Supertex inc.
Supertex inc.
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Doc.# DSFP-SR10
B080613
SR10
Typical Application Circuits
Full-wave Rectification
Half-wave Rectification
Features
►Efficiencies up to 75% at 20mA
►Less than 20mW standby power
►Optional 6.0V, 12V or 24V fixed output
voltage, or adjustable from 6.0V to 28V
►Output current scalable up to 50mA
►120VAC to 240VAC input
►No magnetics
►Inherent short circuit protection
Applications
►Household appliances
►White goods
►Lighting controls
►Utility meters
General Description
The Supertex SR10 is a non-isolated, capacitor-coupled, switched
shunt regulator designed to operate directly from the AC line. Output
voltage can be either fixed at 6.0V, 12V, or 24V using an internal feedback
divider or be adjusted over a 6.0V to 28V range using an external feedback
divider. Output current capability is scalable to 50mA, by selection of the
series coupling capacitor (CS) on the AC line. Standby power can be under
20mW, and efficiencies of 75% are possible depending upon configuration
and degree of transient protection.
All components except for CS are low voltage, easing PCB layout and
alleviating high voltage creepage concerns.
Inherent short circuit protection is afforded by the reactance of the CS
series capacitor, which limits current even with a dead short on the output.
Overcurrent protection (OCP) shuts off the shunt during a line transient.
Refer to application note AN-H65 for further information.
Capacitor-Coupled,
Switched Shunt, (CCSS) Regulator
VOUT
fixed 6V,
12V, 24V
or adj 6 - 28V
COUT
RFB1
RFB2
DOUT
OUT
SR10
PGND
SH
AGND
Output Voltage
Selection
RLIM CS
D6
D12
D24
FB
6V
12V
24V
ex t
RBL
D1 - 4
RTN
CFB
470pF
VIN
90 - 275VAC
50 - 60Hz
VIN
90 - 275VAC
50 - 60Hz
COUT
RFB1
RFB2
DOUT
OUT
SR10
PGND
SH
AGND
Output Voltage
Selection
RLIM CS
6V
12V
24V
ex t
H
N
RBL
DSH
RTN
D6
D12
D24
FB
CFB
470pF
VOUT
fixed 6V,
12V, 24V
or adj 6 - 28V
E ' j
C j
E 3
Absolute Maximum Ratings E j
9 YYWW YY =_Year
851? Male
(3
Typical Thermal Resistance
“
Electrical Characteristics
2
Supertex inc.
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Doc.# DSFP-SR10
B080613
SR10
Absolute Maximum Ratings
Parameter Value
VOUT
, VSH 40V
VFB 5.0V
PGND – AGND ±300mV
IIN(RMS) (SH to PGND) 300mARMS
IDSH (PGND to SH) 300mA
Operating junction temperature -40oC to +125°C
Sym Parameter Min Typ Max Units Conditions
Recommended Operating Conditions
Absolute Maximum Ratings are those values beyond which damage to the device may
occur. Functional operation under these conditions is not implied. Continuous operation
of the device at the absolute rating level may affect device reliability. All voltages are
referenced to device ground.
Pin Configuration
ISH Peak shunt current See Maximum Shunt Current Graph ---
VOUT Output voltage 6.0 - 28 V ---
Electrical Characteristics (Unless otherwise noted, TA = 25°C, Voltages referenced to PGND/AGND pin)
Sym Parameter Min Typ Max Unit Conditions
1
2
3
4
8
7
6
5
SH
PGND
AGND
FB
OUT
D6
D12
D24
8-Lead SOIC
(top view)
8-Lead SOIC
Product Marking
YY = Year Sealed
WW = Week Sealed
L = Lot Number
= “Green” Packaging
YYWW
SR10
LLLL
Note:
