTERISTICS (continued)

(VCC= +2.25V to +3.0V, C1–C4 = 0.1µF, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at VCC= +2.5V,

T

A

= +25°C.)

Note 2: A transmitter/receiver edge is defined as a transition through the transmitter/receiver input logic thresholds.
Note 3: Transmitter skew is measured at the transmitter zero crosspoints.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

V/µs

430

VCC= 2.5V, TA= +25°C, RL= 3kΩ to 7kΩ,
measured from +3V to -3V or -3V to +3V,
C

L

= 150pF to 2500pF

Transition-Region Slew Rate

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,

RS-232 Compatible Transceivers

_______________________________________________________________________________________ 5

Typical Operating Characteristics (continued)

(VCC= +2.5V, C1–C4 = 0.1µF, 460kbps data rate, all transmitters loaded with 3kΩ, TA= +25°C, unless otherwise noted.)

0

10

5

20

15

30

25

35

MAX3316E/MAX3317E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

MAX3316E TOC05

LOAD CAPACITANCE (pF)

SUPPLY CURRENT (mA)

0 1000 2000 3000

T1 TRANSMITTING AT SPECIFIED DATA RATE
T2 TRANSMITTING AT 20kbps

460kbps

230kbps

20kbps

MAX3318E/MAX3319E

TRANSMITTER OUTPUT VOLTAGE

vs. SUPPLY VOLTAGE

T_OUT+

T1 TRANSMITTING AT 460kbps
T2 TRANSMITTING AT 20kbps

= 1000pF

C

L

T_OUT-

2.25 2.85 3.052.45 2.65 3.25 3.45 3.65
VCC (V)

MAX3318E/MAX3319E

OPERATING SUPPLY CURRENT

vs. LOAD CAPACITANCE

T1 TRANSMITTING AT SPECIFIED
DATA RATE
T2 TRANSMITTING AT 20kbps

460kbps

230kbps

20kbps

0 1000 2000 3000

LOAD CAPACITANCE (pF)

MAX3318E/MAX3319E

TRANSMITTER OUTPUT VOLTAGE

vs. LOAD CAPACITANCE

5

4

3

2

T1 TRANSMITTING AT 460kbps

1

T2 TRANSMITTING AT 20kbps

0

-1

-2

-3

TRANSMITTER OUTPUT VOLTAGE (V)

-4

-5
0 1000 2000 3000

T_OUT+

T_OUT-

LOAD CAPACITANCE (pF)

15

12

9

6

SUPPLY CURRENT (mA)

3

0

10

8

MAX3316E TOC08

6

4

SLEW RATE (V/µs)

2

0

MAX3318E/MAX3319E

SUPPLY CURRENT vs. SUPPLY VOLTAGE

460kbps

230kbps

20kbps

T1 TRANSMITTING AT SPECIFIED
DATA RATE
T2 TRANSMITTING AT 20kbps

= 1000pF

C

L

2.25 2.652.45 2.85 3.05 3.25 3.45 3.65
VCC (V)

MAX3318E/MAX3319E

SLEW RATE vs. LOAD CAPACITANCE

-SLEW

+SLEW

FOR DATA RATES UP TO 460kbs

0 20001000 3000

LOAD CAPACITANCE (pF)

6

MAX3316E TOC06

MAX3316E TOC09

4

2

0

-2

-4

TRANSMITTER OUTPUT VOLTAGE (V)

-6

35

30

25

20

15

SUPPLY CURRENT (mA)

10

5

0

MAX3316E TOC07

MAX3316E TOC10

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,
RS-232 Compatible Transceivers

6 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(VCC= +2.5V, C1–C4 = 0.1µF, 460kbps data rate, all transmitters loaded with 3kΩ, TA= +25°C, unless otherwise noted.)

