Datasheet

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General Description

The MAX3386E 3V-powered EIA/TIA-232 and V.28/V.24

is a communications interface with low power require-

ments, high data-rate capabilities, and enhanced elec-

trostatic discharge (ESD) protection. The MAX3386E

has two receivers and three transmitters. All RS-232

inputs and outputs are protected to ±25kV 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.

A proprietary low-dropout transmitter output stage

enables true RS-232 performance from a +3.0V to +5.5V

supply with a dual charge pump. The charge pump

requires only four small 0.1µF capacitors for operation

from a +3.3V supply. The MAX3386E is capable of

running at data rates up to 250kbps while maintaining

RS-232 compliant output levels.

The MAX3386E has a unique V

pin that allows interop-

eration in mixed-logic voltage systems. Both input and

output logic levels are pin programmable through the

pin. The MAX3386E is available in a space-saving

TSSOP package.

Applications

Subnotebook/Palmtop Computers

PDAs and PDA Cradles

Cell Phone Data Cables

Battery-Powered Equipment

Hand-Held Equipment

Peripherals

Features

♦ V

Pin for Compatibility with Mixed-Voltage

Systems

♦ Enhanced ESD Protection on Rx Inputs and Tx

Outputs

±15kV—Human Body Model

±25kV—IEC 1000-4-2, Air-Gap Discharge

±8kV—IEC 1000-4-2, Contact Discharge

♦ Low 300µA Supply Current

♦ Guaranteed 250kbps Data Rate

♦ 1µA Low-Power Shutdown

♦ Meets EIA/TIA-232 Specifications Down to 3.0V

MAX3386E

3.0V, ±25kV ESD-Protected RS-232

Transceiver for PDAs and Cell Phones

________________________________________________________________ Maxim Integrated Products 1

SHDN

GND

T1OUTC2+

C1-

V+

C1+

TOP VIEW

T2OUT

T3OUT

R1IN

R2INT2IN

T1IN

V-

C2-

R1OUTR2OUT

T3IN

TSSOP

MAX3386E

R2OUT10

R1OUT

R2IN

GND

RS-232

OUTPUTS

TTL/CMOS

INPUTS

T2IN

T1IN

C2-

C2+

C1-

C1+

R1IN

T2OUT

T1OUT

V-

V+

0.1µF

BYPASS

+3.3V

T3IN

T3OUT

RS-232

INPUTS

TTL/CMOS

OUTPUTS

5kΩ

0.1µF

SHDN

Typical Operating Circuit

19-1529; Rev 3; 4/01

PART

MAX3386ECUP

MAX3386EEUP -40°C to +85°C

0°C to +70°C

TEMP. RANGE PIN-PACKAGE

20 TSSOP

Pin Configuration

Ordering Information

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Summary of content (11 pages)

PAGE 1
9-1529; Rev 3; 4/01 3.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones The MAX3386E 3V-powered EIA/TIA-232 and V.28/V.24 is a communications interface with low power requirements, high data-rate capabilities, and enhanced electrostatic discharge (ESD) protection. The MAX3386E has two receivers and three transmitters.
PAGE 2
MAX3386E 3.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones ABSOLUTE MAXIMUM RATINGS VCC to GND ..............................................................-0.3V to +6V VL to GND...................................................-0.3V to (VCC + 0.3V) V+ to GND ................................................................-0.3V to +7V V- to GND .................................................................+0.3V to -7V V+ + V-(Note 1) ..............................................
PAGE 3
.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones (VCC = VL = +3.0V to +5.5V; C1–C4 = 0.1µF, tested at +3.3V ±10%; C1 = 0.047µF, C2–C4 = 0.33µF, tested at +5.0V ±10%; TA = TMIN to TMAX; unless otherwise noted. Typical values are at VCC = VL = +3.3V, TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS RECEIVER INPUTS TRANSMITTER OUTPUTS Output Voltage Swing All transmitter outputs loaded with 3kΩ to ground ±5 ±5.
PAGE 4
Typical Operating Characteristics (VCC = VL = +3.3V, TA = +25°C, unless otherwise noted.) TRANSMITTER OUTPUT VOLTAGE vs. LOAD CAPACITANCE 2.5 MAX3386E toc 02 DATA RATE = 250kbps LOAD = 3kΩ IN PARALLEL WITH CL 14 12 SLEW RATE (V/µs) OUTPUT VOLTAGE (V) 5.0 SLEW RATE vs. LOAD CAPACITANCE 16 MAX3386E toc 01 7.5 0 -2.5 SLEW RATE 10 SLEW RATE + 8 6 4 -5.0 2 -7.5 0 1000 2000 3000 4000 0 5000 TRANSMITTER OUTPUT VOLTAGE vs.
PAGE 5
3.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones PIN NAME FUNCTION 1 C1+ 2 V+ +5.5V Supply Generated by the Charge Pump 3 C1- Negative Terminal of the Voltage-Doubler Charge-Pump Capacitor 4 C2+ Positive Terminal of the Inverting Charge-Pump Capacitor 5 C2- Negative Terminal of the Inverting Charge-Pump Capacitor Positive Terminal of the Voltage-Doubler Charge-Pump Capacitor 6 V- 7 T1IN -5.
PAGE 6
MAX3386E 3.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones Detailed Description Dual Charge-Pump Voltage Converter The MAX3386E’s internal power supply consists of a regulated dual charge pump that provides output voltages of +5.5V (doubling charge pump) and -5.5V (inverting charge pump), regardless of the input voltage (VCC) over a +3.0V to +5.5V range. The charge pumps operate in a discontinuous mode: if the output voltages are less than 5.
PAGE 7
3.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones RC 1MΩ CHARGE-CURRENT LIMIT RESISTOR HIGHVOLTAGE DC SOURCE Cs 100pF MAX3386E VL Logic Supply Input Unlike other RS-232 interface devices where the receiver outputs swing between 0 and VCC, the MAX3386E features a separate logic supply input (VL) that sets VOH for the receiver outputs and sets thresholds for the transmitted and shutdown inputs.
PAGE 8
MAX3386E 3.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones RC 50MΩ to 100MΩ CHARGE-CURRENT LIMIT RESISTOR HIGHVOLTAGE DC SOURCE Cs 150pF Machine Model RD 330Ω DISCHARGE RESISTANCE DEVICE UNDER TEST STORAGE CAPACITOR 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.
PAGE 9
3.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones Interconnection with 3V and 5V Logic VCC 0.1µF VCC C1+ C1 C1- V+ C3 MAX3386E C2+ VC4 C2 C2- The MAX3386E can directly interface with various 5V logic families, including ACT and HCT CMOS. The logic voltage power-supply pin VL sets the output voltage level of the receivers and the input thresholds of the transmitters.
PAGE 10
MAX3386E 3.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones T1IN 5V/div T1OUT 5V/div 5V/div R1OUT VCC = +3.3V 2µs/div Figure 7.
PAGE 11
3.0V, ±25kV ESD-Protected RS-232 Transceiver for PDAs and Cell Phones TSSOP.EPS MAX3386E Package Information 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.