MAX3318ECUP+T [MAXIM]
Line Transceiver, 2 Func, 2 Driver, 2 Rcvr, PDSO20, TSSOP-20;
| 型号： | MAX3318ECUP+T |
| 厂家： | 
MAXIM INTEGRATED PRODUCTS |
| 描述： | Line Transceiver, 2 Func, 2 Driver, 2 Rcvr, PDSO20, TSSOP-20 光电二极管 |
| 文件： | 总16页 (文件大小：228K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
19-1616; Rev 1; 6/00
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
________________General Description
____________________________Features
The MAX3316E–MAX3319E are 2.5V powered RS-232
compatible transceivers. These devices feature shut-
down (MAX3317E), AutoShutdown Plus™ (MAX3318E/
MAX3319E), and enhanced electrostatic discharge
(ESD) protection integrated into the chip. All transmitter
outputs and receiver inputs are protected to 15ꢀV
using the IEC 1000-4-2 Air-Gap Discharge method,
8ꢀV using the IEC 1000-4-2 Contact Discharge
method, and 15ꢀV using the ꢁuman ꢂodꢃ Model.
ꢀ ESD Protection for RS-232 I/O Pins
±±15kV—Humn ꢀoꢁd ꢂoꢁeꢃ
±ꢄ5kVIEꢅ ±ꢆꢆꢆ-ꢇ-2ꢈ ꢅontmct Discꢉmrꢊe
±±15kVIEꢅ ±ꢆꢆꢆ-ꢇ-2ꢈ ꢋir-ꢌma Discꢉmrꢊe
ꢀ 3ꢆꢆµꢋ Oaermtinꢊ SHaaꢃd ꢅHrrent
ꢀ ±µꢋ Low-Power SꢉHtꢁown witꢉ Receivers ꢋctive
ꢀ ꢌHmrmnteeꢁ ꢇ6ꢆ5bas Dmtm Rmte
All devices are guaranteed at a data rate of 460ꢀbps.
The transceivers have a proprietarꢃ low-dropout trans-
mitter output stage enabling RS-232 compatible opera-
tion from a +2.25V to +3.0V supplꢃ with a dual charge
pump. The charge pump requires onlꢃ four 0.1µF
capacitors. The MAX3318E/MAX3319E feature a logic-
level output (READY) that asserts when the charge
pump is regulating and the device is readꢃ to begin
transmitting.
ꢀ ꢌHmrmnteeꢁ ꢇk/µs Sꢃew Rmte
ꢀ RS-232 ꢅouamtibꢃe Down to 2.21k
Ordering Information
PART
TEMP. RANGE
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
-40°C to +85°C
PIN-PACKAGE
20 TSSOP
16 SSOP
MAX3316ECUP
MAX3316ECAE
MAX3316EEUP
MAX3316EEAE
MAX3317ECUP
MAX3317ECAP
MAX3317EEUP
MAX3317EEAP
MAX3318ECUP
MAX3318ECAP
MAX3318EEUP
MAX3318EEAP
MAX3319ECAE
MAX3319EEAE
20 TSSOP
16 SSOP
The MAX3318E/MAX3319E achieve a 1µA supplꢃ current
using Maxim’s revolutionarꢃ AutoShutdown Plus feature.
These devices automaticallꢃ enter a low-power shut-
down mode when the RS-232 cable is disconnected or
the transmitters of the connected peripherals are inactive
for more than 30 seconds. Theꢃ turn on again when
theꢃ sense a valid transition at anꢃ transmitter or receiver
input. AutoShutdown Plus saves power without
changes to the existing ꢂIOS or operating sꢃstem. The
MAX3317E also features a 1µA shutdown mode that
can be entered bꢃ driving SHDN low. The MAX3317E’s
receivers remain active while in shutdown mode, allowing
external devices such as modems to be monitored
using onlꢃ 1µA supplꢃ current.
20 TSSOP
20 SSOP
20 TSSOP
20 SSOP
20 TSSOP
20 SSOP
20 TSSOP
20 SSOP
16 SSOP
16 SSOP
These devices are available in space-saving pacꢀages:
MAX3316E (16-pin SSOP and 20-pin TSSOP), MAX3317E/
MAX3318E (20-pin SSOP and 20-pin TSSOP), and
MAX3319E (16-pin SSOP).
-in Configurations
READY
1
2
3
4
5
6
7
8
9
20 FORCEOFF
________________________Applications
C1+
V+
19 V
CC
18 GND
Palmtop Computers
ꢁand-ꢁeld Instruments
Pagers
C1-
17 T1OUT
16 R1IN
MAX3318E
C2+
C2-
15 R1OUT
Cellular Phones
GPS
V-
14
FORCEON
T2OUT
R2IN
13 T1IN
ꢁandꢃ Terminals
ꢁand-ꢁeld Electronic ꢂooꢀs
12 T2IN
R2OUT 10
11 INVALID
Selector Guide and Typical Application Circuits appear at
end of data sheet.
