AD ADM208EARU Emi/emc compliant, -15 kv esd protected, rs-232 line drivers/receiver Datasheet

a
EMI/EMC Compliant, ⴞ15 kV ESD Protected,
RS-232 Line Drivers/Receivers
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
FEATURES
Complies with 89/336/EEC EMC Directive
ESD Protection to IEC1000-4-2 (801.2)
ⴞ8 kV: Contact Discharge
ⴞ15 kV: Air-Gap Discharge
ⴞ15 kV: Human Body Model
Fast Transient Burst (EFT) Immunity (IEC1000-4-4)
Low EMI Emissions (EN55022)
Eliminates Costly TranZorbs*
460 kbits/s Data Rate Guaranteed
Single +5 V Power Supply
Shutdown Mode 1 ␮W
Plug-In Upgrade for MAX2xxE
Space Saving TSSOP Package Available
FUNCTIONAL BLOCK DIAGRAM
+5V INPUT
0.1mF
10V
0.1mF
10V
CMOS
INPUTS*
APPLICATIONS
Laptop Computers
Notebook Computers
Printers
Peripherals
Modems
12 C1+ +5V TO +10V VCC 11
VOLTAGE
14 C1– DOUBLER
V+ 13
15 C2+ +10V TO –10V V– 17
T1IN
7
T2IN
6
T3IN
20
T4IN
21
R1OUT
8
R2OUT
5
R3OUT
26
R4OUT
22
R5OUT
19
EN (ADM211E)
EN (ADM213E)
24
CMOS
OUTPUTS
VOLTAGE
INVERTER
16 C2–
T1
T2
T3
T4
0.1mF
6.3V
0.1mF
0.1mF
10V
2
T1OUT
3
T2OUT
1
T3OUT
28
T4OUT
EIA/TIA-232
OUTPUTS
9
R1IN
4
R2IN
27
R3IN
23
R4IN
R5
18
R5IN
ADM211E
25
SHDN (ADM211E)
SHDN (ADM213E)
R1
R2
R3
R4
GND ADM213E
EIA/TIA-232
INPUTS**
10
GENERAL DESCRIPTION
The ADM2xxE is a family of robust RS-232 and V.28 interface
devices that operates from a single +5 V power supply. These
products are suitable for operation in harsh electrical environments and are compliant with the EU directive on EMC (89/336/
EEC). The level of emissions and immunity are both in compliance. EM immunity includes ESD protection in excess of ±15 kV
on all I-O lines (1000-4-2), Fast Transient Burst protection (10004-4) and Radiated Immunity (1000-4-3). EM emissions include
radiated and conducted emissions as required by Information
Technology Equipment EN55022, CISPR22.
All devices fully conform to the EIA-232E and CCITT V.28
specifications and operate at data rates up to 230 kbps.
NOTES:
* INTERNAL 400kV PULL-UP RESISTOR ON EACH CMOS INPUT
** INTERNAL 5kV PULL-DOWN RESISTOR ON EACH RS-232 INPUT
charge pump, all transmitters, and three of the five receivers are
disabled. The remaining two receivers remain active thereby
allowing monitoring of peripheral devices. This feature allows
the device to be shut down until a peripheral device begins communication. The active receivers can alert the processor which
can then take the ADM213E out of the shutdown mode.
Operating from a single +5 V supply, four external 0.1 µF
capacitors are required.
Shutdown and Enable control pins are provided on some of the
products. Please refer to Table I.
The ADM207E and ADM208E are available in 24-lead DIP,
SO, SSOP and TSSOP packages. The ADM211E and ADM213E
are available in 28-lead SO, SSOP and TSSOP packages.
The shutdown function on the ADM211E disables the charge
pump and all transmitters and receivers. On the ADM213E the
All products are backward compatible with earlier ADM2xx
products facilitating easy upgrading of older designs.
*TranZorb is a registered trademark of General Semiconductor Industries, Inc.
Table I. Selection Table
Model
Supply Voltage
Drivers
Receivers
ESD Protection
Shutdown
Enable
Packages
ADM206E
ADM207E
ADM208E
ADM211E
ADM213E
+5 V
+5 V
+5 V
+5 V
+5 V
4
5
4
4
4
3
3
4
5
5
± 15 kV
± 15 kV
± 15 kV
± 15 kV
± 15 kV
Yes
No
No
Yes
Yes (SD)*
Yes
No
No
Yes
Yes (EN)
R-24
N, R, RS, RU-24
N, R, RS, RU-24
R, RS, RU-28
R, RS, RU-28
*Two receivers active.
REV. B
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 1998
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E–SPECIFICATIONS
(VCC = +5.0 V ⴞ 10%, C1–C4 = 0.1 ␮F. All specifications TMIN to TMAX unless otherwise noted.)
