File name 1992.PDF
19-1437; Rev 0; 3/99
±15kV ESD-Protected, 3.0V to 5.5V, Low-Power, up to 250kbps, True RS-232 Transceiver
The MAX3385E is a 3V-powered EIA/TIA-232 and V.28/V.24 communications interface with low power requirements, high data-rate capabilities, and enhanced electrostatic discharge (ESD) protection. All transmitter outputs and receiver inputs are protected to ±15kV using IEC 1000-4-2 Air-Gap Discharge, ±8kV using IEC 1000-4-2 Contact Discharge, and ±15kV using the Human Body Model. The transceiver has a proprietary low-dropout transmitter output stage, delivering 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. Each device is guaranteed to run at data rates of 250kbps while maintaining RS-232 output levels. The MAX3385E has two receivers and two drivers. It features a 1µA shutdown mode that reduces power consumption and extends battery life in portable systems. Its receivers can remain active in shutdown mode, allowing external devices such as modems to be monitored using only 1µA supply current. The MAX3385E is available in a space-saving SSOP package in either the commercial (0°C to +70°C) or extended-industrial (-40°C to +85°C) temperature range.
o 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 o Latchup Free o 300µA Supply Current o 1µA Low-Power Shutdown with Receivers Active o 250kbps Guaranteed Data Rate o 250µs Time to Exit Shutdown with 3k Load on V+ o 6V/µs Guaranteed Slew Rate o Meets EIA/TIA-232 Specifications Down to 3.0V
PART MAX3385ECAP MAX3385EEAP TEMP. RANGE 0°C to +70°C -40°C to +85°C PIN-PACKAGE 20 SSOP 20 SSOP
Typical Operating Circuit
+3.3V CBYPASS C1 0.1µF 2 C1+ 4 5 C119 VCC V+ 3 C3* 0.1µF 7 C4 0.1µF
Hand-Held Equipment Peripherals Printers Battery-Powered Equipment
N.C. 1 C1+ 2 V+ 3 C1- 4 C2+ 5 C2- 6 V- 7 T2OUT 8 R2IN 9 N.C. 10 20 SHDN 19 VCC 18 GND 17 T1OUT
14 T1IN TTL/CMOS INPUTS 13 T2IN
T1OUT 17 RS-232 OUTPUTS T2OUT 8
15 R1OUT TTL/CMOS OUTPUTS 12 R2OUT
R1IN 16 5k R2IN 9 5k GND 18 SHDN 20 RS-232 INPUTS
16 R1IN 15 R1OUT 14 T1IN 13 T2IN 12 R2OUT 11 N.C.
* C3 CAN BE RETURNED TO EITHER VCC OR GROUND.
NOTE: SEE TABLE 2 FOR CAPACITOR SELECTION
Covered by U.S. Patent numbers 4,636,930; 4,679,134; 4,777,577; 4,797,899; 4,809,152; 4,897,774; 4,999,761; and other patents pending.
________________________________________________________________ Maxim Integrated Products
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800. For small orders, phone 1-800-835-8769.
±15kV ESD-Protected, 3.0V to 5.5V, Low-Power, up to 250kbps, True RS-232 Transceiver MAX3385E