现货库存、技术资料、百科信息、热点资讯，精彩尽在鼎好!
General Description
The MAX3311/MAX3313 are low-power, +5V EIA/TIA232-compatible transceivers. Both devices have one
transmitter and one receiver. The transceivers have a
proprietary low-dropout transmitter output stage
enabling RS-232-compatible operation from a +5V supply with a single inverting charge pump. These devices
require only three 0.1µF capacitors and will run at data
rates up to 460kbps while maintaining RS-232-compatible output levels.
The MAX3311 features a 1µA shutdown mode. In shutdown the device turns off the charge pump, pulls V- to
ground, and the transmitter output is disabled. The
MAX3313 features an INVALID output that asserts high
when an active RS-232 cable signal is connected, signaling to the host that a peripheral is connected to the
communication port.
________________________Applications
Digital Cameras
PDAs
GPS
POS
Telecommunications
Handy Terminals
Set-Top Boxes
Features
♦ 1µA Low-Power Shutdown (MAX3311)
♦ INVALID Output (MAX3313)
♦ Receiver Active in Shutdown (MAX3311)
♦ Single Transceiver (1Tx/1Rx) in 10-Pin µMAX
♦ RS-232-Compatible Operation
MAX3311/MAX3313
460kbps, 1µA Supply Current,
RS-232-Compatible Transceivers in µMAX
________________________________________________________________ Maxim Integrated Products 1
Pin Configurations
19-1901; Rev 0; 2/01
Ordering Information
For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
Pin Configurations continued at end of data sheet.
Typical Operating Circuit
C1
0.1µF
C2
0.1µF
C
BYPASS
0.1µF
98
1
10
7
6
3
2
4
5
C1+ V-
TOUT
C1-
TIN
RINROUT
V
CC
GND
5kΩ
SHDN (MAX3311)
INVALID (MAX3313)
+5V
MAX3311
MAX3313
CAPACITORS MAY BE POLARIZED OR NONPOLARIZED.
PART TEMP. RANGE PIN-PACKAGE
MAX3311CUB 0°C to +70°C 10 µMAX
MAX3311EUB -40°C to +85°C 10 µMAX
MAX3313CUB 0°C to +70°C 10 µMAX
MAX3313EUB -40°C to +85°C 10 µMAX
TOP VIEW
1
V
CC
2
C1-
3
SHDN
4
5
10
GND
9
MAX3311
µMAX
8
7
6
C1+
V-
TOUTTIN
RINROUT
MAX3311/MAX3313
460kbps, 1µA Supply Current,
RS-232-Compatible Transceivers in µMAX
2_________________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC= +5V, C1 and C2 = 0.1µF, TA= T
MIN
to T
MAX
. Typical values are at TA= +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 .................................................................+0.3V to -7V
V
CC
+ |V-|.............................................................................+13V
Input Voltages
TIN, SHDN to GND .................................................-0.3V to +6V
RIN to GND ........................................................................±25V
Output Voltages
TOUT to GND..................................................................±13.2V
ROUT, INVALID to GND .......................…-0.3V to (V
CC
+ 0.3V)
Short-Circuit Duration
TOUT to GND ...........................................................Continuous
Continuous Power Dissipation
10-Pin µMAX (derate 5.6mW/°C above +70°C) .............444mW
Operating Temperature Ranges
MAX331_CUB .......................................................0°C to +70°C
MAX331_EUB ....................................................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
PARAMETER SYMBOL CONDITIONS MIN TYP MAX U N IT S
DC CHARACTERISTICS
Supply Operation Range V
CC
Supply Current SHDN = V
4.5 5 5.5 V
CC
Shutdown Supply Current SHDN = GND (MAX3311 only) 1 10 µA
LOGIC INPUTS (TIN, SHDN)
Input Logic Threshold Low V
Input Logic Threshold High V
0.8 V
IL
2.4 V
IH
Transmitter Input Hysteresis 0.5 V
Input Leakage Current ±0.01 ±1 µA
RECEIVER OUTPUT
Output Voltage Low V
Output Voltage High V
OL
OH
I
= 1.6mA 0.4 V
OUT
I
= -1.0mA
OUT
INVALID OUTPUT (MAX3313 ONLY)
Receiver Input Threshold to
INVALID Output High
Receiver Input Threshold to
INVALID Output Low
Figure 5 -0.3 0.3 V
INVALID Output Low V
INVALID Output High V
Receiver Positive or Negative
Threshold to INVALID High
Receiver Positive or Negative
Threshold to INVALID Low
Figure 5 0.1 µs
Figure 5 30 µs
OL
OH
Figure 5, positive threshold 2.7
Figure 5, negative threshold -2.7
I
= 1.6mA 0.4 V
OUT
I
= -1.0mA VCC - 0.6 V
OUT
, no load 100 250 µA
V
-
V
CC
0.6
CC
0.1
-
V
V
MAX3311/MAX3313
460kbps, 1µA Supply Current,
RS-232-Compatible Transceivers in µMAX
_______________________________________________________________________________________ 3
Note 1:
Not tested—guaranteed by design.
