SP202E_04 Datasheet, PDF (4/15 Pages) Sipex Corporation – High-Performance RS-232 Line Drivers/Receivers

FEATURES…
The SP202E/232E/233E/310E/312E devices
are a family of line driver and receiver pairs that
meet the specifications of RS-232 and V.28
serial protocols with enhanced ESD perfor-
mance. The ESD tolerance has been improved
on these devices to over ±15KV for both Human
Body Model and IEC1000-4-2 Air Discharge
Method. These devices are pin-to-pin compat-
ible with Sipex's 232A/233A/310A/312A
devices as well as popular industry standards.
As with the initial versions, the SP202E/232E/
233E/310E/312E devices feature10V/µs slew
rate, 120Kbps data rate under load, 0.1µF
charge pump capacitors, overall ruggedness
for commercial applications, and increased drive
current for longer and more flexible cable
configurations. This family also features Sipex's
BiCMOS design allowing low power operation
without sacrificing performance.
The SP202E/232E/233E/310E/312E devices
have internal charge pump voltage converters
which allow them to operate from a single +5V
supply. The charge pumps will operate with
polarized or non-polarized capacitors ranging
from 0.1 to 10 µF and will generate the ±6V
needed to generate the RS-232 output levels.
Both meet all EIA RS-232 and ITU V.28
specifications.
The SP310E provides identical features as the
SP232E with a single control line which
simultaneously shuts down the internal DC/DC
converter and puts all transmitter and receiver
outputs into a high impedance state. The SP312E
is identical to the SP310E with separate tri-state
and shutdown control lines.
THEORY OF OPERATION
The SP232E, SP233E, SP310E and SP312E
devices are made up of three basic circuit blocks –
1) a driver/transmitter, 2) a receiver and 3) a charge
pump. Each block is described below.
Driver/Transmitter
The drivers are inverting transmitters, which ac-
cept TTL or CMOS inputs and output the RS-232
signals with an inverted sense relative to the input
logic levels. Typically the RS-232output voltage
swing is ±6V. Even under worst case loading
conditions of 3kOhms and 2500pF, the output is
guaranteed to be ±5V, which is consistent with the
RS-232 standard specifications. The transmitter
outputs are protected against infinite short-circuits
to ground without degradation in reliability.
+5V INPUT
10
µF
6.3V
+
1
0.1µ F ⁺
6.3V
3
4
0.1µ F ⁺
16V
5
16
C ₁+
V _CC
C 1-
Charge Pump
C ₂+
C 2-
T₁ IN
11
T₂ IN
10
400k Ω
T₁
400k Ω
T₂
0.1µ F 6.3V
V+ ²
*
V- ⁶
+ 0.1µ F
16V
14
T ₁OUT
7
T ₂OUT
R₁OUT
12
R₁
13
R ₁IN
5k Ω
R₂OUT
9
R₂
8
R ₂IN
SP202E
SP232E
5k Ω
GND 15
*The negative terminal of the V+ storage capacitor can be tied
to either VCC or GND. Connecting the capacitor to VCC (+5V)
is recommended.
Figure 1. Typical Circuit using the SP202E or SP232E.
Date: 7/19/04
SP202E Series High Performance RS232 Transceivers
4
© Copyright 2004 Sipex Corporation