Pin Description

—

—

MAX3318E

2

3

4

8, 17

7

6

5

19

18

12, 13

10, 15

9, 16

No Connection

Receiver Enable, Active Low

FUNCTION

Positive Terminal of Voltage-Doubler Charge­Pump Capacitor

+2 · VCCGenerated by the Charge Pump

Negative Terminal of Voltage-Doubler Charge­Pump Capacitor

RS-232 Transmitter Outputs

-2 · VCCGenerated by the Charge Pump

Negative Terminal of Inverting Charge-Pump
Capacitor

Positive Terminal of Inverting Charge-Pump
Capacitor

+2.25V to +3.0V Single-Supply Voltage

Ground

CMOS Transmitter Inputs

CMOS Receiver Outputs

RS-232 Receiver Inputs

—

—

MAX3319E

2

3

4

13

7

6

5

15

14

11

9

8

N.C.

EN

NAME

C1+

V+

C1-

T_OUT

V-

C2-

C2+

V

CC

GND

T_IN

R_OUT

R_IN

— 1, 10, 11, 20 11, 14

— 1

MAX3316E

MAX3317E

1 2 2

PIN

2 3 3

3 4 4

7, 14 8, 17 8, 17

6 7 7

5 6 6

4 5 5

16 19 19

15 18 18

10, 11 13, 14 12, 13

9, 12 12, 15 10, 15

8, 13 9, 16 9, 16

SSOP TSSOP

MAX3318E/MAX3319E
READY TURN-OFF TIME

vs. TEMPERATURE

TRANSMITTER SKEW vs.

LOAD CAPACITANCE (t

500

T1 TRANSMITTING AT 460kbps
T2 TRANSMITTING AT 20kbps

400

300

200

TRANSMITTER SKEW (ns)

100

- t

PLH

MAX3316E/MAX3317E

MAX3318E/MAX3319E

PHL

)

MAX3316E TOC11

MAX3318E/MAX3319E
READY TURN-ON TIME

vs. TEMPERATURE

30

25

20

15

10

READY TURN-ON TIME (µs)

5

200

160

MAX3316E TOC12

120

80

READY TURN-OFF TIME (ns)

40

MAX3316E TOC13

0

0 1000500 1500 2000 2500 3000

LOAD CAPACITANCE (pF)

0

-40 0 20-20 40 60 80
TEMPERATURE (°C)

0

-40 0-20 20 40 60 80
TEMPERATURE (°C)

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,

RS-232 Compatible Transceivers

_______________________________________________________________________________________ 7

Pin Description (continued)

Detailed Description

Dual Charge-Pump Voltage Converter

The MAX3316E–MAX3319Es’ internal power supply
consists of a regulated dual charge pump that provides
output voltages of +4.4V (doubling charge pump) and

-4.3V (inverting charge pump), over the +2.25V to
+3.0V range. The charge pump operates in discontinu­ous mode: if the output voltages are less than 4.4V, the
charge pump is enabled; if the output voltages exceed

4.4V, the charge pump is disabled. Each charge pump
requires a flying capacitor (C1, C2) and a reservoir
capacitor (C3, C4) to generate the V+ and V- supplies.

The READY output (MAX3318E/MAX3319E) is low
when the charge pumps are disabled in shutdown
mode. The READY signal asserts high when V- goes
below -2.75V.

RS-232 Compatible Transmitters

The MAX3316E–MAX3319Es’ transmitters are inverting
level translators that convert CMOS-logic levels to
RS-232 compatible voltage levels. They guarantee a
460kbps data rate with worst-case loads of 3kΩ in parallel
with 1000pF, providing compatibility with PC-to-PC
communication software (such as LapLink™).

The MAX3317E’s transmitters are turned off (high
impedance) when SHDN is asserted low, putting the
device in shutdown mode. The MAX3318E/MAX3319Es’

transmitters are turned off (high impedance) when
FORCEOFF is asserted low, or when the AutoShutdown
Plus circuitry senses that all receiver and transmitter
inputs are inactive for more than 30 seconds.

The transmitter outputs can be driven to ±12V when
power is off. The transmitter inputs do not have internal
pull-up resistors. Connect unused inputs to GND or VCC.

RS-232 Receivers

The MAX3316E–MAX3319Es’ receivers convert ±3.7V
to ±13.2V RS-232 signal levels into CMOS-logic output
levels. The receivers are rated to receive signals up to
±25V. The MAX3316E/MAX3318E/MAX3319Es’
receivers feature inverting outputs that always remain
active (Table 1). The MAX3317E’s receivers have
inverting, three-state outputs. In shutdown, the
receivers can be active or inactive (Table 2).