TIMING CHARACTERISTICS
(VCC= +5V, C1 and C2 = 0.1µF, TA= T
MIN
to T
MAX
. Typical values are at TA= +25°C.)
ELECTRICAL CHARACTERISTICS (continued)
(VCC= +5V, C1 and C2 = 0.1µF, TA= T
MIN
to T
MAX
. Typical values are at TA= +25°C.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX U N IT S
RECEIVER INPUT
Input Threshold Low V
Input Threshold High V
0.8 V
IL
2.4 V
IH
Input Hysteresis 0.5 V
Input Resistance 5 kΩ
TRANSMITTER OUTPUT
Transmitter output loaded with 3kΩ to
Output Voltage Swing
Output Resistance (Note 1) V
ground
= 0, transmitter output = ±2V 300 Ω
CC
±3.7 V
Output Short-Circuit Current ±60 mA
Output Leakage Current V
= ±12V, transmitter disabled ±25 µA
OUT
PARAMETER SYMBOL CONDITIONS MIN TYP MAX U N IT S
Maximum Data Rate R
Receiver Propagation Delay
t
PLH
t
PHL
= 3kΩ, C
L
,
Recei ver i np ut to r ecei ver outp ut
C
= 150p F
L
= 1000p F 460 kbps
L
0.15 µs
Transmitter Skew 100 ns
Receiver Skew 50 ns
Transition Region Slew Rate
R
= 3kΩ to 7kΩ, CL = 150pF to 1000p F,
L
m easur ed from +3V to - 3V or fr om - 3V to + 3V
11
V/µs
MAX3311/MAX3313
460kbps, 1µA Supply Current,
RS-232-Compatible Transceivers in µMAX
4 _______________________________________________________________________________________
Typical Operating Characteristics
(VCC= +5V, 0.1µF capacitors, transmitter loaded with 3kΩ and CL, TA= +25°C, unless otherwise noted.)
0
4
2
8
6
12
10
14
0 1000 1500500 2000 2500 3000
SLEW RATE
vs. LOAD CAPACITANCE
MAX3311/13 toc01
LOAD CAPACITANCE (pF)
SLEW RATE (V/µs)
+SLEW
250 kbps DATA RATE
-SLEW
-5
-4
-3
-2
-1
0
1
2
3
4
5
6
0 500 10001500200025003000
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CAPACITANCE
MAX3311/13 toc02
LOAD CAPACITANCE (pF)
TRANSMITTER OUTPUT VOLTAGE (V)
460kbps/250kbps/120kbps
460kbps/250kbps/120kbps
0
4
2
8
6
12
10
14
0 1000 1500500 2000 2500 3000
SUPPLY CURRENT
vs. LOAD CAPACITANCE
MAX3311/13 toc03
LOAD CAPACITANCE (pF)
SUPPLY CURRENT (mA)
20kbps
120kbps
250kbps
460kbps
Pin Description
PIN
MAX3311 MAX3313
11V
2 2 C1- Negative Terminal of the Voltage Inverter Charge-Pump Capacitor
3 — SHDN Shutdown Active-Low (0 = off, 1 = on)
— 3 INVALID
4 4 TIN TTL/CMOS Transmitter Input
5 5 ROUT TTL/CMOS Receiver Output
6 6 RIN RS-232 Receiver Input
7 7 TOUT RS-232-Compatible Transmitter Output
8 8 V- -4.3V generated by the charge pump. Connect a 0.1µF capacitor to ground.
9 9 C1+ Positive Terminal of the Voltage Inverter Charge-Pump Capacitor
10 10 GND Ground
NAME FUNCTION
CC
+5V External Power Supply. Decouple with a 0.1µF capacitor to ground.
Valid Signal Detector Output, Active-Low. A logic high indicates that a valid
RS-232 level is present on the receiver input.
MAX3311/MAX3313
460kbps, 1µA Supply Current,
RS-232-Compatible Transceivers in µMAX
_______________________________________________________________________________________ 5
Detailed Description
Single Charge-Pump Voltage Converter
The MAX3311/MAX3313 internal power supply has a
single inverting charge pump that provides a negative
voltage from a single +5V supply. The charge pump
operates in a discontinuous mode and requires a flying
capacitor (C1) and a reservoir capacitor (C2) to generate the V- supply.