1. Guaranteed by design.
Package may or may not include the following marks: Si or
VFB
Feedback threshold
(shunt turn-off)
1.02
1.02
1.20
1.20
1.38
1.38 VTA = 25°C
TA = -40°C to +85°C1
IFB FB input bias current - - ±1.0 µA ---
ADIV
Internal feedback divider ratio: D6
D12
D24
4.85
9.70
19.40
5.00
10.00
20.00
5.15
10.30
20.60
V/V
VOUT = 6.0V
VOUT = 12V
VOUT = 24V
RDIV Internal divider resistance1- 500 - kΩ OUT to AGND
RSH Shunt on resistance - 3.0 7.0 Ω 100mA SH to PGND
100mA PGND to SH
ISH Max shunt current 220 - - mA VSH < 1.2V, 25OC
180 - - 85OC1
VDShunt diode voltage drop - 880 - mV ID = 220mA
Ordering Information
Part Number Package Option Packing
SR10LG-G 8-Lead SOIC 2500/Reel
-G indicates package is RoHS compliant (‘Green’)
Typical Thermal Resistance
Package θja
8-Lead SOIC 101OC/W*
Electrical Characteristics
400 ~50 0 50 10
8
D6
D12
OCP
FB
3
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Doc.# DSFP-SR10
B080613
SR10
Electrical Characteristics (Unless otherwise noted, TA = 25°C, Voltages referenced to PGND/AGND pin)
Sym Parameter Min Typ Max Unit Conditions
Internal Block Diagram
IBIAS Bias current into OUT pin - 220 400 µA 28V applied to the OUT pin
RPD Pull-down resistance on SH 40 50 60 kΩ VSH = 1.5V
VSYNC Voltage at SH to turn the shunt on (SYNC) 2.0 2.3 2.5 V ---
VOCP Voltage at SH to turn the shunt off when on (OCP) 2.0 2.3 2.5 V Shunt on
tFALL Shunt current fall time - 15 - µs 90 - 10%, ISH = 100mA
tOCP OCP response time - 15 - µs Shunt on, ISHUNT < 10mA,
See Figure 3
FB
D24
D12
D6
QSH
Control
DSH
SH OUT
AGNDPGND
Sync &
OCP
SR10
1 8
7
6
5
4
2 3
400kΩ
50kΩ
25kΩ
25kΩ
300
250
200
150
100
50
0
-100 -50 0 50 100 150
ISH(MAX) (mA)
Temperature (
O
C)
Maximum Shunt Current
4
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Doc.# DSFP-SR10
B080613
SR10
Figure 2: Shunt Diode Characteristics
0
100
200
300
400
500
0200 400 600 800 1000
V
D
(mV)
I
D
(mA)
Figure 3: Shunt Turn-off Fall Time
0
ISH
10%
tFALL
90%
Figure 1: OCP Timing
QSH
ON
OFF
VOCP
0V
OCP VOUT
Transient
0V
0A
ISH
Not to scale
10mA
ISAT
tOCP
C C limits input current via finite charge
v "not clamped by the shunt nor by v r Provided by reference.
5
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Doc.# DSFP-SR10
B080613
SR10
Timing
Q
SH
ON
OFF
V
SH
V
REG
V
SYNC
0V
V
OUT
0V
V
OUT
V
SYNC
0V
1 2
3
4
5
6
7
8
9
10
V
OUT
V
SH
if not clamped by the shunt nor by V
OUT
. Provided by reference.
This waveform does not exist in an actual SR10 power supply.
Not to scale.
1. Output voltage decays under load
until ...
2. it hits the regulation point which...
3. turns off the shunt...
4. freeing VSH to rise...
5. until it is clamped by VOUT where...
6. Input current flows to the output,
causing VOUT to rise...
7. until VSH falls below VOUT.
8. When it reaches VSYNC...
9. the shunt is turned on and current
no longer flows to the output.
10. The cycle repeats.
Application Information
The SR10 is a capacitor-coupled, switched shunt regulator.
