iC-WD, iC-WDS
SWITCH-MODE DUAL 5V REGULATOR
FEATURES
APPLICATIONS
Input voltage 8..30(36)V
dc
Highly efficient step-down regulator
Switching transistor and free-wheeling diode integrated
Adjustment of the regulator cut-off current with external
resistor
Integrated 100kHz oscillator without external components
Switching frequency above the audible range
Internal reference voltages
Two downstream 5V series regulators with 200mA/25mA
output current
Small residual ripple with low capacitances in the
F range
Fault message at overtemperature and undervoltage at
current-limited open-collector output
Shutdown of switching regulator at overtemperature
ESD protection
SO8 package and only few external components
Option: enhanced temperature range of -40..85
C
iC-WDS for input voltages of up to 36V
dc
5V supply from 24V industrial
network
PACKAGES
SO8
BLOCK DIAGRAM
1997
Rev A0
VB (8..30V)
ERROR
+5V (200mA)
RVB
1
220
H
LVH
CVH
4.7
F
1
F
CVCCA
4.7
F
ERROR DETECTION
iC-WD
VREF
SWITCHING REGULATOR VH
OSCILLATOR
THERMAL
LOW VOLTAGE
REFERENCE
REG VCC
REG VCCA
4.7
F
CVCC
NER
1
GND
4
VCCA
7
VCC
6
VH
5
VB
8
VBR
2
VHL
3
+5V (25mA)
SHUTDOWN
iC-Haus GmbH
Tel
+49-6135-9292-0
Integrated Circuits
Fax +49-6135-9292-192
Am Kuemmerling 18, D-55294 Bodenheim
http://www.ichaus.com
iC-WD
SWITCH-MODE DUAL 5V REGULATOR
Rev A0, Page 2/12
DESCRIPTION
The device iC-WD/WDS is a monolithic switching regulator with 2 downstream 5V series regulators. In view
of the high efficiency of the step-down regulator for an input voltage range of 8V to 30(36)V, the iC-WD is
well-suited for applications in industry which require stabilized 5V power supply with minimal power
dissipation and few components.
Switching transistor, free-wheeling diode and oscillator are integrated, limiting the necessary external
elements for the switching regulator to the inductor, the back-up capacitor and one resistor. This resistor
determines the regulator's cut-off current and thus its efficiency in the particular application at hand.
The downstream series regulators have relatively small smoothing capacitors in the
F range and thus
feature a low residual ripple. The output voltages have an internal reference and are specified as 5V
5%
in the entire operating and temperature range. The use of two mutually independent series regulators
makes it possible to isolate the voltage supply of sensitive analog circuits or sensors from the supply for
logic and driver devices.
The chip temperature and the 5V output voltages are monitored. A fault is signalled via the current-limited
open-collector output NER, for example by an LED display or a logical link with other fault signals from the
system. In the event of overtemperature, the switching regulator is switched off to reduce the power
dissipation of the chip.
PACKAGES SO8 to JEDEC Standard
PIN CONFIGURATION SO8
PIN FUNCTIONS
(top view)
No. Name Function
1
NER
Fault Message Output
2
VBR
Pin for shunt
3
VHL
Pin for inductor
4
GND
Ground (reference potential)
5
VH
Intermediate Voltage
6
VCC
5V Output (200mA)
7
VCCA 5V Output (25mA)
8
VB
Supply Voltage
iC-WD
SWITCH-MODE DUAL 5V REGULATOR
Rev A0, Page 3/12
ABSOLUTE MAXIMUM RATINGS
Values beyond which damage may occur; device operation is not guaranteed.
Item
Symbol
Parameter
Conditions
Fig.
Unit
Min.
Max.
G001 VB
Supply Voltage
-0.3
31
V
G002 V(VBR)
Voltage at VBR
-0.3
31
V
G003 I(VHL)
Current in VHL
Peak duration
50
s
-800
800
mA
G004 V(VH)
Voltage at VH
-0.3
8
V
G005 I(VCC)
Current in VCC
-500
4
mA
G006 I(VCCA)
Current in VCCA
-100
4
mA
G007 V(NER)
Voltage at NER
-0.3
31
V
E001 Vd()
ESD Susceptibility
at all pins
MIL-STD-883, Method 3015, HBM
100pF discharged through 1.5k
2
kV
TG1 Tj
Junction Temperature
-40
150
C
TG2 Ts
Storage Temperature
-40
150
C
iC-WDS 36V version
Max. ratings for iC-WD are valid with the following replacements:
G001 VB
Supply Voltage
-0.3
38
V
G002 V(VBR)
Voltage at VBR
-0.3
38
V
G007 V(NER)
Voltage at NER
-0.3
38
V
THERMAL DATA
Operating Conditions: VB= 8..30V (iC-WDS: VB= 8..36V), L
VH
= 220
H, Ri(L
VH
)< 2
, C
VH
= 4.7
F, R
VB
= 1
Item
Symbol
Parameter
Conditions
Fig.
Unit
Min.
Typ.
Max.
T1
Ta
Operating Ambient Temperature
Range
(extended temperature range on
request)
-25
70
C
T2
Rthja
Thermal Resistance
Chip to Ambient
SMD mounting on PCB, without
special cooling
170
K/W
T3
Rthja
Thermal Resistance
Chip to Ambient
SMD mounting on PCB, with approx.