Parameter
Min
Typ
Max
Units
Test Conditions/Comments
Operating Voltage Range
VCC Power Supply Current
+4.5
+5.0
3.5
+5.5
6
Volts
mA
No Load
Shutdown Supply Current
0.2
5
µA
Input Pull-Up Current
Input Logic Threshold Low, VINL
Input Logic Threshold High, VINH
Input Logic Threshold High, VINH
CMOS Output Voltage Low, VOL
CMOS Output Voltage High, VOH
CMOS Output Leakage Current
10
25
0.8
µA
V
V
V
V
V
µA
EIA-232 Input Voltage Range
EIA-232 Input Threshold Low
EIA-232 Input Threshold High
EIA-232 Input Hysteresis
EIA-232 Input Resistance
Output Voltage Swing
2.0
2.4
0.4
3.5
0.05
–30
0.4
±5
+30
0.2
3
± 5.0
1.3
2.0
0.7
5
± 9.0
2.4
1.0
7
Transmitter Output Resistance
RS-232 Output Short Circuit Current
300
± 10
± 20
± 60
Maximum Data Rate
230
460
Receiver Propagation Delay
TPHL, TPLH
Receiver Output Enable Time, tER
Receiver Output Disable Time, tDR
Transmitter Propagation Delay
TPHL, TPLH
Transition Region Slew Rate
ESD Protection (I-O Pins)
ESD Protection (All Other Pins)
EFT Protection (I-O Pins)
EMI Immunity
0.4
120
120
3
1
10
2
30
± 15
± 15
±8
± 2.5
±2
10
V
V
V
V
kΩ
Volts
Ω
mA
TIN = GND
TIN, EN, EN, SHDN, SHDN,
TIN
EN, EN, SHDN, SHDN
IOUT = 1.6 mA
IOUT = –40 µA
EN = VCC, EN = GND, 0 V ≤ ROUT ≤ VCC
All Transmitter Outputs
Loaded with 3 kΩ to Ground
VCC = 0 V, VOUT = ± 2 V
kbps
kbps
RL = 3 kΩ to 7 kΩ, CL = 50 pF to 2500 pF
CL = 1000 pF (ADM206E)
µs
ns
ns
CL = 150 pF
µs
V/µs
RL = 3 kΩ, CL = 2500 pF
RL = 3 kΩ, CL = 50 pF to 2500 pF
Measured from +3 V to –3 V or
–3 V to +3 V
kV
kV
kV
kV
kV
V/m
Human Body Model
IEC1000-4-2 Air Discharge
IEC1000-4-2 Contact Discharge
Human Body Model, MIL-STD-883B
IEC1000-4-4
IEC1000-4-3
Specifications subject to change without notice.
–2–
REV. B
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
ABSOLUTE MAXIMUM RATINGS*
(TA = +25°C unless otherwise noted)
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +6 V
V+ . . . . . . . . . . . . . . . . . . . . . . . . . . . . (VCC –0.3 V) to +14 V
V– . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +0.3 V to –14 V
Input Voltages
TIN . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to (V+, +0.3 V)
RIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 30 V
Output Voltages
TOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 15 V
ROUT . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to (VCC +0.3 V)
Short Circuit Duration
TOUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Continuous
Power Dissipation
N-24 DIP (Derate 13.5 mW/°C Above +70°C) . . 1000 mW
R-24 SOIC (Derate 12 mW/°C Above +70°C) . . . 900 mW
RS-24 SSOP (Derate 12 mW/°C Above +70°C) . . . . 850 mW
RU-24 TSSOP (Derate 12 mW/°C Above +70°C) . . 900 mW
R-28 SOIC (Derate 12 mW/°C Above +70°C) . . . . . 900 mW
RS-28 SSOP (Derate 10 mW/°C Above +70°C) . . . . 900 mW
RU-28 TSSOP (Derate 12 mW/°C Above +70°C) . . 900 mW
Operating Temperature Range
Industrial (A Version) . . . . . . . . . . . . . . . . –40°C to +85°C
Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C
Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . . +300°C
ESD Rating (MIL-STD-883B) (I-O Pins) . . . . . . . . . . ± 15 kV
ESD Rating (MIL-STD-883B) (Except I-O) . . . . . . . ± 2.5 kV
ESD Rating (IEC1000-4-2 Air) (I-O Pins) . . . . . . . . . ± 15 kV
ESD Rating (IEC1000-4-2 Contact) (I-O Pins) . . . . . . ± 8 kV
EFT Rating (IEC1000-4-4) (I-O Pins) . . . . . . . . . . . . . ± 2 kV
*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.
Table II. ADM211E Truth Table
ORDERING GUIDE
SHDN
EN
Status
TOUT1-4
ROUT1-5
Model
Temperature Range
Package Option
0
0
Enabled
Enabled
0
1
Enabled
Disabled
1
X
Normal
Operation
Normal
Operation
Shutdown
Disabled
Disabled
ADM206EAR
ADM207EAN
ADM207EAR
ADM207EARS
ADM207EARU
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
R-24
N-24
R-24
RS-24
RU-24
ADM208EAN
ADM208EAR
ADM208EARS
ADM208EARU
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
N-24
R-24
RS-24
RU-24
ADM211EAR
ADM211EARS
ADM211EARU
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
R-28
RS-28
RU-28
ADM213EAR
ADM213EARS
ADM213EARU
–40°C to +85°C
–40°C to +85°C
–40°C to +85°C
R-28
RS-28
RU-28
X = Don’t Care.