The MAX3318E/MAX3319E feature an INVALID output
that is asserted low when no valid RS-232 voltage levels
have been detected on all receiver inputs. Because
INVALID indicates the receiver’s input condition, it
is independent of the states of FORCEON and
FORCEOFF.

MAX3317E Shutdown Mode

Supply current falls to less than 1µA in shutdown mode
(SHDN = low). When shut down, the device’s charge
pumps are turned off, V+ is pulled down to V

CC

, V- is
pulled to ground, and the transmitter outputs are dis­abled (high impedance). The time required to exit shut-

LapLink is a trademark of Traveling Software.

PIN

MAX3316E

MAX3317E MAX3318E MAX3319E

NAME FUNCTION

Shutdown Control, Active Low

Ready to Transmit Output, Active High. READY is
enabled high when V- goes below -3.5V and the
device is ready to transmit.

Valid Signal Detector Output, Active Low. A logic
high indicates that a valid RS-232 level is present
on a receiver input.

Force-On Input, Active High. Drive high to override
AutoShutdown Plus, keeping transmitters and
receivers on (FORCEOFF must be high) (Table 1).

Force-Off Input, Active Low. Drive low to shut
down transmitters, receivers, and charge pump.
This overrides AutoShutdown Plus and FORCEON
(Table 1).

FORCEOFF

FORCEON

INVALID

READY

SHDN

—

1

10

12

1620

14

11

1

—20

—

—

—

—

—

—

—

—

—

SSOP TSSOP

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,
RS-232 Compatible Transceivers

8 _______________________________________________________________________________________

down is typically 30µs, as shown in Figure 2. Connect
SHDN to VCCif the shutdown mode is not used; SHDN
has no effect on R_OUT.

MAX3318E/MAX3319E

AutoShutdown Plus Mode

Maxim’s AutoShutdown Plus feature on the MAX3318E/
MAX3319E allows the supply current to fall to 1µA.
These devices will enter the AutoShutdown Plus mode if
FORCEOFF is high, FORCEON is low, and they do not

sense a valid signal transition on any receiver or trans­mitter input for 30 seconds. This may occur if the RS-232
cable is disconnected or if the peripheral transmitters
are turned off, and the UART driving the transmitter
inputs is inactive. The system turns on again when a
valid transition is applied to any RS-232 receiver or
transmitter input. As a result, the system saves power
without changes to the existing BIOS or operating system.

Figure 4a depicts valid and invalid RS-232 receiver volt­age levels. INVALID indicates the receiver input’s condi­tion and is independent of FORCEON and FORCEOFF
states. Figure 3 and Table 1 summarize the operating
modes of the MAX3318E/MAX3319E. FORCEON and
FORCEOFF override AutoShutdown Plus circuitry. When
neither control is asserted, the IC selects between these
states automatically based on the last receiver or trans­mitter edge received.

When shut down, the device’s charge pumps turn off,
V+ is pulled to V

CC

, V- is pulled to ground, the transmitter
outputs are high impedance, and READY is driven low.
The time required to exit shutdown is typically 30µs
(Figure 2).

X

X

X

X

VALID RECEIVER

LEVEL

Active

Active

Active

Active

R_OUT

No

Yes

X

X

RECEIVER OR

TRANSMITTER

EDGE WITHIN

30s

High-Z

Active

Active

High-Z

T_OUT

Shutdown
(AutoShutdown Plus)

0 1

Normal Operation
(AutoShutdown Plus)

0 1

Normal Operation
(Forced On)

1 1

Shutdown (Forced
Off)

X 0

OPERATION

STATUS

FORCEON

FORCEOFF

No

Yes

No

X

Yes

Active

Active

Active

Active

Active

X

X

No

Yes

X

High-Z

Active

High-Z

Active

Active

Shutdown
(AutoShutdown)

INVALID** INVALID**

Normal Operation
(AutoShutdown)