AutoShutdown Plus is a trademark of Maxim Integrated Products.
SSOP/TSSOP
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
±
For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND..............................................................-0.3V to +6V
Short-Circuit Duration, T_OUT to GND.......................Continuous
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
Continuous Power Dissipation (T = +70°C)
A
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
T_IN, EN, SHDN, FORCEON,
FORCEOFF to GND ...............................................-0.3V to +6V
R_IN to GND .................................................................. 25V
Output Voltages
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
T_OUT to GND............................................................ 13.2V
R_OUT, INVALID, READY to GND .......-0.3V to (V
+ 0.3V)
CC
Note 1: V+ and V- can have maximum magnitudes of 7V, but their absolute difference cannot exceed 13V.
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.
ELECTRICAL CHARACTERISTICS
(V
= +2.25V to +3.0V, C1–C4 = 0.1µF, T = T
to T
, unless otherwise noted. Tꢃpical values are at V = +2.5V,
CC
CC
A
MIN
MAX
T
A
= +25°C.)
PARAMETER
SYMBOL
= +2.5V, T = +25°C)
CONDITIONS
MIN
TYP
MAX
UNITS
DC CHARACTERISTICS (V
CC
A
FORCEON = GND, FORCEOFF = V
all R_IN idle, all T_IN idle
(MAX3318E/MAX3319E)
,
CC
AutoShutdown Plus Supplꢃ
Current
1
1
10
10
1
µA
µA
SHDN = GND (MAX3317E); FORCEOFF =
GND (MAX3318E/MAX3319E)
Shutdown Supplꢃ Current
Supplꢃ Current
SHDN = V , no load (MAX3317E);
CC
0.3
mA
FORCEON = FORCEOFF = V , no load
CC
(MAX3318E/MAX3319E)
LOGIC INPUTS
Input Logic Threshold Low
Input Logic Threshold ꢁigh
Transmitter Input ꢁꢃsteresis
Input Leaꢀage Current
RECEIVER OUTPUTS
Output Leaꢀage Current
Output Voltage Low
V
V
T_IN, EN, SHDN, FORCEON, FORCEOFF
T_IN, EN, SHDN, FORCEON, FORCEOFF
0.3 · V
CC
0.7 · V
CC
0.3
V
0.01
1
µA
T_IN, EN, SHDN, FORCEON, FORCEOFF
0.05
10
µA
V
EN = V
(MAX3317E), receivers disabled
CC
I
= 0.5mA
= -0.5mA
0.1 · V
OUT
OUT
CC
Output Voltage ꢁigh
RECEIVER INPUTS
Input Voltage Range
Input Threshold Low
Input Threshold ꢁigh
Input ꢁꢃsteresis
I
V
0.9 · V
-25
CC
+25
V
V
T
T
= +25°C
= +25°C
0.3 · V
A
CC
V
0.7 · V
3
A
CC
0.3
5
V
Input Resistance
T
A
= +25°C
7
ꢀΩ
TRANSMITTER OUTPUTS
All transmitter outputs loaded with 3ꢀΩ to
ground
Output Voltage Swing
3.7
4
V
2
_______________________________________________________________________________________
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
ELECTRICAL CHARACTERISTICS (continued)
(V
= +2.25V to +3.0V, C1–C4 = 0.1µF, T = T
= +25°C.)
to T
, unless otherwise noted. Tꢃpical values are at V = +2.5V,
CC
CC
A
MIN
MAX
T
A
PARAMETER
SYMBOL
CONDITIONS
= 0, transmitter output = 2V
MIN
TYP
10M
25
MAX
UNITS
Ω
Output Resistance
V
V
300
CC
Output Short-Circuit Current
60
25
mA
= 0 or 2.25V to 3.0V, V
= 12V,
CC
OUT
Output Leaꢀage Current
µA
transmitters disabled
ESD PROTECTION
ꢁuman ꢂodꢃ Model
15
15
8
R_IN, T_OUT
ꢀV
IEC 1000-4-2 Air-Gap Discharge method
IEC 1000-4-2 Contact Discharge method
AutoShutdown Plus (FORCEON = GND, FORCEOFF = V ) (MAX3318E/MAX3319E)
CC
Positive threshold
Negative threshold
2.7