Table III. ADM213E Truth Table
SHDN
EN
Status
TOUT1-4
ROUT1-3
ROUT4-5
0
0
1
0
1
0
Disabled
Disabled
Enabled
Disabled
Disabled
Disabled
Disabled
Enabled
Disabled
1
1
Shutdown
Shutdown
Normal
Operation
Normal
Operation
Enabled
Enabled
Enabled
REV. B
–3–
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
T3OUT 1
24 T4OUT
T3OUT 1
24 T4OUT
T1OUT 2
23 R2IN
T1OUT 2
23 R2IN
T2OUT 3
22 R2OUT
T2OUT 3
22 R2OUT
R1IN 4
21 SD
R1IN 4
R1OUT 5
20 EN
R1OUT 5
T2IN 6
ADM206E
TOP VIEW 19 T4IN
T1IN 7 (Not to Scale) 18 T3IN
T2IN 6
GND 8
GND 8
21 T5IN
ADM207E
20 T5OUT
TOP VIEW 19 T4IN
T1IN 7 (Not to Scale) 18 T3IN
17 R3OUT
17 R3OUT
VCC 9
16 R3IN
VCC 9
C1+ 10
15 V–
C1+ 10
16 R3IN
15 V–
V+ 11
14 C2–
V+ 11
14 C2–
C1– 12
13 C2+
C1– 12
13 C2+
Figure 1. ADM206E DIP/SOIC/SSOP Pin Configuration
Figure 3. ADM207E Pin Configuration
+5V INPUT
+5V INPUT
0.1mF
6.3V
10 C1+
12 C1–
0.1mF
16V
TTL/CMOS
INPUTS*
TTL/CMOS
OUTPUTS
13 C2+
14 C2–
+5V TO +10V
VOLTAGE
DOUBLER
+10V TO –10V
VOLTAGE
INVERTER
VCC
0.1mF
10V
9
V+ 11
0.1mF
6.3V
0.1mF
16V
T1IN
7
T1
2
T1OUT
T2IN
6
T2
3
T2OUT
CMOS
INPUTS*
RS-232
OUTPUTS
T3IN
18
T3
1
T3OUT
T4IN
19
T4
24
T4OUT
R1OUT
5
R1
4
R1IN
R2OUT
22
R2
23
R2IN
R3OUT
17
R3
16
R3IN
EN
20
21
SD
GND
ADM206E
12 C1–
+5V TO +10V
VOLTAGE
DOUBLER
VCC
9
V+ 11
0.1mF
6.3V
0.1mF
0.1mF
0.1mF
10V
V– 15
10 C1+
RS-232
INPUTS**
CMOS
OUTPUTS
13 C2+
14 C2–
+10V TO –10V
VOLTAGE
INVERTER
0.1mF
10V
T1IN
7
T1
2
T1OUT
T2IN
6
T2
3
T2OUT
T3IN
18
T3
1
T3OUT
T4IN
19
T4
24
T4OUT
T5IN
21
T5
20
T5OUT
R1OUT
5
R1
4
R1IN
R2OUT
22
R2
23
R2IN
R3OUT
17
R3
16
R3IN
GND
8
V– 15
EIA/TIA-232
OUTPUTS
EIA/TIA-232
INPUTS**
ADM207E
8
*INTERNAL 400kV PULL-UP RESISTOR ON EACH TTL/CMOS INPUT
**INTERNAL 5kV PULL-DOWN RESISTOR ON EACH RS-232 INPUT
*INTERNAL 400kV PULL-UP RESISTOR ON EACH CMOS INPUT
**INTERNAL 5kV PULL-DOWN RESISTOR ON EACH RS-232 INPUT
Figure 2. ADM206E Typical Operating Circuit
Figure 4. ADM207E Typical Operating Circuit
–4–
REV. B
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
T2OUT 1
24 T3OUT
T1OUT 2
23 R3IN
R2IN 3
22 R3OUT
T1IN 5
ADM208E
20 T4OUT
TOP VIEW 19 T3IN
R1IN 7 (Not to Scale) 18 T2IN
16 R4IN
C1+ 10
15 V–
C1– 12
25 SHDN
22 R4OUT
T1IN 7
14 C2–
V+ 11
26 R3OUT
R2IN 4
21 T4IN
R1OUT 8
17 R4OUT
VCC 9
27 R3IN
T2OUT 3
ADM211E 24 EN
TOP VIEW
T2IN 6 (Not to Scale) 23 R4IN
R1OUT 6
GND 8
28 T4OUT
T1OUT 2
R2OUT 5
21 T4IN
R2OUT 4
T3OUT 1
13 C2+
R1IN 9
20 T3IN
GND 10
19 R5OUT
VCC 11
18 R5IN
C1+ 12
17 V–
V+ 13
16 C2–
C1– 14
15 C2+
Figure 7. ADM211E Pin Configuration
Figure 5. ADM208E Pin Configuration
+5V INPUT
0.1mF
10V
+5V INPUT
0.1mF
10V
0.1mF
10V
10 C1+
12 C1–
13 C2+
14 C2–
+5V TO +10V
VOLTAGE
DOUBLER
+10V TO –10V
VOLTAGE
INVERTER
VCC
9
V+ 11
V– 15
0.1mF
6.3V
0.1mF
0.1mF
10V
0.1mF
10V
T1IN
5
T1
2
T1OUT
T2IN
18
T2
1
T2OUT
CMOS
INPUTS*
CMOS
INPUTS*
EIA/TIA-232
OUTPUTS
T3IN
19
T3
24
T3OUT
T4IN
21
T4
20
T4OUT
R1OUT
6
R1
7
R1IN
R2OUT
4
R2
3
R2IN
R3OUT
22
R3
23
R3IN
R4OUT
17
R3
16
R4IN
CMOS
OUTPUTS
TTL/CMOS
OUTPUTS
EIA/TIA-232
INPUTS**
GND
ADM208E
8
14 C1–
15 C2+
16 C2–
+5V TO +10V
VOLTAGE
DOUBLER
+10V TO –10V
VOLTAGE
INVERTER
VCC 11
V+ 13
V– 17
0.1mF
6.3V
0.1mF
0.1mF
10V
T1IN
7
T1
2
T1OUT
T2IN
6
T2
3
T2OUT
EIA/TIA-232
OUTPUTS
T3IN
20
T3
1
T3OUT
T4IN
21
T4
28
T4OUT
R1OUT
8
R1
9
R1IN
R2OUT
5
R2
4
R2IN
R3OUT
26
R3
27
R3IN
R4OUT
22
R4
23
R4IN
R5OUT
19
R5
18
R5IN
EN
24
25
SHDN
GND
ADM211E
EIA/TIA-232
INPUTS**
10
*INTERNAL 400kV PULL-UP RESISTOR ON EACH CMOS INPUT
**INTERNAL 5kV PULL-DOWN RESISTOR ON EACH RS-232 INPUT
*INTERNAL 400kV PULL-UP RESISTOR ON EACH CMOS INPUT
**INTERNAL 5kV PULL-DOWN RESISTOR ON EACH RS-232 INPUT
Figure 6. ADM208E Typical Operating Circuit
