LT1330_15 Datasheet, PDF (1/10 Pages) Linear Technology – 5V RS232 Transceiver with 3V Logic Interface and One Receiver Active in Shutdown

FEATURES
n _{3V Logic Interface}
n _{ESD Protection over ±10kV}
n _{Uses Small Capacitors: 0.1μF, 0.2μF, 1.0μF}
n _{One Low Power Receiver Remains Active While in}
Shutdown
n _{Pin Compatible with LT1137A and LT1237}
n _{120kBaud Operation for RL = 3k, CL = 2500pF}
n _{250kBaud Operation for RL = 3k, CL = 1000pF}
n _{CMOS Comparable Low Power: 30mW}
n _{Easy PC Layout—Flowthrough Architecture}
n _{Rugged Bipolar Design}
n _{Outputs Assume a High Impedance State When Off}
or Powered Down
n _{Absolutely No Latchup}
n _{60μA Supply Current in Shutdown}
n _{Available in SO and SSOP Packages}
APPLICATIONS
n _{Notebook Computers}
n _{Palmtop Computers}
LT1330
5V RS232 Transceiver with
3V Logic Interface and One
Receiver Active in Shutdown
DESCRIPTION
The LT^®1330 is a three driver, five receiver RS232 trans-
ceiver with low supply current. Designed to interface
with new 3V logic, the LT1330 operates with both a 5V
power supply and a 3V logic power supply. The chip may
be shut down to micropower operation with one receiver
remaining active to monitor RS232 inputs such as ring
detect from a modem.
The LT1330 is fully compliant with all EIA RS232 spec-
ifications. Additionally, the RS232 line input and output pins
are resilient to multiple ±10kV ESD strikes. This eliminates
the need for costly TransZorbs^® on line pins for the RS232
part.
The LT1330 operates to 120kbaud even driving high
capacitive loads. During shutdown, driver and receiver
outputs are at a high impedance state allowing devices to
be paralleled.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
TransZorb is a registered trademark of General Instrments, GSI.
TYPICAL APPLICATION
V⁺ 1
1.0μF
2 s 0.1μF
5V V_CC ²
3
4
DRIVER 1 OUT ⁵
RX1 IN ⁶
DRIVER 2 OUT ⁷
TO
LINE
RX2 IN ⁸
RX3 IN ⁹
RX4 IN ¹⁰
DRIVER 3 OUT ¹¹
RX5 IN (LOW-Q) ¹²
ON/OFF ¹³
3V V_L ¹⁴
LT1330
28 V^–
27
26
2 s 0.1μF
25 _{DRIVER 1 IN}
0.1μF
RECEIVER
OUTPUT
V_L = 3V
C_L = 50pF
24
RX1 OUT
23
DRIVER 2 IN
22 _{RX2 OUT}
21 _{RX3 OUT}
TO LOGIC
DRIVER
OUTPUT
R_L = 3k
C_L = 2500pF
20
RX4 OUT
19
DRIVER 3 IN
18 RX5 OUT (LOW-Q)
RING DETECT IN
INPUT
17 GND
16 ^DRIVER
DISABLE
μCONTROLLER OR
μPROCESSOR
15
SHUTDOWN
CONTROL OUT
1330 TA01
Output Waveforms
1330 TA02
1330fb
1