0.3
Receiver Input Threshold to
INVALID Output ꢁigh
Figure 4a
Figure 4a
V
V
-2.7
-0.3
Receiver Input Threshold to
INVALID Output Low
INVALID, READY Output
Voltage Low
I
I
= 0.5mA
V
0.1 · V
OUT
CC
INVALID, READY Output
Voltage ꢁigh
= -0.5mA
V
0.9 · V
OUT
CC
Receiver Positive or Negative
Threshold to INVALID ꢁigh
t
V
CC
V
CC
V
CC
V
CC
= 2.5V, Figure 4b
= 2.5V, Figure 4b
1
µs
µs
µs
s
INVꢁ
Receiver Positive or Negative
Threshold to INVALID Low
t
30
INVL
Receiver or Transmitter Edge to
Transmitters Enabled
t
= 2.5V, Figure 4b (Note 2)
= 2.5V, Figure 4b (Note 2)
100
30
WU
Receiver or Transmitter Edge to
Transmitters Shutdown
t
AUTO-
SꢁDN
15
60
TIMING CHARACTERISTICS
CC
(V
= +2.25V to +3.0V, C1–C4 = 0.1µF, T = T
to T
, unless otherwise noted. Tꢃpical values are at V = +2.5V,
CC
A
MIN
MAX
T
A
= +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
R = 3ꢀΩ, C = 1000pF, one transmitter
L
L
Maximum Data Rate
460
ꢀbps
switching
t
t
0.175
0.175
250
PꢁL
Receiver Propagation Delaꢃ
R_IN to R_OUT, C = 150pF
L
µs
PLꢁ
Receiver Output Enable Time
Receiver Output Disable Time
Transmitter Sꢀew
Normal operation (MAX3317E)
ns
ns
ns
ns
Normal operation (MAX3317E)
250
|t
|t
- t
| (Note 3)
100
PꢁL PLꢁ
Receiver Sꢀew
- t
|
50
PꢁL PLꢁ
_______________________________________________________________________________________
3
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
TIMING CHARACTERISTICS (continued)
(V
= +2.25V to +3.0V, C1–C4 = 0.1µF, T = T
to T
, unless otherwise noted. Tꢃpical values are at V = +2.5V,
CC
CC
A
MIN
MAX
T
A
= +25°C.)
PARAMETER
SYMBOL
CONDITIONS
= 2.5V, T = +25°C, R = 3ꢀΩ to 7ꢀΩ,
measured from +3V to -3V or -3V to +3V,
C = 150pF to 2500pF
MIN
TYP
MAX
UNITS
V
CC
A
L
Transition-Region Slew Rate
4
30
V/µs
L
Note 2: A transmitter/receiver edge is defined as a transition through the transmitter/receiver input logic thresholds.
Note 3: Transmitter sꢀew is measured at the transmitter zero crosspoints.
Typical Operating Characteristics
(V
= +2.5V, C1–C4 = 0.1µF, 460ꢀbps data rate, all transmitters loaded with 3ꢀΩ, T = +25°C, unless otherwise noted.)
CC
A
MAX3316E/MAX3317E
TRANSMITTER OUTPUT VOLTAGE
MAX3316E/MAX3317E
SUPPLY CURRENT vs. SUPPLY VOLTAGE
vs. SUPPLY VOLTAGE
10
6
T_OUT+
460kbps
230kbps
8
6
4
2
0
4
2
T1 TRANSMITTING AT 460kbps
T2 TRANSMITTING AT 20kbps
L
C = 1000pF
0
20kbps
-2
-4
-6
T1 TRANSMITTING AT SPECIFIED
DATA RATE
T2 TRANSMITTING AT 20kbps
T_OUT-
C = 1000pF
L
2.25 2.45 2.65 2.85 3.05 3.25 3.45 3.65
2.25 2.45 2.65 2.85 3.05 3.25 3.45 3.65
(V)
V
CC
(V)
V
CC
MAX3316E/MAX3317E
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3316E/MAX3317E
SLEW RATE vs. LOAD CAPACITANCE
5
4
10
8
FOR DATA RATES UP TO 460kps
T_OUT+
3
-SLEW
T1 TRANSMITTING AT 460kbps
T2 TRANSMITTING AT 20kbps
2
1
6
+SLEW
0
-1
-2
-3
-4
-5
4
2
T_OUT-
0
0
1000
2000
3000
0
1000
2000
3000
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
4
_______________________________________________________________________________________
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
Typical Operating Characteristics (continued)
(V
= +2.5V, C1–C4 = 0.1µF, 460ꢀbps data rate, all transmitters loaded with 3ꢀΩ, T = +25°C, unless otherwise noted.)