INVALID** INVALID**

Shutdown

INVALID*

1

Normal Operation

INVALID*

1

Normal Operation

INVALID*

1

Table 1. Output Control Truth Table (MAX3318E/MAX3319E)

Table 2. Shutdown and Enable Control
Truth Table (MAX3317E)

X = Don’t care

*

INVALID

connected to FORCEON

**

INVALID

connected to FORCEON and

FORCEOFF

SHDN EN

T_OUT R_OUT

0 0 High-Z Active

0 1 High-Z High-Z

1 0 Active Active

1 1 Active High-Z

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,

RS-232 Compatible Transceivers

_______________________________________________________________________________________ 9

Figure 1a. RS-232 Compatibility Circuit

Figure 1b. MAX3316E–MAX3319E Transmitter Output
Compatibility with an RS-232 Receiver

Figure 2. Transmitter Outputs when Exiting Shutdown or
Powering Up

+2.5V

C1+

C1-

C2+

C2-

0.1µF

MAX3316E
MAX3317E
MAX3318E
MAX3319E

V

CC

V+

V-

C4

0.1µF

C3

0.1µF

+5V

0.1µF

0.1µF

C

BYPASS

C1

C2

T_ IN

R_ OUT

5V/div

5V/div

5V/div

T_ OUT

R_ IN

GND

T1 IN
MAX3316E–MAX3319E

T1 OUT
MAX3316E–MAX3319E

RS-232 COMPLIANT
RECEIVER OUTPUT

1000pF

2V/div

2V/div

RX

RS-232

COMPLIANT

TX

TRANSCEIVER

VCC OR SHDN
(MAX3317E)

FORCEOFF
(MAX3318E/MAX3319E)

T1

T2

10µs/div

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,
RS-232 Compatible Transceivers

10 ______________________________________________________________________________________

By connecting FORCEON to INVALID, the MAX3318E/
MAX3319E shut down when no valid receiver level is
detected and wake up when a valid receiver level is
detected.

A system with AutoShutdown Plus may need time to
wake up. Figure 5 shows a circuit that forces the trans­mitters on for 100ms, allowing enough time for the other
system to realize that the MAX3318E/MAX3319E is
awake. If the other system outputs valid RS-232 signal
transitions within that time, the RS-232 ports on both
systems remain enabled.

Connecting to the PC

(MAX3318E/MAX3319E)

If direct software control is desired, use INVALID to
indicate DTR or ring indicator (RI) signal. This can be
used to connect a hand-held device to a PC. One
example is using the Hot Sync™ function on a personal
digital assistant (PDA). The transmitter and receiver
signals (T_OUT and R_IN) are used for communication,
while INVALID causes a change of state on RI. The
change of state on RI will trigger an interrupt on the PC
and allow communication to begin between the device
and the PC. This eliminates the need for the PC to poll
constantly the receiver or transmitter lines to determine
if the device is connected.

±15kV ESD Protection

All the pins on the MAX3316E–MAX3319E are protect­ed against ESDs encountered during handling and
assembly. The driver outputs and receiver inputs have
extra protection against static electricity. Maxim’s engi­neers have developed state-of-the-art structures to pro­tect these pins against ESD of ±15kV without damage.
The ESD structures withstand high ESD in all states:
normal operation, shutdown, and powered down. After
an ESD event, Maxim’s E versions keep working without
latchup, whereas competing products can latch and
must be powered down to remove latchup.

ESD protection can be tested in various ways; the trans­mitter outputs and receiver inputs of the product family
are characterized for protection to the following limits:

• ±15kV using the Human Body Model

• ±8kV using the IEC 1000-4-2 Contact Discharge
method

• ±15kV using IEC 1000-4-2 Air-Gap method

ESD Test Conditions

ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents
test setup, test methodology, and test results.

Human Body Model

Figure 6a shows the Human Body Model, and Figure 6b
shows the current waveform it generates when dis­charged into low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which is then discharged into the test device through a

1.5kΩ resistor.

Figure 3a.

INVALID

Functional Diagram,

INVALID

Low

Figure 3b.

INVALID

Functional Diagram,

INVALID

High

Figure 4a. Receiver Positive/Negative Thresholds for

INVALID

Hot Sync is a trademark of 3Com.