REV. B
12 C1+
Figure 8. ADM211E Typical Operating Circuit
–5–
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
+5V INPUT
0.1mF
16V
0.1mF
16V
T3OUT 1
28 T4OUT
T1OUT 2
27 R3IN
T2OUT 3
26 R3OUT
25 SHDN
R2IN 4
R2OUT 5
TOP VIEW
T2IN 6 (Not to Scale) 23 R4IN*
22 R4OUT*
R1OUT 8
21 T4IN
R1IN 9
20 T3IN
GND 10
19 R5OUT*
VCC 11
18 R5IN*
C1+ 12
17 V–
V+ 13
16 C2–
C1– 14
15 C2+
14 C1–
15 C2+
16 C2–
+5V TO +10V VCC 11
VOLTAGE
DOUBLER
V+ 13
+10V TO –10V
VOLTAGE
INVERTER
V– 17
0.1mF
6.3V
TTL/CMOS
OUTPUTS
*ACTIVE IN SHUTDOWN
0.1mF
0.1mF
16V
T1IN
7
T1
2
T1OUT
T2IN
6
T2
3
T2OUT
T3IN
20
T3
1
T3OUT
T4IN
21
T4
28
T4OUT
RS-232
OUTPUTS
TTL/CMOS
INPUTS*
ADM213E 24 EN
T1IN 7
12 C1+
R1OUT
8
R1
9
R1IN
R2OUT
5
R2
4
R2IN
R3OUT
26
R3
27
R3IN
R4OUT***
22
R4
23
R4IN***
R5OUT***
19
R5
18
R5IN***
EN
24
25
SHDN
GND
ADM213E
RS-232
INPUTS**
10
*INTERNAL 400kV PULL-UP RESISTOR ON EACH CMOS INPUT
**INTERNAL 5kV PULL-DOWN RESISTOR ON EACH RS-232 INPUT
***ACTIVE IN SHUTDOWN
Figure 10. ADM213E Typical Operating Circuit
Figure 9. ADM213E Pin Configuration
PIN FUNCTION DESCRIPTIONS
Mnemonic
Function
VCC
V+
V–
GND
C1+, C1–
Power Supply Input: +5 V ± 10%.
Internally Generated Positive Supply (+9 V nominal).
Internally Generated Negative Supply (–9 V nominal).
Ground Pin. Must Be Connected to 0 V.
External Capacitor 1 is connected between these pins. 0.1 µF capacitor is recommended but larger capacitors up
to 47 µF may be used.
External Capacitor 2 is connected between these pins. 0.1 µF capacitor is recommended but larger capacitors up
to 47 µF may be used.
Transmitter (Driver) Inputs. These inputs accept TTL/CMOS levels. An internal 400 kΩ pull-up resistor to VCC
is connected on each input.
Transmitter (Driver) Outputs. These are RS-232 signal levels (Typically ± 9 V).
Receiver Inputs. These inputs accept RS-232 signal levels. An internal 5 kΩ pull-down resistor to GND is
connected on each input.
Receiver Outputs. These are CMOS output logic levels.
Receiver Enable (Active High on ADM213E, Active Low on ADM211E); This input is used to enable/disable the
receiver outputs. With EN = Low ADM211E (EN = High ADM213E), the receiver outputs are enabled. With EN
= High (EN = Low ADM213E), the receiver outputs are placed in a high impedance state.
Shutdown Control (Active Low on ADM213E, Active High on ADM211E); Refer to Table II. In shutdown the
charge pump is disabled, the transmitter outputs are turned off and all receiver outputs (ADM211E), receivers R1,
R2, R3 (ADM213E) are placed in a high impedance state. Receivers R4 and R5 on the ADM213E continue to
operate normally during shutdown. Power consumption in shutdown for all parts reduces to 5 µW.
C2+, C2–
TIN
TOUT
RIN
ROUT
EN/EN
SHDN/SHDN
–6–
REV. B
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
Typical Performance Curves
80
80
70
70
60
LIMIT
60
50
dBmV
dBmV
50
40
30
30
20
20
10
10
0
0.3
0.6
3
6
1
LOG FREQUENCY – MHz
18
LIMIT
40
0
30
START 30.0 MHz
Figure 14. EMC Radiated Emissions
Figure 11. EMC Conducted Emissions
10
8
8
TOUT (+VE)
TOUT (+VE)
6
4
2
VCC = +5V
RL = 3kV
6
4
2
0
0
–2
–2
TOUT (–VE)
TOUT VOLTAGE – V
STOP 200.0 MHz
–4
TOUT (–VE)
–6
–4
–6
–8
–8
50
1000
2000
–10
3.0
2500
3.5
4.0
18
VCC = +5V
16
16
14
14
12
12
IOUT – mA
IOUT – mA
5.5
18
VCC = 5V
10
8
10
8
6
6
4
4
2
2
4.0
5.0
6.0
TOUT – V
7.0
8.0
0
–9.8
9.7
–8.0
–7.0
–6.0
TOUT – V
–5.0
–4.0
–3.0
Figure 16. Transmitter Output Voltage Low vs.
Load Current
Figure 13. Transmitter Output Voltage High vs.
Load Current
REV. B
5.0
Figure 15. Transmitter Output Voltage vs. VCC
Figure 12. Transmitter Output Voltage High/Low vs.