3cm cooling surface (see Demo
Board)
100
K/W
All voltages are referenced to ground unless otherwise noted.
All currents into the device pins are positive; all currents out of the device pins are negative.
iC-WD
SWITCH-MODE DUAL 5V REGULATOR
Rev A0, Page 4/12
ELECTRICAL CHARACTERISTICS
Operating Conditions: VB= 8..30V (iC-WDS: VB= 8..36V)
L
VH
= 220
H, Ri(L
VH
)< 2
, C
VH
= 4.7
F, R
VB
= 1
, Tj= -40..125
C, unless otherwise noted
Item
Symbol
Parameter
Conditions
Tj
Fig.
Unit
C
Min.
Typ.
Max.
Total Device
001
VB
Permissible Supply Voltage
Range
8
30
V
Series Regulator VCC (5V/200mA)
101
VCC
nom
Output Voltage
I(VCC)= -200..0mA
4.75
5.00
5.25
V
102
I(VCC)
Permissible Load Current
-200
0
mA
103
C
VCC
Min. Output Capacity for Stability
4.7
F
104
VCCrip
Residual Ripple
Demo Board: I(VCC)= -200mA,
I(VCCA)= -20mA
27
8
35
mVss
Series Regulator VCCA (5V/25mA)
201
VCCA
nom
Output Voltage
I(VCCA)= -25..0mA
4.75
5.00
5.25
V
202
I(VCCA)
Permissible Load Current
-25
0
mA
203
C
VCCA
Min. Output Capacity for Stability
1
F
204
VCCArip Residual Ripple
Demo Board: I(VCC)= -200mA,
I(VCCA)= -20mA
27
8
30
mVss
Switching Regulator VB, VBR, VHL, VH
301
I0(VB)
Quiescent Current in VB
I(VCC)= 0, I(VCCA)= 0;
VB= 12V
VB= 24V
VB= 30V
27
27
27
4.5
3.0
2.5
mA
mA
mA
302
I(VB)
Current in VB with partial load
I(VCC)+I(VCCA)= -100mA;
VB= 12V
VB= 24V
VB= 30V
27
27
27
72
37
30
mA
mA
mA
303
I(VB)
Current in VB with full load
I(VCC)+I(VCCA)= -200mA;
VB= 12V
VB= 24V
VB= 30V
27
27
27
132
69
55
mA
mA
mA
304
C
VH
Charging Capacitor at VH
4.7
F
305
R(C
VH
)
Series Resistance of C
VH
for
stability
12
306
f0(VHL)
Switching Frequency with no load I(VCC)= 0, I(VCCA)= 0
20
kHz
307
fl(VHL)
Switching Frequency with load
I(VCC)+I(VCCA)= -200mA
27
70
90
120
kHz
kHz
308
V0(VH)
No-load Voltage VH
I(VCC)= 0, I(VCCA)= 0,
VB= 30V
27
7
7.5
V
V
309
Vl(VH)
Voltage VH with load
I(VCC)+I(VCCA)= -200mA,
VB= 8V
27
6
6.3
V
V
310
I
off
Max. Cut-off Current in VHL
VH < Vl(VH), R
VB
= 1
-500
-460
-400
mA
Error Detection NER
401
Toff
Thermal Shutdown Threshold
130
150
C
402
Thys
Thermal Shutdown Hysteresis
3
15
C
403
VCC
VCCA
Relative Undervoltage Threshold
at VCC, VCCA
VCC= VCCnom -VCCoff,
VCCA= VCCAnom -VCCAoff;
200
400
600
mV
404
VCChys
VCCAhys
Undervoltage Hysteresis
100
350
mV
iC-WD
SWITCH-MODE DUAL 5V REGULATOR
Rev A0, Page 5/12
ELECTRICAL CHARACTERISTICS
Operating Conditions: VB= 8..30V (iC-WDS: VB= 8..36V)
L
VH
= 220
H, Ri(L
VH
)< 2
, C
VH
= 4.7
F, R
VB
= 1
, Tj= -40..125
C, unless otherwise noted
Item
Symbol
Parameter
Conditions
Tj
Fig.
Unit
C
Min.
Typ.
Max.
Error Detection NER (continued)
405
Vs(NER) Saturation Voltage lo at NER
I(NER)= 5mA
0.7
V
406
Isc(NER) Short-Circuit Current lo in NER
V(NER)= 1..30V
-40
27
70
125
5
15
12
10
8
21
mA
mA
mA
mA
mA
407
I0(NER)
Collector Off-State Current
in NER
NER= off, V(NER)= 0..30V
0
10
A
iC-WDS 36V version
Characteristics for iC-WD are valid with the following replacements:
001
VB
Permissible Supply Voltage
Range
8
36
V
308
V0(VH)
No-Load Voltage VH
I(VCC)= 0, I(VCCA)= 0, VB= 36V
7.5
V
406
Isc(NER) Short-Circuit Current lo in NER
V(NER)= 1..36V
5
15
21
mA
407
I0(NER)
Collector Off-State Current
in NER
NER= off, V(NER)= 0..36V
0
10
A
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