+0.3V

R_IN

-0.3V

INVALID ASSERTED IF ALL RECEIVER INPUTS ARE BETWEEN +0.3V AND -0.3V FOR
AT LEAST 30µs.

+2.7V

R_IN

-2.7V

INVALID DEASSERTED IF ANY RECEIVER INPUT HAS BEEN BETWEEN +2.7V AND -2.7V
FOR LESS THAN 30µs.

+2.7V

+0.3V

0

-0.3V

RECEIVER INPUT LEVELS

-2.7V

INVALID HIGH

INDETERMINATE

INVALID LOW

INDETERMINATE

INVALID HIGH

30µs

TIMER

R

30µs

TIMER

R

INVALID

INVALID

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,

RS-232 Compatible Transceivers

______________________________________________________________________________________ 11

Figure 5. AutoShutdown Plus Initial Turn-On to Wake Up a
Mouse or Another System

Figure 6a. Human Body ESD Test Model

Figure 4b. AutoShutdown Plus,

INVALID

, and READY Timing Diagram

RECEIVER

INPUTS

TRANSMITTER

INPUTS

TRANSMITTER

OUTPUTS

V

INVALID
OUTPUT

OUTPUT

MAX3318E/MAX3319E

CC

0

*V

CC

0

V+

V

CC

0

V-

t

INVL

t

INVH

t

AUTOSHDN

INVALID

}

REGION

t

t

WU

AUTOSHDN

t

WU

POWER-

MANAGEMENT

UNIT

MASTER SHDN LINE

0.1µF 1M

FORCEOFF

FORCEON

MAX3318E
MAX3319E

HIGH-

VOLTAGE

DC

SOURCE

R

C

1M

CHARGE-CURRENT

LIMIT RESISTOR

C

100pF

s

R

D

1500Ω

DISCHARGE

RESISTANCE

STORAGE
CAPACITOR

DEVICE
UNDER

TEST

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,
RS-232 Compatible Transceivers

12 ______________________________________________________________________________________

IEC 1000-4-2

The IEC 1000-4-2 standard covers ESD testing and
performance of finished equipment; it does not specifi­cally refer to ICs. The MAX3316E–MAX3319E help you
design equipment that meets Level 4 (the highest level)
of IEC 1000-4-2 without the need for additional ESD­protection components.

The major difference between tests done using the
Human Body Model and IEC 1000-4-2 is higher peak
current in IEC 1000-4-2 because series resistance is
lower in the IEC 1000-4-2 model. Hence, the ESD with­stand voltage measured to IEC 1000-4-2 is generally
lower than that measured using the Human Body
Model. Figure 7a shows the IEC 1000-4-2 model, and
Figure 7b shows the current waveform for the 8kV, IEC
1000-4-2, Level 4, ESD Contact Discharge test.

The Air-Gap Discharge test involves approaching the
device with a charged probe. The Contact Discharge
method connects the probe to the device before the
probe is energized.

Machine Model

The Machine Model for ESD tests all pins using a
200pF storage capacitor and zero discharge resis­tance. Its objective is to emulate the stress caused by
contact that occurs with handling and assembly during
manufacturing. All pins require this protection during
manufacturing, not just RS-232 inputs and outputs.
Therefore, after PC board assembly, the Machine Model
is less relevant to I/O ports.

Applications Information

RS-232 Compatible Operation

The MAX3316E–MAX3319E do not meet EIA-232
requirements for transmitter output voltage levels. EIA-232
compliance specifies transmitter output voltage swings
of ±5V when loaded with 3kΩ and 2500pF.

The receiver inputs are fully EIA-232 compliant.

The MAX3316E–MAX3319E will function properly with
most modern RS-232 interfaces. This allows RS-232
compatible communication in low-voltage systems without
the added expense of a voltage tripler or switched­mode power supply.