RS-232-Compatible Driver
The transmitter is an inverting level translator that converts CMOS-logic levels to EIA/TIA-232-compatible levels. It guarantees data rates up to 460kbps with
worst-case loads of 3kΩ in parallel with 1000pF. When
SHDN is driven low, the transmitter is disabled and put
into three state. The transmitter input does not have an
internal pullup resistor.
RS-232 Receiver
The MAX3311/MAX3313 receiver converts RS-232 signals to CMOS-logic output levels. The MAX3311 receiver will remain active during shutdown mode. The
MAX3313 INVALID indicates when an RS-232 signal is
present at the receiver input, and therefore when the
port is in use.
The MAX3313 INVALID output is pulled low when no
valid RS-232 signal level is detected on the receiver
input.
MAX3311 Shutdown Mode
In shutdown mode, the charge pump is turned off, V- is
pulled to ground, and the transmitter output is disabled
(Table 1). This reduces supply current typically to 1µA.
The time required to exit shutdown is typically less than
100µs.
Applications Information
Capacitor Selection
The capacitor type used for C1 and C2 is not critical for
proper operation; either polarized or nonpolarized
capacitors are acceptable. If polarized capacitors are
used, connect polarity as shown in the Typical
Operating Circuit. The charge pump requires 0.1µF
capacitors. Increasing the capacitor values (e.g., by a
factor of 2) reduces power consumption. C2 can be
increased without changing C1’s value. However, do
not increase C1’s value without also increasing the
value of C2 and C
BYPASS
to maintain the proper ratios
(C1 to the other capacitors).
When using the minimum 0.1µF capacitors, make sure
the capacitance does not degrade excessively with
temperature. If in doubt, use capacitors with a larger
nominal value. The capacitor’s equivalent series resistance (ESR) usually rises at low temperatures and influences the amount of ripple on V-.
To reduce the output impedance at V-, use larger
capacitors (up to 10µF).
Bypass VCCto ground with at least 0.1µF. In applications sensitive to power-supply noise generated by the
charge pump, decouple VCCto ground with a capacitor the same size as (or larger than) charge-pump
capacitors C1 and C2.
Transmitter Output when Exiting
Shutdown
Figure 1 shows the transmitter output when exiting
shutdown mode. The transmitter is loaded with 3kΩ in
parallel with 1000pF. The transmitter output displays no
ringing or undesirable transients as the MAX3311
comes out of shutdown. Note that the transmitter is
enabled only when the magnitude of V- exceeds
approximately -3V.
Table 1. MAX3311 Shutdown Logic Truth
Table
Figure 1. Transmitter Output when Exiting Shutdown or
Powering Up
SHDN
TRANSMITTER
OUTPUT
L High Z Active Inactive
H Active Active Active
RECEIVER
OUTPUT
CHARGE
PUMP
5V/div
0
1.5V/div
0
10µs/div
TIN = GND
TIN = V
CC
SHDN
TOUT
MAX3311/MAX3313
High Data Rates
The MAX3311/MAX3313 maintain RS-232-compatible
transmitter output voltage (±3.7V minimum) even at
high data rates. Figure 2 shows a transmitter loopback
test circuit. Figure 3 shows the loopback test result at
120kbps, and Figure 4 shows the same test at
250kbps.
460kbps, 1µA Supply Current,
RS-232-Compatible Transceivers in µMAX
6 _______________________________________________________________________
Figure 2. Loopback Test Circuit
Figure 4. Loopback Test Results at 250kbps
Figure 3. Loopback Test Results at 120kbps
Figure 5. Receiver Positive/Negative Thresholds for
INVALID
+5V
0.1µF
V
C1+
C1
C1-
CC
MAX3311
MAX3313
V-
C2
TIN
TIN
ROUT
GND
TOUT
RIN
5kΩ
1000pF
TIN
TOUT
ROUT
5µs/div
INVALID HIGH
+2.7V
INDETERMINATE
+0.3V
0
-0.3V
RECEIVER INPUT LEVELS
-2.7V
INVALID LOW
INDETERMINATE
INVALID HIGH
TOUT
ROUT
2µs/div
460kbps, 1µA Supply Current,
RS-232-Compatible Transceivers in µMAX
MAX3311/MAX3313
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 7
© 2001 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.
Package Information
Chip Information
TRANSISTOR COUNT: 278
Pin Configurations (continued)
V
C1-
INVALID
1
CC
2
MAX3313
3
4
5
µMAX
10
GND
9
C1+
8
V-
7
TOUTTIN
RINROUT
6
10LUMAX.EPS
Loading...