Load Capacitance @ 230 kbps
0
3.0
4.5
VCC – V
CL – pF
–7–
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
250
SHDN
1
200
IMPEDANCE – V
V–
+10V
V+
2
150
100
V+
3
50
V–
–10V
0
20ms/DIV
Figure 17. Charge Pump V+, V– Exiting Shutdown
3
3.5
4
4.5
VCC – V
5
5.5
6
Figure 18. Charge Pump Impedance vs. VCC
10
8
V+
VCC = +5V
CHARGE PUMP VOLTAGE
6
4
2
0
–2
–4
V–
–6
–8
–10
0
5
10
15
20
25
I LOAD – mA
30
35
40
Figure 19. Charge Pump V+, V– vs. Current
–8–
REV. B
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
GENERAL DESCRIPTION
All RS-232 inputs and outputs contain protection against
electrostatic discharges up to ± 15 kV and electrical fast transients up to ± 2 kV. This ensures compliance to IE1000-4-2 and
IEC1000-4-4 requirements.
The devices are ideally suited for operation in electrically harsh
environments or where RS-232 cables are frequently being
plugged/unplugged. They are also immune to high RF field
strengths without special shielding precautions.
Emissions are also controlled to within very strict limits.
CMOS technology is used to keep the power dissipation to an
absolute minimum allowing maximum battery life in portable
applications. The ADMxxE is a modification, enhancement and
improvement to the AD230–AD241 family and derivatives
thereof. It is essentially plug-in compatible and does not have
materially different applications.
CIRCUIT DESCRIPTION
The internal circuitry consists of four main sections. These are:
1. A charge pump voltage converter.
2. 5 V logic to EIA-232 transmitters.
3. EIA-232 to 5 V logic receivers.
4. Transient protection circuit on all I-O lines.
Charge Pump DC-DC Voltage Converter
The charge pump voltage converter consists of an 200 kHz
oscillator and a switching matrix. The converter generates a
± 10 V supply from the input +5 V level. This is done in two
stages using a switched capacitor technique as illustrated below.
First, the 5 V input supply is doubled to 10 V using capacitor
C1 as the charge storage element. The 10 V level is then inverted to generate –10 V using C2 as the storage element.
Capacitors C3 and C4 are used to reduce the output ripple. If
desired, larger capacitors (up to 47 µF) can be used for capacitors C1–C4. This facilitates direct substitution with older generation charge pump RS-232 transceivers.
The V+ and V– supplies may also be used to power external
circuitry if the current requirements are small. Please refer to
Figure 19 in the Typical Performance section.
S3
S1
VCC
V+ = 2VCC
S4
GND
INTERNAL
OSCILLATOR
Figure 20. Charge Pump Voltage Doubler
REV. B
V+
FROM
VOLTAGE
DOUBLER
GND
C4
C2
S2
S4
GND
V– = –(V+)
INTERNAL
OSCILLATOR
Figure 21. Charge Pump Voltage Inverter
Transmitter (Driver) Section
The drivers convert 5 V logic input levels into EIA-232 output
levels. With VCC = +5 V and driving an EIA-232 load, the output voltage swing is typically ± 9 V.
Unused inputs may be left unconnected, as an internal 400 kΩ
pull-up resistor pulls them high forcing the outputs into a low
state. The input pull-up resistors typically source 8 µA when
grounded, so unused inputs should either be connected to VCC
or left unconnected in order to minimize power consumption.
Receiver Section
The receivers are inverting level shifters which accept EIA-232
input levels and translate them into 5 V logic output levels.
The inputs have internal 5 kΩ pull-down resistors to ground and
are also protected against overvoltages of up to ± 25 V. The
guaranteed switching thresholds are 0.4 V minimum and 2.4 V
maximum. Unconnected inputs are pulled to 0 V by the internal
5 kΩ pull-down resistor. This, therefore, results in a Logic 1
output level for unconnected inputs or for inputs connected to
GND.
The receivers have Schmitt trigger input with a hysteresis level
of 0.5 V. This ensures error-free reception for both noisy inputs
and for inputs with slow transition times.
ENABLE AND SHUTDOWN
Table II and Table III show the truth tables for the enable and
shutdown control signals. The enable function is intended to
facilitate data bus connections where it is desirable to three state
the receiver outputs. In the disabled mode, all receiver outputs
are placed in a high impedance state. The shutdown function is
intended to shut the device down, thereby minimizing the quiescent current. In shutdown, all transmitters are disabled and all
receivers on the ADM211E are three-stated. On the ADM213E,
receivers R4 and R5 remain enabled in shutdown. Note that the
transmitters are disabled but are not three-stated in shutdown,
so it is not permitted to connect multiple (RS-232) driver outputs together.
The shutdown feature is very useful in battery operated systems
since it reduces the power consumption to 1 µW. During shutdown the charge pump is also disabled. The shutdown control
input is active high on the ADM211E, and it is active low on
the ADM213E. When exiting shutdown, the charge pump is
restarted and it takes approximately 100 µs for it to reach its
steady state operating conditions.
High Baud Rate
C3
C1
S2
S3
S1
The ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
are ruggedized RS-232 line drivers/receivers which operate from
a single +5 V supply. Step-up voltage converters coupled with
level shifting transmitters and receivers allow RS-232 levels to
be developed while operating from a single +5 V supply.
Features include low power consumption, high transmission
rates and compatibility with the EU directive on electromagnetic compatibility. EM compatibility includes protection
against radiated and conducted interference including high
levels of electrostatic discharge.
VCC
The ADM2xxE feature high slew rates permitting data transmission at rates well in excess of the EIA-232-E specifications.
RS-232 levels are maintained at data rates up to 230 kb/s even
under worst case loading conditions. This allows for high speed
data links between two terminals or indeed it is suitable for the
–9–
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
new generation modem standards which requires data rates of
200 kb/s. The slew rate is internally controlled to less than 30 V/µs
in order to minimize EMI interference.