Figure 6b. Human Body Current Waveform

Figure 7a. IEC 1000-4-2 ESD Test Model

Figure 7b. IEC 1000-4-2 ESD Generator Current Waveform

IP 100%

90%

AMPERES

36.8%

10%

0

0

t

RL

R

C

50M to 100M

CHARGE-CURRENT

LIMIT RESISTOR

HIGH-

VOLTAGE

DC

SOURCE

150pF

C

s

I

r

TIME

t

DL

CURRENT WAVEFORM

RD

330Ω

DISCHARGE

RESISTANCE

STORAGE
CAPACITOR

PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)

DEVICE
UNDER

TEST

I

100%

90%

PEAK

I

10%

tr = 0.7ns to 1ns

30ns

60ns

t

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,

RS-232 Compatible Transceivers

______________________________________________________________________________________ 13

Capacitor Selection

The capacitor type used for C1–C4 is not critical for
proper operation; polarized or nonpolarized capacitors
can be used. The charge pump requires 0.1µF capaci­tors. Increasing the capacitor values (e.g., by a factor of

2) reduces ripple on the transmitter outputs and slightly
reduces power consumption. C2, C3, and C4 can be
increased without changing C1’s value. However, do

not increase C1 without also increasing the values of
C2, C3, C4, and C

BYPASS

to maintain proper ratios

(C1 to other capacitors).

When using the minimum-required capacitor values,
make sure the capacitor value does not degrade exces­sively with temperature. If in doubt, use capacitors with
a higher nominal value. The capacitor’s equivalent
series resistance (ESR), which usually rises at low tem­peratures, influences the amount of ripple on V+ and V-.

Power-Supply Decoupling

In most circumstances, a 0.1µF bypass capacitor is
adequate. In applications that are sensitive to power­supply noise, decouple VCCto ground with a capacitor
of the same value as charge pump capacitor C1.
Connect bypass capacitors as close to the IC as possible.

Transmitter Outputs when

Exiting Shutdown

Figure 2 shows two transmitter outputs when exiting
shutdown mode. As they become active, the two trans­mitter outputs are shown going to opposite RS-232 com­patible levels (one transmitter input is high, the other is
low). Each transmitter is loaded with 3kΩ in parallel with
2500pF. The transmitter outputs display no ringing or
undesirable transients as they come out of shutdown.
Note that the transmitters are enabled only when the
magnitude of V- exceeds approximately -3V.

High Data Rates

The MAX3316E–MAX3319E maintain RS-232 compatible
±3.7V minimum transmitter output voltage even at high
data rates. Figure 8 shows a transmitter loopback test
circuit. Figure 9 shows a loopback test result at
230kbps. For Figure 9, all transmitters were driven
simultaneously at 230kbps into EIA/TIA-562 loads in
parallel with 1000pF.

Chip Information

TRANSISTOR COUNT: 1130

Figure 8. Loopback Test Circuit

Figure 9. Loopback Test Result at 230kbps

V

CC

C

BYPASS

C1+

C1

C2

V

CC

*C3 CAN BE RETURNED TO VCC OR GND.
**MAX3318E/MAX3319E

2V/div

5V/div

2V/div

C1-

C2+

C2-

T_ IN

R_ OUT

FORCEON**

FORCEOFF**

MAX3316E
MAX3317E
MAX3318E
MAX3319E

V

GND

CC

V+

V-

T_ OUT

R_ IN

5k

C3*

C4

1000pF

T1 IN

T1 OUT

R1 OUT

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,
RS-232 Compatible Transceivers

14 ______________________________________________________________________________________

Pin Configurations (continued)

TOP VIEW

20

19

18

17

16

15

14

13

12

11

1

C1+ V

V+

2

C1-

3

MAX3316E

4

C2+

C2-

5

V-

6

T2OUT

7

R2IN

8

SSOP

1

N.C.

2

C1+

3

CC

GND

T1OUT

R1IN

R1OUT

T1IN

T2IN

R2OUT

C2+

C2-

R2IN

V+

4

MAX3316E

5

6

7

V-

8

9

10

16

15

14

13

12

11

10

9

TSSOP

N.C.

V

CC

GND

T1OUTC1-

R1IN

R1OUT

T1IN

T2INT2OUT

R2OUT

N.C.N.C.

