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FEATURES
Compatible with DS1229
5V operation
20-pin DIP or SOIC package
20-pin TSSOP package for height restricted
applications
Operate from single +5V power
Meets all EIA-232E and V.28 specifications
Uses small capacitors: 0.1 µF
Optional industrial temperature range
available (-40°C to +85°C)
ORDERING INFORMATION
DS229 20-pin DIP
DS229N 20-pin DIP (Industrial)
DS229S 20-pin SOIC
DS229SN 20-pin SOIC (Industrial)
DS229E 20-pin TSSOP
DS229EN 20-pin TSSOP (Industrial)
PIN ASSIGNMENT
PIN DESCRIPTION
VCC - +5-Volt Supply
GND - Ground
V+ - Positive Supply Output
V- - Negative Supply Output
T1IN, T2IN, T3IN - RS-232 Driver Inputs
T1OUT, T2OUT, T3OUT - RS-232 Driver Outputs
R1IN, R2IN, R3IN - Receiver Inputs
R1OUT, R2OUT, R3OUT - Receiver Outputs
C1+, C1- - Capacitor 1 Connections
C2+, C2- - Capacitor 2 Connections
DESCRIPTION
The DS229 is a triple RS-232 driver/receiver pair that generates RS-232 voltage levels from a single +5-
volt power supply. Additional ±12-volt supplies are not needed since the DS229 uses on-board charge
pumps to convert the +5-volt supply to ±10 volts. The DS229 is fully compliant with EIA RS-232E and
V.28/V.24 standards. The DS229 contains three drivers and three receivers. Driver slew rates and data
rates are guaranteed up to 116 kbits/sec. The DS229 operates with only 0.1 µF charge pump capacitors.
OPERATION
The diagram in Figure 1 shows the main elements of the DS229. The following paragraphs describe the
function of each pin.
DS229
Triple RS-232 Transmitte r/Receive
r
www.dalsemi.com
20-Pin DIP, SOIC AND TSSOP
19
C1-
C2-
T2
OU
T
R2
IN
T3
OUT
R3
IN
V
CC
R1
IN
R1
OUT
T1
IN
T2IN
R2
OUT
T3IN
R3
OUT
1
2
3
4
5
6
7
8
9
10
20
18
17
16
15
14
13
12
11
V+
C2+
V-
C1+
GND
T1
OUT
DS229
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FUNCTIONAL DIAGRAM OF DS229 Figure 1
NOTE: C5 is a recommended decoupling capacitor which is the same value as C1, C2, C3, and C4.
PIN DESCRIPTIONS
VCC, GND: DC power is provided to the device on these pins. VCC is the +5-volt input.
V+: Positive suppl y output (RS-232). V+ requires an ex ternal storage charge capacitor of at least 0.1 µF.
A larger capacitor (up to 10 µF) can be used to reduce supply ripple.
DS229
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V-: Negative supply output (RS-232). V- requires an external storage capacitor of at least 0.1 µF. A
larger capacitor (up to 10 µF) can be used to reduce supply ripple.
T1IN, T2IN, T3IN: Standard TTL/CMOS inputs for the RS-232 drivers. The inputs of unused drivers can
be left unconnected since each input has a 400 kΩ pullup resistor.
T1OUT, T2OUT, T3OUT: Driver outputs at RS-232 levels. Driver output swing meets RS-232 levels for
loads up to 3 kΩ. These driver outputs provide current necessary to meet RS-232 levels for loads up to
2500 pF.
R1IN, R2IN, R3IN: Receiver inputs. These inputs accept RS-232 level signals (±25 volts) into a protected
5 kΩ terminating resistor. Each receiver provides 0.5V hysteresis (typical) for noise immunity.
R1OUT, R2OUT, R3OUT: Receiver outputs at TTL/CMOS levels.