R1
RECEIVER
INPUT
RX
D1
RIN
D2
3V
EN INPUT
0V
Figure 24a. Receiver Input Protection Scheme
tDR
VOH
VOH –0.1V
RECEIVER
OUTPUT
TOUT
RX
VOL +0.1V
TRANSMITTER
OUTPUT
D1
VOL
D2
NOTE:
EN IS THE COMPLEMENT OF EN FOR THE ADM213E
Figure 24b. Transmitter Output Protection Scheme
Figure 22. Receiver-Disable Timing
ESD TESTING (IEC1000-4-2)
IEC1000-4-2 (previously 801-2) specifies compliance testing
using two coupling methods, contact discharge and air-gap
discharge. Contact discharge calls for a direct connection to the
unit being tested. Air-gap discharge uses a higher test voltage
but does not make direct contact with the unit under test. With
air discharge, the discharge gun is moved towards the unit under test developing an arc across the air gap, hence the term airdischarge. This method is influenced by humidity, temperature,
barometric pressure, distance and rate of closure of the discharge
gun. The contact-discharge method while less realistic is more
repeatable and is gaining acceptance in preference to the air-gap
method.
3V
EN INPUT
0V
tER
+3.5V
RECEIVER
OUTPUT
+0.8V
NOTE:
EN IS THE COMPLEMENT OF EN FOR THE ADM213E
Figure 23. Receiver Enable Timing
ESD/EFT Transient Protection Scheme
The ADM2xxE uses protective clamping structures on all inputs
and outputs which clamps the voltage to a safe level and dissipates the energy present in ESD (Electrostatic) and EFT (Electrical Fast Transients) discharges. A simplified schematic of the
protection structure is shown in Figures 24a and 24b. Each
input and output contains two back-to-back high speed clamping diodes. During normal operation with maximum RS-232
signal levels, the diodes have no affect as one or the other is
reverse biased depending on the polarity of the signal. If however the voltage exceeds about ± 50 V, reverse breakdown occurs
and the voltage is clamped at this level. The diodes are large p-n
junctions which are designed to handle the instantaneous current surge which can exceed several amperes.
The transmitter outputs and receiver inputs have a similar protection structure. The receiver inputs can also dissipate some of
the energy through the internal 5 kΩ resistor to GND as well as
through the protection diodes.
The protection structure achieves ESD protection up to
± 15 kV and EFT protection up to ± 2 kV on all RS-232 I-O
lines. The methods used to test the protection scheme are discussed later.
Although very little energy is contained within an ESD pulse,
the extremely fast rise time coupled with high voltages can cause
failures in unprotected semiconductors. Catastrophic destruction can occur immediately as a result of arcing or heating. Even
if catastrophic failure does not occur immediately, the device
may suffer from parametric degradation which may result in
degraded performance. The cumulative effects of continuous
exposure can eventually lead to complete failure.
I-O lines are particularly vulnerable to ESD damage. Simply
touching or plugging in an I-O cable can result in a static discharge that can damage or completely destroy the interface
product connected to the I-O port. Traditional ESD test methods such as the MIL-STD-883B method 3015.7 do not fully
test a products susceptibility to this type of discharge. This test
was intended to test a products susceptibility to ESD damage
during handling. Each pin is tested with respect to all other
pins. There are some important differences between the traditional test and the IEC test:
(a) The IEC test is much more stringent in terms of discharge
( energy. The peak current injected is over four times greater.
(b) The current rise time is significantly faster in the IEC test.
(c) The IEC test is carried out while power is applied to the device.
It is possible that the ESD discharge could induce latch-up in the
device under test. This test therefore is more representative of a
real-world I-O discharge where the equipment is operating normally with power applied. For maximum peace of mind however,
both tests should be performed, therefore, ensuring maximum
protection both during handling and later during field service.
–10–
REV. B
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
HIGH
VOLTAGE
GENERATOR
R1
R2
Table IV. IEC1000-4-2 Compliance Levels
DEVICE
UNDER TEST
C1
ESD TEST METHOD
R2
C1
H. BODY MIL-STD883B
1.5kV
100pF
IEC1000-4-2
330V
150pF
Level
Contact Discharge
kV
Air Discharge
kV
1
2
3
4
2
4
6
8
2
4
8
15
Figure 25. ESD Test Standards
Table V. ADM2xxE ESD Test Results
100
IPEAK – %
90
ESD Test Method
I-O Pins
Other Pins
MIL-STD-883B
IEC1000-4-2
Contact
Air
± 15 kV
± 2.5 kV
± 8 kV
± 15 kV
FAST TRANSIENT BURST TESTING (IEC1000-4-4)
36.8
10
tDL
tRL
TIME t
Figure 26. Human Body Model ESD Current Waveform
100
90
IEC1000-4-4 (previously 801-4) covers electrical fast-transient/
burst (EFT) immunity. Electrical fast transients occur as a
result of arcing contacts in switches and relays. The tests simulate the interference generated when for example a power relay
disconnects an inductive load. A spark is generated due to the
well known back EMF effect. In fact the spark consists of a
burst of sparks as the relay contacts separate. The voltage appearing on the line, therefore, consists of a bust of extremely fast transient impulses. A similar effect occurs when switching on
fluorescent lights.
IPEAK – %
The fast transient burst test defined in IEC1000-4-4 simulates
this arcing and its waveform is illustrated in Figure 28. It consists of a burst of 2.5 kHz to 5 kHz transients repeating at
300 ms intervals. It is specified for both power and data lines.
V
10
0.1 TO 1ns
TIME t
30ns
t
60ns
300ms
Figure 27. IEC1000-4-2 ESD Current Waveform
V
The ADM2xxE family of products are tested using both the
above mentioned test methods. All pins are tested with respect
to all other pins as per the MIL-STD-883B specification. In
addition all I-O pins are tested as per the IEC test specification.
