0.6V Precision
Voltage Reference
POWER MANAGEMENT
Description
The SC4436 is a five terminal device for voltage regula-
tion or over voltage protection of an isolated power sup-
ply with output voltages down to 600mV.
It is intended to be used as a replacement for three
terminal shunt regulators such as SC431L where the
output voltage is too low for the device to function in
conjunction with an opto-isolator. SC4436 achieves this
by having seperate supply and output pins, allowing the
output to sink 20mA of current at voltages ranging from
0.2V to 30V, while the supply pin still has sufficient volt-
age for the device to function. In this way, allowing for a
1.4V drop through an opto-isolator diode, regulation
down to 600mV out can be achieved.
The SC4436 shunt regulator is available with initial ref-
erence voltage accuracies of 0.5% in the space saving
5 lead SC-70.
SC4436
PRELIMINARY
Features
Sub 1V reference (0.6V)
Trimmed bandgap design
Very low operating current (10µA)
Wide supply voltage range (2V to 30V)
Unconditionally stable
Very low temperature coefficient (20 ppm/°C Typ.)
Industrial temperature range
Available in space-saving SC-70 package
Applications
Telecom Power Supplies
Servers and workstation Supplies
Secondary side regulation for very low output
voltage power supplies
Opto driver for very low output voltage
Isolated power supplies
Battery operated applications
Point of use power supplies
Typical Application Circuit
T1
VIN
Primary Side
Controller
Secondary Side
Rectification
and Filtering
Auxillary
Supply
R2
R1
U1
SC4436
R3
C1
OUT
C2
IN
FB
R4
C2 = Open to 100nF
PGND
GND
Revision November 29, 2004
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SC4436
POWER MANAGEMENT
Absolute Maximum Ratings
PRELIMINARY
Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters
specified in the Electrical Characteristics section is not implied.
Parameter
Input Voltage to GND
Output Voltage to GND
Feedback Voltage to GND
PGND to GND
Thermal Impedance, Junction to Ambient
Operating Ambient Temperature Range
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature (Soldering) 10 seconds
Symbol
V
IN
V
IOUT
V
FB
Maximum
-0.3 to 35
-0.3 to 35
-0.3 to Vin+0.3V
-0.3 to +0.3
Units
V
V
V
V
°C/W
°C
°C
°C
°C
θ
J A
T
A
T
J
T
STG
T
LEAD
332
-40 to +105
-40 to +150
-65 to +150
300
Electrical Characteristics
Unless specified: Vin = 3.3V, Iout = 5mA, OUT = FB, Cin = 0.1uF, Cout = 1.0uF, T
A
= T
J
= -40°C to 105°C.
Parameter
IN
Voltage Range
Supply Current
Symbol
Conditions
Min
Typ
Max
Units
V
IN
I
IN
V
IN
= 2V to 30V
I
OUT
= 0.3mA
I
OUT
= 10mA
2
0.5
0.8
30
1
1.5
V
mA
FB
FB Threshold Accuracy
T
A
= +25°C
T
A
= -40°C to +105°C
FB Load Regulation
FB Line Regulation
FB Output Voltage Regulation
FB Input Bias Current
I
FB(BIAS)
I
OUT
= 1mA to 20mA
V
IN
= 2V to 30V
V
OUT
= 0.2V to 18V, I
OUT
= 1mA
V
IN
= 30V
0.597 0.600
0.594
0.6
3.8
0.2
0.2
12
0.603
0.606
6
1
1
+100
mV
mV
mV
nA
V
©
2004 Semtech Corp.
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SC4436
POWER MANAGEMENT
Electrical Characteristics (Cont.)
Unless specified: Vin = 3.3V, Iout = 5mA, OUT = FB, Cin = 0.1uF, Cout = 1.0uF, T
A
= T
J
= -40°C to 105°C.