Capacitor-coupling to the AC line limits input current due to
the finite charge per cycle that can be transferred. Contrast-
ing with a traditional Zener shunt, the switched shunt oper-
ates either fully on or fully off, resulting in low standby power
consumption.
VOUT
COUT
C
S
RTN
VIN
C
S
limits input current via finite charge
transfer per cycle.
No power losses in charge transfer.
Shunt operates either fully on or fully off.
No power-wasting linear operation.
Simplified Schematic
6
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Doc.# DSFP-SR10
B080613
SR10
CS
CS
Tol
6V Output 12V Output 24V Output
Half Full Half Full Half Full
120V
60Hz
240V
50Hz
120V
60Hz
240V
50Hz
120V
60Hz
240V
50Hz
120V
60Hz
240V
50Hz
120V
60Hz
240V
50Hz
120V
60Hz
240V
50Hz
220nF
10% 2.9 5.2 5.7 10.3 2.9 5.2 5.4 10.1 2.7 5.1 4.8 9.6
20% 2.6 4.7 5.0 9.2 2.5 4.6 4.8 9.0 2.4 4.5 4.3 8.5
330nF
10% 4.4 7.9 8.5 15.5 4.3 7.8 8.1 15.1 4.1 7.6 7.2 14.4
20% 3.9 7.0 7.6 13.8 3.8 6.9 7.2 13.4 3.6 6.8 6.4 12.8
470nF
10% 6.3 11.2 12.1 22.0 6.1 11.1 11.5 21.5 5.8 10.8 10.3 20.5
20% 5.6 10.0 10.8 19.6 5.4 9.9 10.2 19.1 5.2 9.6 9.1 18.2
680nF
10% 9.1 16.2 17.5 31.9 8.9 16.0 16.6 31.2 8.4 15.7 14.9 29.7
20% 8.1 14.4 15.6 28.4 7.9 14.3 14.8 27.7 7.5 13.9 13.2 26.4
1.0µF
10% 13.3 23.9 25.7 46.9 13.0 23.6 24.4 45.8 12.4 23.0 21.9 43.7
20% 11.9 21.2 22.9 41.7 11.6 21.0 21.7 40.7 11.0 20.5 19.4 38.8
1.5µF
10% 20.0 35.8 38.6 70.4 19.5 35.4 36.7 68.7 18.6 34.6 32.8 65.5
20% 17.8 31.8 34.3 62.5 17.4 31.4 32.6 61.1 16.5 30.7 29.1 58.2
2.2µF
10% 29.4 52.5 56.6 103.2 28.6 51.9 53.8 100.8 27.2 50.7 48.1 96.1
20% 26.1 46.6 50.3 91.7 25.5 46.1 47.8 89.6 24.2 45.1 42.7 85.4
= Exceeds Recommended Operating Limits
Output current capability (mA)
Output Current Capability
Output current capability is largely a function of capacitor CS
and the input voltage. The following table provides approxi-
mate current capability for various CS values and line volt-
ages. Actual current will be less due to losses. Higher output
voltages slightly reduce output current capability.
CS Table
The following table is based on the previously provided
equations for CS. Actual output current may be less due to
losses (~5% less). AC line voltage is assumed to be 90 -
135VRMS @ 60Hz or 190 - 275VRMS @ 50Hz. Slashed
cells exceed recommended operating conditions for peak
shunt current at 85OC.
For universal 120V and 240V operation choose CS based on
120VAC and make sure that operation at 240VAC does not
fall in a slashed cell. The relevant cells are adjacent to each
other. For example, if 50mA at 12V is needed and full rectifi-
cation used, a CS capacitor of 2.2µF ± 10% provides 53.8mA
at 120VAC (90VAC low line). But at 240VAC, the cell to the
right (240VAC column) is slashed, and universal operation is
not possible. This assumes 120VAC low line is 90VAC and
240VAC high line is 275VAC. For other high/low voltages
use the equations.