The products were tested under the following conditions:
(a) Power-On—Normal Operation
(b) Power-On—Shutdown Mode
(c) Power-Off
50ns
t
0.2/0.4ms
Figure 28. IEC1000-4-4 Fast Transient Waveform
There are four levels of compliance defined by IEC1000-4-2.
The ADM2xxE family of products meet the most stringent
compliance level for both contact and for air-gap discharge. This
means that the products are able to withstand contact discharges in
excess of 8 kV and air-gap discharges in excess of 15 kV.
REV. B
15ms
5ns
–11–
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
Testing for immunity involves irradiating the device with an EM
field. There are various methods of achieving this including use
of anechoic chamber, stripline cell, TEM cell, GTEM cell. A
stripline cell consists of two parallel plates with an electric field
developed between them. The device under test is placed within
the cell and exposed to the electric field. There are three severity
levels having field strengths ranging from 1 V to 10 V/m. Results
are classified in a similar fashion to those for IEC1000-4-4.
Table VI.
Level
V Peak (kV)
PSU
V Peak (kV)
I-O
1
2
3
4
0.5
1
2
4
0.25
0.5
1
2
1. Normal operation.
A simplified circuit diagram of the actual EFT generator is
illustrated in Figure 29.
The transients are coupled onto the signal lines using an EFT
coupling clamp. The clamp is 1 m long and it completely surrounds the cable providing maximum coupling capacitance
(50 pF to 200 pF typ) between the clamp and the cable. High
energy transients are capacitively coupled onto the signal lines.
Fast rise times (5 ns) as specified by the standard result in very
effective coupling. This test is very severe since high voltages are
coupled onto the signal lines. The repetitive transients can often
cause problems where single pulses don’t. Destructive latch-up
may be induced due to the high energy content of the transients.
Note that this stress is applied while the interface products are
powered up and are transmitting data. The EFT test applies
hundreds of pulses with higher energy than ESD. Worst case
transient current on an I-O line can be as high as 40A.
2. Temporary degradation or loss of function which is selfrecoverable when the interfering signal is removed.
3. Temporary degradation or loss of function which requires
operator intervention or system reset when the interfering
signal is removed.
4. Degradation or loss of function which is not recoverable due
to damage.
The ADM2xxE family of products easily meets Classification 1
at the most stringent (Level 3) requirement. In fact field strengths
up to 30 V/m showed no performance degradation and error-free
data transmission continued even during irradiation.
Table VII. Test Severity Levels (IEC1000-4-3)
Test results are classified according to the following:
Level
Field Strength
V/m
1. Normal performance within specification limits.
1
2
3
1
3
10
2. Temporary degradation or loss of performance which is selfrecoverable.
3. Temporary degradation or loss of function or performance
which requires operator intervention or system reset.
EMISSIONS/INTERFERENCE
EN55 022, CISPR22 defines the permitted limits of radiated
and conducted interference from Information Technology (IT)
equipment. The objective of the standard is to minimize the
level of emissions both conducted and radiated.
4. Degradation or loss of function which is not recoverable due
to damage.
The ADM2xxE have been tested under worst case conditions
using unshielded cables and meet Classification 2. Data transmission during the transient condition is corrupted but it may
be resumed immediately following the EFT event without user
intervention.
For ease of measurement and analysis, conducted emissions are
assumed to predominate below 30 MHz and radiated emissions
are assumed to predominate above 30 MHz.
CONDUCTED EMISSIONS
HIGH
VOLTAGE
SOURCE
RC
CC
RM
L
CD
50V
OUTPUT
ZS
Figure 29. IEC1000-4-4 Fast Transient Generator
IEC1000-4-3 RADIATED IMMUNITY
IEC1000-4-3 (previously IEC801-3) describes the measurement
method and defines the levels of immunity to radiated electromagnetic fields. It was originally intended to simulate the electromagnetic fields generated by portable radio transceivers or
any other device which generates continuous wave radiated
electromagnetic energy. Its scope has since been broadened to
include spurious EM energy which can be radiated from fluorescent lights, thyristor drives, inductive loads, etc.
This is a measure of noise which gets conducted onto the line
power supply. Switching transients from the charge pump which
are 20 V in magnitude and containing significant energy can
lead to conducted emissions. Other sources of conducted emissions can be due to overlap in switch on-times in the charge
pump voltage converter. In the voltage doubler shown below, if
S2 has not fully turned off before S4 turns on, this results in a
transient current glitch between VCC and GND which results in
conducted emissions. It is therefore important that the switches
in the charge pump guarantee break-before-make switching
under all conditions so that instantaneous short circuit conditions do not occur.
The ADM2xxE has been designed to minimize the switching
transients and ensure break-before-make switching thereby
minimizing conducted emissions. This has resulted in the level
of emissions being well below the limits required by the specification. No additional filtering/decoupling other than the recommended 0.1 µF capacitor is required.
–12–
REV. B
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
Conducted emissions are measured by monitoring the line
power supply. The equipment used consists of a LISN (Line
Impedance Stabilizing Network) which essentially presents a
fixed impedance at RF, and a spectrum analyzer. The spectrum
analyzer scans for emissions up to 30 MHz and a plot for the
ADM211E is shown in Figure 32.
S3
S1
VCC
V+ = 2V CC
C1
S2
C3
S4
VCC
GND
INTERNAL
OSCILLATOR
Figure 30. Charge Pump Voltage Doubler
RADIATED EMISSIONS
Radiated emissions are measured at frequencies in excess of
30 MHz. RS-232 outputs designed for operation at high baud
rates while driving cables can radiate high frequency EM energy.
The reasons already discussed which cause conducted emissions
can also be responsible for radiated emissions. Fast RS-232
output transitions can radiate interference, especially when
lightly loaded and driving unshielded cables. Charge pump
devices are also prone to radiating noise due to the high frequency oscillator and high voltages being switched by the charge
pump. The move towards smaller capacitors in order to conserve board space has resulted in higher frequency oscillators
being employed in the charge pump design. This has resulted in
higher levels of emission, both conducted and radiated.