EN

C1+

V+

C2+

C2-

V-

R2IN

1

2

3

4

MAX3317E

5

6

7

8

9

10

SSOP/TSSOP

20

SHDN

19

V

CC

GND

18

T1OUTC1-

17

R1IN

16

R1OUT

15

14

N.C.

T1INT2OUT

13

12

T2IN

11

N.C.R2OUT

1

READY FORCEOFF

C1+

2

V+

3

MAX3319E

4

C1-

C2+

5

C2-

6

V-

7

R1IN

8

16

15

14

13

12

11

10

9

V

CC

GND

T1OUT

FORCEON

T1IN

INVALID

R1OUT

SSOP

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,

RS-232 Compatible Transceivers

______________________________________________________________________________________ 15

Typical Application Circuits

Selector Guide

PART

NO. OF DRIVERS/

RECEIVERS

GUARANTEED

DATA RATE (kbps)

READY OUTPUT SHUTDOWN

AutoShutdown

Plus

MAX3316E 2/2 460 — — —

MAX3317E 2/2 460 —

✓

—

MAX3318E 2/2 460

✓

—

✓

MAX3319E 1/1 460

✓

—

✓

Typical Application Circuits continue on next page.

0.1µF

0.1µF

C2

0.1µF

CMOS

INPUTS

C1

+2.5V

19

V

2

C1+

4

C1-

5

C2+

6

C2-

13

T1IN

T2IN

12

CC

MAX3317E

T1OUT

T2OUT

3

V+

V-

C3*

0.1µF

7

C4

0.1µF

17

RS-232
COMPATIBLE
OUTPUTS

8

0.1µF

0.1µF

0.1µF

CMOS

INPUTS

+2.5V

16

V

1

C1+

3

C1-

4

C2+

5

C2-

11

T1IN

T2IN

10

CC

MAX3316E

T1OUT

T2OUT

2

V+

V-

C3*

0.1µF

6

C4

0.1µF

14

RS-232
COMPATIBLE
OUTPUTS

7

16

OR GROUND.

CC

R1IN

5k

R2IN

5k

SHDN

9

20

CMOS

OUTPUTS

1

*C3 CAN BE RETURNED TO EITHER V

R1OUT15

R2OUT10

EN

GND

18

RS-232
COMPATIBLE
INPUTS

CMOS

OUTPUTS

R1OUT12

R2OUT9

GND

15

CIRCUIT SHOWN IS FOR THE 16-PIN SSOP.

R1IN

5k

R2IN

5k

13

RS-232
COMPATIBLE
INPUTS

8

MAX3316E–MAX3319E

±15kV ESD-Protected, 2.5V, 1µA, 460kbps,
RS-232 Compatible Transceivers

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

16 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600

© 2000 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.

Typical Application Circuits (continued)

+2.5V

C

OUTPUTS

BYPASS

C1

0.1µF

C2

0.1µF

CMOS

INPUTS

CMOS

0.1µF

2

C1+

4

C1-

5

C2+

6

C2-

13

T1IN

T2IN

12

R1OUT15

R2OUT10

READY

1

FORCEON

14

19

V

CC

MAX3318E

AutoShutdown

Plus

GND

18

T1OUT 17

T2OUT

R1IN

5k

R2IN

5k

INVALID 11

FORCEOFF

3

V+

V-

7

8

16

9

20

V

C3

0.1µF

C4

0.1µF

RS-232 COMPATIBLE
OUTPUTS

RS-232 COMPATIBLE
INPUTS

TO POWER­MANAGEMENT
UNIT

CC

C

BYPASS

C1

0.1µF

C2

0.1µF

CMOS
INPUT

CMOS

OUTPUT

+2.5V

0.1µF

12

11

2

4

5

6

1

C1+

C1-

C2+

C2-

T1IN

R1OUT9

READY

FORCEON

15

V

CC

MAX3319E

AutoShutdown

Plus

GND

14

T1OUT 13

R1IN 8

5k

INVALID 10

FORCEOFF

3

V+

V-

7

16

C3

0.1µF

C4

0.1µF

RS-232
COMPATIBLE
OUTPUT

RS-232
COMPATIBLE
INPUT

TO POWER­MANAGEMENT
UNIT

V

CC