CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation
of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Electrical Specifications
Unless Otherwise Specified: V
IN
= 264Vms at 50Hz, C1 = 0.05µF, C2 = 470µF, C4 = 1µF, V
OUT
= 5V,
I
OUT
= 50mA, Source Impedance R
1
= 150Ω. Parameters are Guaranteed at the Specific V
IN
and
Frequency Conditions, Unless Otherwise Specified. See test circuit for Component Location.
HV-2405E-5/-9
PARAMETER
Output Voltage (At Preset 5V)
CONDITIONS
V
REF
= 0V
DC
TEMP
+25
o
C
Full
MIN
4.75
4.65
22.8
22.32
-
-
-
-
50
-
-
-
-
TYP
5.0
5.0
24.0
24.0
10
15
-
-
-
24
70
0.02
2
MAX
5.25
5.35
25.2
25.68
20
40
20
40
-
-
-
-
-
UNITS
V
V
V
V
mV
mV
mV
mV
mA
mV
mA
%/
o
C
mA
Output Voltage (At Preset 24V)
V
REF
= 19V
DC
+25
o
C
Full
Line Regulation
80Vrms to 264Vrms
+25
o
C
Full
Load Regulation
(I
OUT
= 5mA to 50mA)
+25
o
C
Full
Output Current
Output Ripple (Vp-p)
Short Circuit Current Limit
Output Voltage TC
Quiescent Current Post Regulator
11V
DC
to 30V
DC
on Pin 2
Full
Full
Full
Full
+25
o
C
4-3
HV-2405E
Application Information
OPERATING CONDITIONS
V
IN
= 50Vrms TO 275Vrms
FREQUENCY = 50Hz to 60Hz
I
OUT
= 0mA to 50mA
V
OUT
= 5V + V
ZI
C2
470µF
C1
0.1µF
R1
100Ω
FUSE
AC HIGH
1
2
3
4
2N2222
HV-2405E
8
7
6
5
Z1
C4
10µF
V
OUT
C3
20pF
R2
220KΩ
AC RETURN
R6
5.6KΩ
Z2
1N5231A
R5
3.3KΩ
C5
0.047
µF
R4
5.6KΩ
R3
3.9KΩ
COMPONENT LIST
FUSE = 1/ 4A
R1 = 100Ω, 5W
R2 = 220kΩ, 1W
R3 = 3.9kΩ, 1/4W
R4 = 5.6kΩ, 1/ 4W
R5 = 3.3Ω, 1/ 4W
R6 = 5.6kΩ, 1/4 W
C1 = 0.1µF, AC RATED
C2 = 470µF, 15V + V
OUT
, ELECTROLYTIC
C3 = 20pF, CERAMIC
C4 = 10µF, V
OUT
+ 10V, ELECTROLYTIC
C5 = 0.047µF, 10V
Z1 = V
OUT
- 5V, 1/4W
Z2 = 5.1V, 1N5231/A OR EQUIVALENT
Q1 = 2N2222 OR EQUIVALENT
FIGURE 1. OFF LINE WORLD-WIDE SUPPLY (I
OUT
≥
50mA)
Off line World Wide Supply (I
OUT
≤
50mA)
Figure 1 shows the recommended application circuit for an
off line world wide supply. The circuit will deliver an output
voltage of 5V to 24V and an output current from 0 to 50mA.
The value of C2 can be reduced for applications requiring
less output current (see section titled “Optimizing Design” for
details). For a basic understanding of the internal operation
of the HV-2405E reference section titled “How the HV-2405E
Works”.
The following is a detailed explanation of this application cir-
cuit:
Basic Operation
When the input voltage goes positive an internal switch
connects pin 8 to pin 2 allowing current to flow through R1 to
charge up C2. When the voltage on C2 reaches a
predetermined voltage the switch opens and the charging of
C2 stops. R1 limits the input current and along with C1
provides a snubber for the internal switch. A linear regulator
takes current from C2 further regulating the voltage and
limiting the ripple at pin 6. The voltage at pin 6 is equal to
V
Z1
+5V. The linear regulator also provides output current
limiting. The capacitor C4 on pin 6 is required for stability of
the output.
Input Current Limiting Circuit
The external components in the shaded area of Figure 1 per-
form two functions. The first is to shut down the HV-2405E in
the presences of a large voltage transients and the second is
to provide input current limiting.
Resistors R2, R3 and capacitor C3 monitor the input voltage
4-4
and turn on Q1 which shuts down the HV-2405E when the
input voltage or the dv/dt is too large. This network antici-
pates the voltage applied to pin 8, since R1 and C1 add
several micro seconds delay, and turns off the HV-2405E
when a predetermined input voltage is exceeded. The differ-
ence between R3/C3 and R1/C1 time constants ensures that
the HV-2405E internal switch opens before the voltage, and
thereby the input current, is allowed to rise to a dangerous
level at pin 8.The input voltage at which the HV-2405E is
turned off, is dependent upon the voltage on C2. The higher
the voltage on C2 the larger the input current that the HV-
2405E can safely turn off. For a detailed explanation of why
the voltage on C2 determines the maximum input current
that the HV-2405E can safely turn off, reference “Start-up” in
section titled “How the HV-2405E Works”.
Input current limiting is provided when the voltage at the
base of Q1 forward biases the base to emitter junction, turn-
ing off the internal switch. The voltage required at the base
to turn on Q1 increases as the voltage on C2 increases the
emitter voltage. When the voltage on C2 is >10V, the emitter
voltage is held constant by Z2 and the maximum input cur-
rent is set by resistors R2, R3, R4 and R5 (see section titled
“Design Equations” for more details).