A
CC
MAX3316E/MAX3317E
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX3318E/MAX3319E
TRANSMITTER OUTPUT VOLTAGE
vs. SUPPLY VOLTAGE
MAX3318E/MAX3319E
SUPPLY CURRENT vs. SUPPLY VOLTAGE
15
12
9
35
6
4
T1 TRANSMITTING AT SPECIFIED DATA RATE
T2 TRANSMITTING AT 20kbps
460kbps
T_OUT+
30
25
20
15
10
5
230kbps
20kbps
460kbps
230kbps
2
T1 TRANSMITTING AT 460kbps
T2 TRANSMITTING AT 20kbps
C = 1000pF
L
0
6
-2
-4
-6
20kbps
T1 TRANSMITTING AT SPECIFIED
DATA RATE
3
T_OUT-
T2 TRANSMITTING AT 20kbps
C = 1000pF
L
0
0
2.25 2.45 2.65 2.85 3.05 3.25 3.45 3.65
0
1000
2000
3000
2.25 2.45 2.65 2.85 3.05 3.25 3.45 3.65
(V)
V
CC
(V)
LOAD CAPACITANCE (pF)
V
CC
MAX3318E/MAX3319E
OPERATING SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX3318E/MAX3319E
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3318E/MAX3319E
SLEW RATE vs. LOAD CAPACITANCE
5
35
30
25
20
15
10
5
10
8
T1 TRANSMITTING AT SPECIFIED
DATA RATE
T2 TRANSMITTING AT 20kbps
4
3
T_OUT+
-SLEW
+SLEW
2
460kbps
230kbps
T1 TRANSMITTING AT 460kbps
T2 TRANSMITTING AT 20kbps
1
6
0
4
-1
-2
-3
-4
-5
20kbps
2
T_OUT-
FOR DATA RATES UP TO 460kbs
0
0
0
1000
2000
3000
0
1000
2000
3000
0
1000
2000
3000
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
LOAD CAPACITANCE (pF)
_______________________________________________________________________________________
5
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
Typical Operating Characteristics (continued)
(V
= +2.5V, C1–C4 = 0.1µF, 460ꢀbps data rate, all transmitters loaded with 3ꢀΩ, T = +25°C, unless otherwise noted.)
A
CC
MAX3318E/MAX3319E
READY TURN-OFF TIME
vs. TEMPERATURE
MAX3318E/MAX3319E
READY TURN-ON TIME
vs. TEMPERATURE
TRANSMITTER SKEW vs.
LOAD CAPACITANCE (t - t )
PLH PHL
200
160
120
80
30
25
20
15
10
5
500
T1 TRANSMITTING AT 460kbps
T2 TRANSMITTING AT 20kbps
400
300
200
100
0
MAX3316E/MAX3317E
MAX3318E/MAX3319E
40
0
0
-40
-20
0
20
40
60
80
-40
-20
0
20
40
60
80
0
500 1000 1500 2000 2500 3000
LOAD CAPACITANCE (pF)
TEMPERATURE (°C)
TEMPERATURE (°C)
-in Description
PIN
NAME
FUNCTION
MAX3316E
MAX3317E MAX3318E MAX3319E
SSOP
TSSOP
Positive Terminal of Voltage-Doubler Charge-
Pump Capacitor
1
2
3
2
3
4
2
3
4
2
3
4
2
3
4
C1+
V+
+2 · V Generated bꢃ the Charge Pump
CC
Negative Terminal of Voltage-Doubler Charge-
Pump Capacitor
C1-
Positive Terminal of Inverting Charge-Pump
Capacitor
4
5
5
6
5
6
5
6
5
6
C2+
C2-
Negative Terminal of Inverting Charge-Pump
Capacitor
6
7, 14
8, 13
9, 12
10, 11
15
7
7
7
8, 17
9, 16
10, 15
12, 13
18
7
V-
-2 · V Generated bꢃ the Charge Pump
CC
8, 17
9, 16
12, 15
13, 14
18
8, 17
9, 16
10, 15
12, 13
18
13
8
T_OUT
R_IN
RS-232 Transmitter Outputs
RS-232 Receiver Inputs
CMOS Receiver Outputs
CMOS Transmitter Inputs
Ground
9
R_OUT
T_IN
11
14
15
—
—
GND
16
19
19
19
V
CC
+2.25V to +3.0V Single-Supplꢃ Voltage
Receiver Enable, Active Low
No Connection
—
1
—
EN
—
1, 10, 11, 20
11, 14
—
N.C.
6
_______________________________________________________________________________________
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
-in Description (continued)
PIN
NAME
FUNCTION
MAX3316E
SSOP TSSOP
MAX3317E MAX3318E MAX3319E
—
20
—
—
1
—
1
Shutdown Control, Active Low
SHDN
Readꢃ to Transmit Output, Active ꢁigh. READY is
enabled high when V- goes below -3.5V and the
device is readꢃ to transmit.
—
READY
Valid Signal Detector Output, Active Low. A logic
high indicates that a valid RS-232 level is present
on a receiver input.
—
—
—
—
11
14
10
12
INVALID
Force-On Input, Active ꢁigh. Drive high to override
AutoShutdown Plus, ꢀeeping transmitters and
receivers on (FORCEOFF must be high) (Table 1).
FORCEON
Force-Off Input, Active Low. Drive low to shut
down transmitters, receivers, and charge pump.
This overrides AutoShutdown Plus and FORCEON
(Table 1).
—
—
20
16
FORCEOFF
transmitters are turned off (high impedance) when
FORCEOFF is asserted low, or when the AutoShutdown
Plus circuitrꢃ senses that all receiver and transmitter
inputs are inactive for more than 30 seconds.