C1+, C1-, C2+, C2-: Charge pump capacitor inputs. These pins require two external capacitors (0.1 µF
minimum, 10 µF maximum and should be the same size as C3 and C4). Capacitor 1 is connect ed betwe en
C1+ and C1-. Capacitor 2 is connected between C2+ and C2-. Capacitor C1 can be omitted if +12 volts is
connected directly to V+. Likewise, C2 can be omitted if -12V is connected directly to V-.
DUAL CHARGE PUMP CONVERTERS
The DS229 has a two stage on-board char ge pump circuit that is used to generate ±10 volts from a single
+5-volt supply. In the first stage, capacitor C1 doubles the +5V suppl y to +10 volts which is then stored
on capacitor C3. The second stage uses capacitor C2 to invert the +10V potential to -10V. This charge is
then stored on capacitor C4. The ±10-volt supplies allow the DS229 to provide the necessary output
levels for RS-232 communication. The DS229 will operate with charge pump capacitors as low as 0.1
µF. Larger capacitors (up to 10 µF) can be used to reduce supply ripple.
RS-232 DRIVERS
The three RS-232 drivers are powered b y the internal ±10-volt supplies generated b y the on-board char ge
pump. The driver inputs are both TTL and CMOS compatible. Each input has an internal 400 kΩ=pullup
resistor so that unused transmitter inputs can be left unconnected. Th e open circuit output voltage swing
is from (V+ - 0.6) to V- volts. Worst case conditions for E IA-232E/V.28 of ±5 volts driving a 3 kΩ=load
and 2500 pF are met at maximum operating temperature and VCC equal to 4.5 volts. Typical voltage
swings of ±8 volts occur when loaded with a nominal 5 kΩ=RS-232 receiver. As required by EIA-232E
and V.28 specifications, the slew rate at the output is limited to less than 30 volts/µs. Typical slew rates
are 20 volts/µs unloaded and 12 volts/µs with 3 kΩ=and 2500 pF load. These slew rat es allow for bit rates
of over 116 kbits/s. Driver outputs maintain high impedance when power is off.
RS-232 RECEIVERS
The three receivers conform fully to the RS-232E specifications. The input impedance is typically 5
kΩ=and can withstand up to ±30 volts with or without VCC applied. The input switching thresholds are
within the ±3-volt limit of RS-232E specification with an input threshold low of 0.8 volts and an input
threshold high of 2.4 volts. The receivers have 0.5 volts of h ysteresis (typical) to improve noise rej ection.
The TTL/CMOS compatible outputs of the receivers will be low whenever the RS-232 input is greater
than 2.4 volts. The receiver output will be high when the input is floating or driven between +0.8 volts
and -25 volts.
DS229
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ABSOLUTE MAXIMUM RA TINGS*
Absolute Maximum Ratings
VCC -0.3V to +7.0V
V+ (VCC-0.3V) to +14V
V- +0.3V to -14V
Input Voltages
TIN -0.3V to (VCC+0.3V)
RIN ±30V
Output Voltages
TOUT (V+ + 0.3V) to (V- - 0.3V)
ROUT -0.3V to (VCC+ 0.3V)
Short Circuit Duration, TOUT Continuous
* This is a stress rating only and functional operation of the device at these or any other conditions
above those indicated in the operation sections of this specification is not implied. Exposure to
absolute maximum rating conditions for extended periods of time may affect reliability.