PRELIMINARY
Parameter
OUT
Voltage Range
Maximum Output Current
Output Leakage Current
Symbol
Conditions
Min
Typ
Max
Units
V
OUT
0.2
V
OUT
= 0.25V, V
IN
= 2V, V
FB
= 0.630V
V
IN
= 30V, V
OUT
= 30V, V
FB
= 0V
T
A
= +25°C
T
A
= +105°C
30
V
mA
I
OUT(MAX)
I
OUT(LEAK)
20
0.001
0.03
0.2
20
0.32
0.1
µA
Dynamic Output Impedance
Dynamic Output Slew rate
Z
OUT
I
OUT
= 1mA to 20mA, f < 1lHz
I
OUT
= 5mA, V
IN
= 3.3V, V
FB
= 0.63V
Ω
V/µs
©
2004 Semtech Corp.
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SC4436
POWER MANAGEMENT
Pin Configuration
TOP VIEW
PRELIMINARY
Ordering Information
Part Number
SC4436RTRT
(1)(2)
P ackag e
5 lead SC70
Temp. Range (T
A
)
-40 to +105
O
C
PGND
GND
OUT
(SC70 5 Lead
)
FB
Note:
(1) Only available in tape and reel packaging
(Suffix ‘TR’ e.g. SC4436RTRT).
(2) Lead free device, fully WEEE and RoHS compliant.
IN
Pin Descriptions
Pin #
1
2
3
4
5
Pin Name
PGND
GND
OUT
IN
FB
Pin Function
Power ground, should be connected to the GND right at the SC4436 IC pin.
Analog ground, should be connected to the PGND right at the SC4436 IC pin.
This is the output pin of the device, essentially an open collector.
This is the input supply pin for the IC., should be bypassed with a 0.1uF capacitor to GND.
This is connected to the non-inverting input of the error amplifier.
Block Diagram
IN
Marking Information
Top Mark
OUT
FB
4436
Bottom Mark
GND
PGND
yyww
yyww = Datecode (Example: 9908)
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©
2004 Semtech Corp.
SC4436
POWER MANAGEMENT
Outline Drawing - SC70-5L
A
e1
N
2X E/2
EI
E
D
PRELIMINARY
DIMENSIONS
INCHES
MILLIMETERS
DIM
MIN NOM MAX MIN NOM MAX
A
A1
A2
b
c
D
E1
E
e
e1
L
L1
N
01
aaa
bbb
ccc
-
-
.043
-
.000
.004
.028 .035 .039
-
.006
.012
-
.003
.009
.075 .079 .083
.045 .049 .053
.083 BSC
.026 BSC
.051
.010 .014 .018
(.017)
5
-
0°
8°
.004
.004
.012
-
-
1.10
-
0.10
0.00
0.70 0.90 1.00
-
0.15
0.30
-
0.22
0.08
1.90 2.00 2.10
1.15 1.25 1.35
2.10 BSC
0.65 BSC
1.30 BSC
0.26 0.36 0.46
(0.42)
5
-
0°
8°
0.10
0.10
0.30
ccc C
2X N/2 TIPS
1
2
e
B
D
aaa C
SEATING
PLANE
A2 A
C
A1
bxN
bbb
C A-B D
GAGE
PLANE
0.15
H
c
L
(L1)
01
SEE DETAIL
SIDE VIEW
NOTES:
1.
2.
3.
4.
A
DETAIL
A
CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
DATUMS -A- AND -B- TO BE DETERMINED AT DATUM PLANE -H-
DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS
OR GATE BURRS.
REFERENCE JEDEC STD MO-203, VARIATION AA.
Land Pattern - SC70-5L
X
DIM
C
G
Z
C
G
P
X
Y
Z
DIMENSIONS
INCHES
MILLIMETERS
(.073)
.039
.026
.016
.033
.106
(1.85)
1.00
0.65
0.40
0.85
2.70
Y
P
NOTES:
1.
THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
©
2004 Semtech Corp.
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