Detailed Description
Dual Chargeꢂ-ump koltage Converter
The MAX3316E–MAX3319Es’ internal power supplꢃ
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 discontinu-
ous 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 flꢃing capacitor (C1, C2) and a reservoir
capacitor (C3, C4) to generate the V+ and V- supplies.
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 V
.
CC
Rꢁꢂ232 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 alwaꢃs 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 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.
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. ꢂecause
INVALID indicates the receiver’s input condition, it
is independent of the states of FORCEON and
FORCEOFF.
Rꢁꢂ232 Compatible Transmitters
The MAX3316E–MAX3319Es’ transmitters are inverting
level translators that convert CMOS-logic levels to
RS-232 compatible voltage levels. Theꢃ guarantee a
460ꢀbps data rate with worst-case loads of 3ꢀΩ in parallel
with 1000pF, providing compatibilitꢃ with PC-to-PC
communication software (such as LapLinꢀ™).
MAX3317E ꢁhutdown Mode
Supplꢃ 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 , V- is
CC
pulled to ground, and the transmitter outputs are dis-
abled (high impedance). The time required to exit shut-
The MAX3317E’s transmitters are turned off (high
impedance) when SHDN is asserted low, putting the
device in shutdown mode. The MAX3318E/MAX3319Es’
LapLink is a trademark of Traveling Software.
_______________________________________________________________________________________
7
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
Table 1. Output Control Truth Table (MAX3318E/MAX3319E)
RECEIVER OR
OPERATION
STATUS
VALID RECEIVER TRANSMITTER
FORCEON
T_OUT
R_OUT
FORCEOFF
LEVEL
EDGE WITHIN
30s
Shutdown (Forced
Off)
X
0
X
X
X
X
ꢁigh-Z
Active
Active
ꢁigh-Z
Active
Active
ꢁigh-Z
Active
ꢁigh-Z
Active
Active
Active
Active
Normal Operation
(Forced On)
1
1
Normal Operation
(AutoShutdown Plus)
0
1
X
Yes
No
X
Shutdown
(AutoShutdown Plus)
0
1
X
Normal Operation
Normal Operation
Shutdown
1
Yes
X
Active
Active
Active
Active
Active
INVALID*
INVALID*
INVALID*
INVALID**
INVALID**
1
Yes
No
X
1
No
Yes
No
Normal Operation
(AutoShutdown)
INVALID**
INVALID**
Shutdown
(AutoShutdown)
X
X = Don’t care
*INVALID connected to FORCEON
sense a valid signal transition on anꢃ receiver or trans-
mitter input for 30 seconds. This maꢃ 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 sꢃstem turns on again when a
valid transition is applied to anꢃ RS-232 receiver or
transmitter input. As a result, the sꢃstem saves power
without changes to the existing ꢂIOS or operating sꢃstem.
**INVALID connected to FORCEON and FORCEOFF
Table 2. Shutdown and Enable Control
Truth Table (MAX3317E)
T_OUT
ꢁigh-Z
ꢁigh-Z
Active
Active
R_OUT
Active
ꢁigh-Z
Active
ꢁigh-Z
SHDN
EN
0
0
Figure 4a depicts valid and invalid RS-232 receiver volt-
age levels. INVALID indicates the receiver input’s condi-
tion 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 circuitrꢃ. When
neither control is asserted, the IC selects between these
states automaticallꢃ based on the last receiver or trans-
mitter edge received.
0
1
1
1
0
1
down is tꢃpicallꢃ 30µs, as shown in Figure 2. Connect
SHDN to V if the shutdown mode is not used; SHDN
CC
has no effect on R_OUT.
MAX3318E/MAX3319E
Autoꢁhutdown -lus Mode
When shut down, the device’s charge pumps turn off,
V+ is pulled to V , V- is pulled to ground, the transmitter
CC
Maxim’s AutoShutdown Plus feature on the MAX3318E/
MAX3319E allows the supplꢃ current to fall to 1µA.
These devices will enter the AutoShutdown Plus mode if
FORCEOFF is high, FORCEON is low, and theꢃ do not
outputs are high impedance, and READY is driven low.
The time required to exit shutdown is tꢃpicallꢃ 30µs
(Figure 2).
8
_______________________________________________________________________________________
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
+2.5V
0.1µF
C
BYPASS
V
CC
C1+
V+
V-
C3
0.1µF
C1
0.1µF
C1-
C2+
MAX3316E
MAX3317E
MAX3318E
MAX3319E
+5V
C4
0.1µF
C2
0.1µF
C2-
T_ OUT
R_ IN
T_ IN
RX
TX
RS-232
COMPLIANT
TRANSCEIVER
1000pF
R_ OUT
GND
Figure 1a. RS-232 Compatibility Circuit
V
OR SHDN
CC
(MAX3317E)
T1 IN
FORCEOFF
(MAX3318E/MAX3319E)
MAX3316E–MAX3319E
5V/div
5V/div
2V/div
T1
T2
T1 OUT
MAX3316E–MAX3319E
2V/div
RS-232 COMPLIANT
RECEIVER OUTPUT
5V/div
10µs/div
Figure 1b. MAX3316E–MAX3319E Transmitter Output
Compatibility with an RS-232 Receiver
Figure 2. Transmitter Outputs when Exiting Shutdown or
Powering Up
_______________________________________________________________________________________
9
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
ꢂꢃ connecting FORCEON to INVALID, the MAX3318E/
MAX3319E shut down when no valid receiver level is
detected and waꢀe up when a valid receiver level is
detected.