The RS-232 outputs on the ADM2xxE products feature a controlled slew rate in order to minimize the level of radiated emissions, yet are fast enough to support data rates up to 230 kBaud.
RADIATED NOISE
ø1
DUT
ø2
TURNTABLE
ADJUSTABLE
ANTENNA
TO
RECEIVER
SWITCHING GLITCHES
Figure 33. Radiated Emissions Test Setup
Figure 34 shows a plot of radiated emissions vs. frequency. This
shows that the levels of emissions are well within specifications
without the need for any additional shielding or filtering components. The ADM2xxE was operated at maximum baud rates
and configured as in a typical RS-232 interface.
Figure 31. Switching Glitches
80
70
LIMIT
60
Testing for radiated emissions was carried out in a shielded
anechoic chamber.
dBmV
50
80
40
70
30
60
20
dBmV
50
10
0
0.3
0.6
3
6
1
LOG FREQUENCY – MHz
18
LIMIT
40
30
30
20
Figure 32. Conducted Emissions Plot
10
0
START 30.0 MHz
STOP 200.0 MHz
Figure 34. Radiated Emissions Plot
REV. B
–13–
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
24-Lead DIP (N-24)
1.275 (32.30)
1.125 (28.60)
24
13
1
12
0.280 (7.11)
0.240 (6.10)
0.325 (8.25)
0.300 (7.62) 0.195 (4.95)
0.115 (2.93)
0.060 (1.52)
0.015 (0.38)
PIN 1
0.210
(5.33)
MAX
0.200 (5.05)
0.125 (3.18)
0.150
(3.81)
MIN
0.022 (0.558)
0.014 (0.356)
0.100 (2.54)
BSC
0.070 (1.77)
0.045 (1.15)
0.015 (0.381)
0.008 (0.204)
SEATING
PLANE
24-Lead SOIC (R-24)
28-Lead SOIC (R-28)
0.6141 (15.60)
0.5985 (15.20)
12
PIN 1
0.0118 (0.30)
0.0040 (0.10)
0.1043 (2.65)
0.0926 (2.35)
0.0500
(1.27)
BSC
8°
0.0192 (0.49)
0°
SEATING
0.0125
(0.32)
0.0138 (0.35) PLANE
0.0091 (0.23)
0.0291 (0.74)
x 45°
0.0098 (0.25)
15
1
14
PIN 1
0.1043 (2.65)
0.0926 (2.35)
0.0500 (1.27)
0.0157 (0.40)
0.0118 (0.30)
0.0040 (0.10)
0.0500
(1.27)
BSC
24-Lead SSOP (RS-24)
0.078 (1.98) PIN 1
0.068 (1.73)
0.008 (0.203) 0.0256
(0.65)
0.002 (0.050) BSC
8°
0.0192 (0.49)
0°
SEATING 0.0125 (0.32)
0.0138 (0.35)
PLANE 0.0091 (0.23)
0.0500 (1.27)
0.0157 (0.40)
0.407 (10.34)
0.397 (10.08)
0.07 (1.78)
0.066 (1.67)
8°
0.015 (0.38)
0°
SEATING 0.009 (0.229)
0.010 (0.25) PLANE
0.005 (0.127)
15
1
14
0.212 (5.38)
0.205 (5.21)
28
0.311 (7.9)
0.301 (7.64)
12
0.212 (5.38)
0.205 (5.207)
13
0.311 (7.9)
0.301 (7.64)
1
0.0291 (0.74)
x 45°
0.0098 (0.25)
28-Lead SSOP (RS-28)
0.328 (8.33)
0.318 (8.08)
24
0.4193 (10.65)
0.3937 (10.00)
1
28
0.2992 (7.60)
0.2914 (7.40)
13
0.4193 (10.65)
0.3937 (10.00)
24
0.2992 (7.60)
0.2914 (7.40)
0.7125 (18.10)
0.6969 (17.70)
0.07 (1.79)
0.066 (1.67)
0.078 (1.98) PIN 1
0.068 (1.73)
0.037 (0.94)
0.022 (0.559)
0.008 (0.203) 0.0256
(0.65)
0.002 (0.050) BSC
–14–
0.015 (0.38)
0.010 (0.25)
SEATING 0.009 (0.229)
PLANE
0.005 (0.127)
8°
0°
0.03 (0.762)
0.022 (0.558)
REV. B
ADM206E/ADM207E/ADM208E/ADM211E/ADM213E
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
24-Lead TSSOP (RU-24)
13
0.256 (6.50)
0.246 (6.25)
0.177 (4.50)
0.169 (4.30)
24
1
12
0.006 (0.15)
0.002 (0.05)
SEATING
PLANE
C3401–2.5–8/98
0.311 (7.90)
0.303 (7.70)
PIN 1
0.0433
(1.10)
MAX
0.0256 (0.65)
BSC
0.0118 (0.30)
0.0075 (0.19)
0.0079 (0.20)
0.0035 (0.090)
8°
0°
0.028 (0.70)
0.020 (0.50)
28-Lead TSSOP (RU-28)
0.386 (9.80)
0.378 (9.60)
15
0.256 (6.50)
0.246 (6.25)
0.177 (4.50)
0.169 (4.30)
28
1
14
PIN 1
0.006 (0.15)
0.002 (0.05)
0.0256 (0.65) 0.0118 (0.30)
BSC
0.0075 (0.19)
0.0079 (0.20)
0.0035 (0.090)
8°
0°
0.028 (0.70)
0.020 (0.50)
PRINTED IN U.S.A.
SEATING
PLANE
0.0433
(1.10)
MAX
REV. B
–15–
–16–