EU
r51
EU
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Supertex inc.
www.supertex.com
Doc.# DSFP-SR10
B080613
SR10
FB pin connected to... Output Voltage
D6 6V
D12 12V
D24 24V
External divider VOUT = 1.2V 1 +
R
FB1
RFB2
Note:
A 470pF capacitor from FB pin to AGND pin minimizes the effects of a noisy AC line.
Output Voltage
The output voltage may be adjusted over the range of 6V to
28V using either the SR10’s internal feedback divider or by
using an external divider. The internal divider has taps for
6V, 12V, and 24V which are brought out to pins D6, D12,
and D24 respectively. Connecting the appropriate tap to the
feedback pin (FB) provides the chosen output voltage.
If an output voltage other than that provided by the internal
divider is required, an external feedback divider from VOUT to
the FB pin may be used. The range is from 6V to 28V.
Name Pin Description
SH 1 Shunt
PGND 2 Power ground for the shunt
AGND 3Analog ground for the controller
FB 4 Feedback input
D24 5 Internal feedback divider 24V tap
D12 6 Internal feedback divider 12V tap
D6 7 Internal feedback divider 6.0V tap
OUT 8 Connect to regulator output
Pin Description
Note:
All pins are low voltage.
Additional Information
For a more detailed description or for sample circuits, an application note and a demo board are available.
AH-H65 CCSS Application Note
- Explains the operating principle of the capacitor-coupled, switched shunt regulator
- Provides design equations and guidelines
- Specifies special testing considerations
SR10DB1 SR10 Demo Board
- Jumper-selectable half-wave or full-wave recitfication
- Jumper-selectable output voltage
- Socketed components allow easy optimization
i
iii
7 E E
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TopView
A: r — — 1
;_ fiej fl—K {J
SideView
Supertex inc. does not recommend the use of its products in life support applications, and will not knowingly sell them for use in such applications unless it receives
an adequate “product liability indemnification insurance agreement.” Supertex inc. does not assume responsibility for use of devices described, and limits its liability
to the replacement of the devices determined defective due to workmanship. No responsibility is assumed for possible omissions and inaccuracies. Circuitry and
specifications are subject to change without notice. For the latest product specifications refer to the Supertex inc. (website: http//www.supertex.com)
©2013 Supertex inc. All rights reserved. Unauthorized use or reproduction is prohibited. Supertex inc.
1235 Bordeaux Drive, Sunnyvale, CA 94089
Tel: 408-222-8888
www.supertex.com
8
SR10
Doc.# DSFP-SR10
B080613
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline
information go to http://www.supertex.com/packaging.html.)
8-Lead SOIC (Narrow Body) Package Outline (LG)
4.90x3.90mm body, 1.75mm height (max), 1.27mm pitch
1
8
Seating
Plane
Gauge
Plane
L
L1
L2
EE1
D
eb
AA2
A1
Seating
Plane
A
A
Top View
Side View
View B View B
θ1
θ
Note 1
(Index Area
D/2 x E1/2)
View A-A
h
h
Note 1
Symbol A A1 A2 b D E E1 e h L L1 L2 θ θ1
Dimension
(mm)
MIN 1.35* 0.10 1.25 0.31 4.80* 5.80* 3.80*
1.27
BSC
0.25 0.40
1.04
REF
0.25
BSC
0O5O
NOM - - - - 4.90 6.00 3.90 - - - -
MAX 1.75 0.25 1.65* 0.51 5.00* 6.20* 4.00* 0.50 1.27 8O15O
JEDEC Registration MS-012, Variation AA, Issue E, Sept. 2005.
* This dimension is not specified in the JEDEC drawing.
Drawings are not to scale.
Supertex Doc. #: DSPD-8SOLGTG, Version I041309.
Note:
1. This chamfer feature is optional. A Pin 1 identifier must be located in the index area indicated. The Pin 1 identifier can be: a molded mark/identifier;
an embedded metal marker; or a printed indicator.