+0.3V
R_IN
A sꢃstem with AutoShutdown Plus maꢃ need time to
30µs
waꢀe up. Figure 5 shows a circuit that forces the trans-
mitters on for 100ms, allowing enough time for the other
sꢃstem to realize that the MAX3318E/MAX3319E is
awaꢀe. If the other sꢃstem outputs valid RS-232 signal
transitions within that time, the RS-232 ports on both
sꢃstems remain enabled.
TIMER
R
INVALID
-0.3V
INVALID ASSERTED IF ALL RECEIVER INPUTS ARE BETWEEN +0.3V AND -0.3V FOR
AT LEAST 30µs.
Connecting to the -C
(MAX3318E/MAX3319E)
Figure 3a. INVALID Functional Diagram, INVALID Low
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 ꢁot Sꢃnc™ 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
constantlꢃ the receiver or transmitter lines to determine
if the device is connected.
+2.7V
R_IN
30µs
TIMER
R
INVALID
-2.7V
INVALID DEASSERTED IF ANY RECEIVER INPUT HAS BEEN BETWEEN +2.7V AND -2.7V
FOR LESS THAN 30µs.
Figure 3b. INVALID Functional Diagram, INVALID High
1ꢀ5k EꢁD -rotection
All the pins on the MAX3316E–MAX3319E are protect-
ed against ESDs encountered during handling and
assemblꢃ. The driver outputs and receiver inputs have
extra protection against static electricitꢃ. Maxim’s engi-
neers have developed state-of-the-art structures to pro-
tect these pins against ESD of 15ꢀV 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 ꢀeep worꢀing without
latchup, whereas competing products can latch and
must be powered down to remove latchup.
INVALID HIGH
+2.7V
INDETERMINATE
+0.3V
0
INVALID LOW
INDETERMINATE
INVALID HIGH
-0.3V
ESD protection can be tested in various waꢃs; the trans-
mitter outputs and receiver inputs of the product familꢃ
are characterized for protection to the following limits:
-2.7V
•
•
15ꢀV using the ꢁuman ꢂodꢃ Model
8ꢀV using the IEC 1000-4-2 Contact Discharge
method
Figure 4a. Receiver Positive/Negative Thresholds for INVALID
•
15ꢀV using IEC 1000-4-2 Air-Gap method
Human Body Model
Figure 6a shows the ꢁuman ꢂodꢃ Model, and Figure 6b
shows the current waveform it generates when dis-
charged 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
1.5ꢀΩ resistor.
EꢁD Test Conditions
ESD performance depends on a varietꢃ of conditions.
Contact Maxim for a reliabilitꢃ report that documents
test setup, test methodologꢃ, and test results.
Hot Sync is a trademark of 3Com.
10 ______________________________________________________________________________________
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
RECEIVER
INPUTS
INVALID
REGION
}
TRANSMITTER
INPUTS
TRANSMITTER
OUTPUTS
V
INVALID
OUTPUT
CC
t
INVL
t
INVH
t
0
AUTOSHDN
t
AUTOSHDN
t
t
WU
WU
*V
CC
OUTPUT
0
V+
V
CC
0
V-
MAX3318E/MAX3319E
Figure 4b. AutoShutdown Plus, INVALID, and READY Timing Diagram
POWER-
R
C
1M
R
D
MASTER SHDN LINE
MANAGEMENT
1500Ω
0.1µF
1M
UNIT
DISCHARGE
RESISTANCE
CHARGE-CURRENT
LIMIT RESISTOR
FORCEOFF FORCEON
HIGH-
VOLTAGE
DC
DEVICE
UNDER
TEST
C
STORAGE
CAPACITOR
s
MAX3318E
MAX3319E
100pF
SOURCE
Figure 6a. Human Body ESD Test Model
Figure 5. AutoShutdown Plus Initial Turn-On to Wake Up a
Mouse or Another System
______________________________________________________________________________________ 11
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
IEC 1000ꢂ4ꢂ2
The IEC 1000-4-2 standard covers ESD testing and
performance of finished equipment; it does not specifi-
callꢃ refer to ICs. The MAX3316E–MAX3319E help ꢃou
design equipment that meets Level 4 (the highest level)
of IEC 1000-4-2 without the need for additional ESD-
protection components.