RECOMMENDED DC OPERA T ING CONDITIONS (0°C to 70°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Operating Supply Voltage VCC 4.5 5.5 V 1
DC ELECTRICAL CHARACTERISTICS (0°C to 70°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Power Supply Current (No Load) ICC1 615mA
Power Supply Current (3 kΩ Lo a d A ll
Outputs) ICC2 22.5 mA
RS-232 Transmitters
Output Voltage Swing VORS ±5±8V2
Input Logic Threshold Low VTTL 0.8 1.4 V
Input Logic Threshold High VTTH 1.4 2.0 V
Data Rate fD200 116 kbits/s
Logic Pullup/Input Current IPU 540
µA
Transmitter Output Resistance ROUT 300 10M Ω3
Output Short-Circuit Current ITSC ±15 ±30 ±100 mA 4
DS229
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DC ELECTRICAL CHARACTERI STI CS (continued) (0°C to 70°C)
RS-232 Receivers
RS-232 Input Voltage Operating Range VIR ±25 ±30 V
RS-232 Input Threshold Low VRTL 0.8 1.3 V
RS-232 Input Threshold High VRTH 1.8 2.4 V
RS-232 Input Hysteresis VHY 0.2 0.5 1 V
RS-232 Input Resistance RIN 357
kΩ
TTL/CMOS Output Voltage Low VROL 0.2 0.4 V 5
TTL/CMOS Output Voltage High VROH 3.5 VCC-0.2 V 6
TTL/CMOS Output Short Circuit
Current (VOUT=GND) IRSC -2 -10 mA
TTL/CMOS Output Short Circuit
Current (VOUT=VCC)IRSC 10 30 mA
AC ELECTRICAL CHA RACTERISTICS (0°C to 70°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Transition Slew Rate tSR 61230
V/µs7
Transmitter Propagation
Delay TTL to RS-232 tPHLT
tPLHT
1.3
1.5 3.5
3.5 µs
µs
Receiver Propagation
Delay RS-232 to TTL tPHL
R
tPLHR
0.5
0.6 1
1µs
µs
Transmitter + to - Propagation
Delay Difference tPHLT
-tPLHT
300 ns
Receiver + to - Propagation
Delay Difference tPHL
R
-tPLHR
100 ns
NOTES:
1. All voltages are referenced to ground.
2. All transmitter outputs loaded with 3 kΩ=to ground
3. VCC = V+ = V- = 0V; VOUT = ±2V.
4. VOUT = 0V.
5. IOUT = 3.2 mA.
6. IOUT = -1.0 mA.
7. CL = 50 pF - 2500 pF; RL = 3 kΩ=- 7 kΩ; VCC = 5V; TA = 25°C.
DS229
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TRANSMITTER PROP AGATION DELAY TIMING Figure 2
RECEIVER PROPAGATION DELAY TIMING Figure 3
DS229
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20-PIN DIP (300-MIL)
PKG 20-PIN
DIM MIN MAX
A IN.
MM 0.970
24.63 1.040
26.42
B IN.
MM 0.240
6.09 0.270
6.86
C IN.
MM 0.120
3.05 0.140
3.56
D IN.
MM 0.295
7.49 0.325
8.26
E IN.
MM 0.015
0.38 0.040
1.02
F IN.
MM 0.120
3.04 0.140
3.56
G IN.
MM 0.090
2.23 0.110
2.79
H IN.
MM 0.310
7.87 0.390
9.91
J IN.
MM 0.008
0.20 0.012
0.30
K IN.
MM 0.015
0.38 0.021
0.53
DS229
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20-PIN SOIC (300-MIL)
PKG 20-PIN
DIM MIN MAX
A IN.
MM 0.094
2.39 0.105
2.67
A1 IN.
MM 0.004
0.102 0.012
0.30
A2 IN.
MM 0.089
2.26 0.095
2.41
b IN.
MM 0.013
0.33 0.020
0.51
C IN.
MM 0.009
0.229 0.013
0.33
D IN.
MM 0.498
12.65 0.511
12.99
e IN.
MM 0.050 BSC
1.27 BSC
E1 IN.
MM 0.290
7.37 0.300
7.62
H IN.
MM 0.398
10.11 0.416
10.57
L IN.
MM 0.016
0.40 0.040
1.02
Θ
ΘΘ
Θ0°8°
DS229
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20-PIN TSSOP
DIM MIN MAX
A MM -1.10
A1 MM 0.05 -
A2 MM 0.75 1.05
C MM 0.09 0.18
L MM 0.50 0.70
e1 MM 0.65 BSC
B MM 0.18 0.30
D MM 6.40 6.90
E MM 4.40 NOM
G MM 0.25 REF
H MM 6.25 6.55
phi 0°8°