Operation
The circuit in Figure 1 ensures operation within the SOA of
the HV-2405E by limiting the input current to <500mA when
the voltage on C2 equals zero and <2A when the voltage on
C2 is greater than 10V. The circuits operation is illustrated in
Figure 2 and Figure 3. In Figure 2 the initial current pulse is
approximately 400mA when V
C2
= 0V and gradually
increases to approximately 1.8A when C2 = 10V. Also notice
HV-2405E
that after the 17th line cycle the input current is approxi-
mately 1.4A. At this point C2 is fully charged. The input cur-
rent required to maintain the voltage on C2 is less than the
current to charge it and the circuit has reached steady state
operation. Since the steady state current is less than the
input current limit, the circuit in the shaded area is off and no
longer has any effect.
OFFLINE WORLD-SIDE SUPPLY
I
OUT
= 50mA
Voltage on AC high when input current limit circuit is invoked
(V
C2
= 0V)
I
IN(min)
V
IN1
- V
Pin 8
- V
Pin 2
=
R1
V
IN1
=
R2 + R3
R3
(V
BE
+
R4 (R5 + R6)
R4 + R5 + R6
x I
TRIG
)
(EQ 1)
(EQ. 2)
(EQ. 3)
(EQ. 4)
V
IN1
= 57.41 (0.54 + 3.437kΩ x 60µA) = 42.84V
I
IN(min)
42.84 - 3.5
= 393mA
=
100
V
IN
= 264Vrms
(500V/DIV)
Equation 1 through Equation 4, for the given assumptions,
predict that the initial input current will be limited to 393mA.
The following equations can be used to predict the maximum
input current during start-up.
INPUT CURRENT
(1A/DIV)
I
P
≈
0.8A
V
C2
(10V/DIV)
C2 FULLY CHARGED
Assume: V
C2
> 10V, R1 = 100Ω, R2 = 220kΩ, R3 = 3.9kΩ,
R4 = 5.6kΩ, R5 = 5.6kΩ, R6 = 3.3kΩ, V
BE
= 0.54V, I
TRIG
=
60µA, V
Z
= 5.1V, V
Pin 8
- V
Pin 2
= 6V at high inputs currents,
V
Pin 2
- V
Pin 6
, V
IN2
= Voltage on AC high when input cur-
rent circuit is invoked (V
C2
> 10V).
I
IN(max)
V
IN2
- V
OUT
- (V
Pin 8
- V
Pin 2
) - (V
Pin 2
- V
Pin 6
)
=
R1
V
IN2
=
R2 + R3
R3
(V
BE
R4 R5 x I
TRIG
+ R4 + R5 +
R4
R4 + R5
(EQ. 5)
V
Z2
(EQ. 6)
(EQ. 7)
(EQ. 8)
V
OUT
(5V/DIV)
TIME (50ms/DIV)
FIGURE 2. START UP OPERATION
V
IN2
= 57.41 [0.54 + (2.076kΩ x 60µA) + (0.6292 x 5.1)]
I
IN(max)
=
I
IN(max)
=
222 - V
OUT
-6 -
6
= 2.05A at V
OUT
= 5V
100
222 - V
OUT
-6 -
6
= 1.86A at V
OUT
= 24V
100
Under short circuit operation the maximum voltage on pin 2
is less than 10V and the input current limiting circuit is
invoked. Figure 3 shows that under output short circuit con-
ditions, the input current is limited to about 800mA. The
effects on the output current when the input current limiting
circuit is invoked is illustrated in Figure 6.
OFFLINE WORLD-WIDE SUPPLY
(EQ. 9)
V
IN
= 264Vrms
(500V/DIV)
Equation 5 through Equation 9 predict the maximum input
current will be limited to less than 2.05A. In practice at 5V
operation the current is less than predicted due to the low
bias current through Z2.
Setting The Output Voltage
The circuit shown in Figure 1 provides a regulated 5V to 24V
DC and is set by adjusting the value of Z1. The output volt-
age of the HV-2405E (pin 6) is set by feedback to the sense
pin (pin 5). The output will rise to the voltage necessary to
keep the sense pin at 5V. The output voltage is equal to the
Zener voltage (V
Z1
) plus the 5V on the sense pin. For a 5V
output, pin 5 and pin 6 would be shorted together. The out-
put voltage has the accuracy and tolerance of both the Zener
diode and the band-gap of the HV-2405E (see Figure 16).
The maximum output voltage is limited by Z
B2
to
≈
34V
DC
.
Z
B2
protects the output by ensuring that an overvoltage con-
dition does not exist. Note: the output voltage can also be
set by placing a resistor (1/4W) between pin 5 and pin 6. If a
resistor is placed between pin 5 and pin 6 an additional 1V
per k
Ω
(
±
10%) is added to the 5V output.
INPUT CURRENT
(1A/DIV)
I
P
≈
0.8A
V
C2
(10V/DIV)
V
OUT
(5V/DIV)
TIME (50ms/DIV)
FIGURE 3. SHORT CIRCUIT OPERATION
Design Equations for Input Current Limiting
Initial Start-Up
Assume: V
C2
= 0V, R1 = 100Ω, R2 = 220kΩ, R3 = 3.9kΩ,
R4 = 5.6kΩ, R5 = 3.3kΩ, R6 = 5.6kΩ, V
BE
= 0.54V, I
TRIG
=
60µA, V
Pin 8
- V
Pin 2
= 3.5V at low inputs currents. V
IN1
=
4-5
Optimizing Design
(World-Wide Supply)
Selecting the Storage Capacitor C2
For applications requiring less than 50mA or the full input
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