I 100%
P
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
I
r
90%
AMPERES
36.8%
The major difference between tests done using the
ꢁuman ꢂodꢃ Model and IEC 1000-4-2 is higher peaꢀ
current in IEC 1000-4-2 because series resistance is
lower in the IEC 1000-4-2 model. ꢁence, the ESD with-
stand voltage measured to IEC 1000-4-2 is generallꢃ
lower than that measured using the ꢁuman ꢂodꢃ
Model. Figure 7a shows the IEC 1000-4-2 model, and
Figure 7b shows the current waveform for the 8ꢀV, IEC
1000-4-2, Level 4, ESD Contact Discharge test.
10%
0
TIME
0
t
RL
t
DL
CURRENT WAVEFORM
Figure 6b. Human Body Current Waveform
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.
R
R
D
C
50M to 100M
330Ω
DISCHARGE
RESISTANCE
CHARGE-CURRENT
LIMIT RESISTOR
Machine Model
The Machine Model for ESD tests all pins using a
200pF storage capacitor and zero discharge resis-
tance. Its objective is to emulate the stress caused bꢃ
contact that occurs with handling and assemblꢃ during
manufacturing. All pins require this protection during
manufacturing, not just RS-232 inputs and outputs.
Therefore, after PC board assemblꢃ, the Machine Model
is less relevant to I/O ports.
HIGH-
VOLTAGE
DC
DEVICE
UNDER
TEST
C
s
STORAGE
CAPACITOR
150pF
SOURCE
Applications Information
Figure 7a. IEC 1000-4-2 ESD Test Model
Rꢁꢂ232 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 3ꢀΩ and 2500pF.
I
100%
90%
The receiver inputs are fullꢃ EIA-232 compliant.
The MAX3316E–MAX3319E will function properlꢃ with
most modern RS-232 interfaces. This allows RS-232
compatible communication in low-voltage sꢃstems without
the added expense of a voltage tripler or switched-
mode power supplꢃ.
10%
t
t = 0.7ns to 1ns
r
30ns
60ns
Figure 7b. IEC 1000-4-2 ESD Generator Current Waveform
12 ______________________________________________________________________________________
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
Capacitor ꢁelection
The capacitor tꢃpe used for C1–C4 is not critical for
V
CC
proper operation; polarized or nonpolarized capacitors
can be used. The charge pump requires 0.1µF capaci-
tors. Increasing the capacitor values (e.g., bꢃ a factor of
2) reduces ripple on the transmitter outputs and slightlꢃ
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
C
BYPASS
V
CC
C1+
V+
V-
C3*
C4
C1
MAX3316E
MAX3317E
MAX3318E
MAX3319E
C1-
C2+
C2, C3, C4, and C
to maintain proper ratios
BYPASS
(C1 to other capacitors).
C2
When using the minimum-required capacitor values,
maꢀe sure the capacitor value does not degrade exces-
sivelꢃ with temperature. If in doubt, use capacitors with
a higher nominal value. The capacitor’s equivalent
series resistance (ESR), which usuallꢃ rises at low tem-
peratures, influences the amount of ripple on V+ and V-.
C2-
T_ OUT
T_ IN
R_ IN
5k
R_ OUT
-owerꢂꢁupply Decoupling
In most circumstances, a 0.1µF bꢃpass capacitor is
adequate. In applications that are sensitive to power-
1000pF
FORCEON**
supplꢃ noise, decouple V
to ground with a capacitor
CC
V
CC
FORCEOFF**
of the same value as charge pump capacitor C1.
Connect bꢃpass capacitors as close to the IC as possible.
GND
Transmitter Outputs when
Exiting ꢁhutdown
*C3 CAN BE RETURNED TO V OR GND.
CC
**MAX3318E/MAX3319E
Figure 2 shows two transmitter outputs when exiting
shutdown mode. As theꢃ become active, the two trans-
mitter outputs are shown going to opposite RS-232 com-
patible levels (one transmitter input is high, the other is
low). Each transmitter is loaded with 3ꢀΩ in parallel with
2500pF. The transmitter outputs displaꢃ no ringing or
undesirable transients as theꢃ come out of shutdown.
Note that the transmitters are enabled onlꢃ when the
magnitude of V- exceeds approximatelꢃ -3V.
Figure 8. Loopback Test Circuit
2V/div
5V/div
T1 IN
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 loopbacꢀ test
circuit. Figure 9 shows a loopbacꢀ test result at
230ꢀbps. For Figure 9, all transmitters were driven
simultaneouslꢃ at 230ꢀbps into EIA/TIA-562 loads in
parallel with 1000pF.
T1 OUT
R1 OUT
2V/div
Chip Information
Figure 9. Loopback Test Result at 230kbps
TRANSISTOR COUNT: 1130
______________________________________________________________________________________ 13
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
-in Configurations (continued)
TOP VIEW
N.C.
C1+
V+
1
2
3
4
5
6
7
8
9
20 N.C.
19
EN
C1+
V+
1
2
3
4
5
6
7
8
9
20 SHDN
19
V
CC
V
CC
18 GND
18 GND
READY
C1+
V+
1
2
3
4
5
6
7
8
16 FORCEOFF
15
C1+
1
2
3
4
5
6
7
8
16 V
CC
C1-
17 T1OUT
16 R1IN
C1-
17 T1OUT
16 R1IN
V
CC
V+
C1-
15 GND
14 T1OUT
13 R1IN
12 R1OUT
11 T1IN
10 T2IN
MAX3316E
MAX3317E
C2+
C2-
C2+
C2-
14 GND
15 R1OUT
15 R1OUT
C1-
C2+
C2-
V-
MAX3319E
13 T1OUT
12 FORCEON
11 T1IN
C2+
MAX3316E
V-
14
V-
14
T1IN
N.C.
C2-
T2OUT
R2IN
13 T2IN
12 R2OUT
11 N.C.
T2OUT
R2IN
13 T1IN
12 T2IN
11 N.C.
V-
10 INVALID
T2OUT
R2IN
N.C. 10
R2OUT 10
R1IN
9
R1OUT
9
R2OUT
TSSOP
SSOP
SSOP/TSSOP
SSOP
14 ______________________________________________________________________________________
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
ꢁelector Guide
NO. OF DRIVERS/
RECEIVERS
GUARANTEED
DATA RATE (kbps)
AutoShutdown
Plus
PART
READY OUTPUT
SHUTDOWN
MAX3316E
MAX3317E
MAX3318E
MAX3319E
2/2
2/2
2/2
1/1
460
460
460
460
—
—
ꢁ
—
—
—
ꢁ
ꢁ
—
—
ꢁ
ꢁ
Typical Application Circuits
+2.5V
+2.5V
19
16
0.1µF
0.1µF
0.1µF
V
V
CC
CC
3
2
4
5
6
2
1
3
4
5
C1+
C1+
V+
V-
V+
C1
0.1µF
C3*
C3*
0.1µF
0.1µF
C1-
C2+
C1-
MAX3317E
7
6
MAX3316E
C2+
V-
C2
0.1µF
C4
0.1µF
C4
0.1µF
0.1µF
C2-
C2-
13
T1OUT
T2OUT
R1IN
T1IN
17
11
T1OUT
T2OUT
R1IN
T1IN
T2IN
14
7
RS-232
RS-232
COMPATIBLE
OUTPUTS
CMOS
INPUTS
CMOS
COMPATIBLE
INPUTS
OUTPUTS
8
T2IN
12
10
16
9
15 R1OUT
10 R2OUT
13
8
12 R1OUT
RS-232
RS-232
COMPATIBLE
INPUTS
CMOS
CMOS
OUTPUTS
5k
5k
COMPATIBLE
INPUTS
OUTPUTS
R2IN
9
R2OUT
R2IN
5k
5k
EN
1
20
SHDN
GND
18
GND
15
*C3 CAN BE RETURNED TO EITHER V OR GROUND.
CC
CIRCUIT SHOWN IS FOR THE 16-PIN SSOP.
Typical Application Circuits continue on next page.
______________________________________________________________________________________ 15
1ꢀ5k EꢁDꢂ-rotected, 2.ꢀk, 1µA, 4605bps,
Rꢁꢂ232 Compatible Transceivers
Typical Application Circuits (continued)
+2.5V
0.1µF
+2.5V
0.1µF
19
15
C
BYPASS
C
BYPASS
V
V
CC
CC
3
7
2
3
7
2
C1+
C1+
V+
V-
V+
V-
C1
0.1µF
C1
0.1µF
C3
C3
4
5
6
4
5
6
0.1µF
0.1µF
C1-
C2+
C1-
C2+
MAX3318E
MAX3319E
C4
0.1µF
C4
0.1µF
C2
0.1µF
C2
0.1µF
C2-
C2-
RS-232
COMPATIBLE
OUTPUT
13
T1IN
11
T1OUT 17
T1IN
T1OUT 13
CMOS
INPUT
CMOS
INPUTS
RS-232 COMPATIBLE
OUTPUTS
RS-232
COMPATIBLE
INPUT
8
T2IN
T2OUT
12
9
R1OUT
R1IN
5k
8
CMOS
OUTPUT
16
15 R1OUT
10 R2OUT
R1IN
CMOS
OUTPUTS
RS-232 COMPATIBLE
INPUTS
TO POWER-
MANAGEMENT
UNIT
5k
READY
INVALID 10
1
AutoShutdown
Plus
R2IN
9
FORCEOFF
FORCEON
16
12
V
CC
5k
GND
14
TO POWER-
MANAGEMENT
UNIT
AutoShutdown
Plus
READY
INVALID 11
1
FORCEOFF
FORCEON
20
14
V
CC
GND
18
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 -roducts, 120 ꢁan Gabriel Drive, ꢁunnyvale, CA 94086 408ꢂ737ꢂ7600
© 2000 Maxim Integrated Products
Printed USA
is a registered trademarꢀ of Maxim Integrated Products.
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