SC431CSQTR资料

SC431Cx-2
Parameter
Symbol
Condition
Min Typ Max Units
Reference Voltage VREF Temp Deviation Ratio of Change in VREF to Change in VZ Reference Input Current IREF Temperature Deviation Off-State Cathode Current Dynamic Output Impedance Minimum Operating Current
0.37
W
0.78
Thermal Resistance SOT-23-3 SO-8
θJA
336
°C/W
163
Operating Ambient Temperature Range SC431Cx-.5, SC431Cx-1, SC431Cx-2 SC431CxQ
TA
-40 to +85
°C
-40 to +125
Typical Application Circuit(1)(2)
Notes:
1) Set VOUT according to the following equation:
VOUT
=
VREF
1 +
R1 R2

+
IREF
R1
2) Choose the value for R as follows:
VREF VDEV ∆VREF ∆VZ
IREF IREF(DEV) IZ (OFF)
rZ IZ (MIN)
VZ = VREF, IZ = 10mA(1)
VZ = VREF, IZ = 10mA(1)
IZ = 10mA, ∆VZ = 10V to VREF
IZ = 10mA, ∆VZ =30V to 10V
IZ = 10mA(2) R1 = 10kΩ, R2 = ∞,
IZ =10mA(2) VREF = 0V, VZ =30V(3)
2.482
2.495 8
-0.5 -1.0 0.5
0.4
0.04
2.507 17 -2.7 -2.0 4
1.2
0.50
2.470
2.495 8
-0.5 -1.0 0.5
0.4
VREF VDEV ∆VREF ∆VZ IREF
IREF(DEV)
IZ (OFF)
rZ
IZ (MIN)
VZ = VREF, IZ = 10mA(1) VZ = VREF, IZ = 10mA(1) IZ = 10mA, ∆VZ = 10V to VREF IZ = 10mA, ∆VZ =30V to 10V R1 = 10kΩ, R2 = ∞,
Symbol V mA
2008 Semtech Corp.
3
Test Circuit 3 Off-State

POWER MANAGEMENT Pin Configurations
SOT-23-3 (Top View)
SC431
SO-8 (Top View)
Block Diagram
-65 to +150
°C
TLEAD

300
°C
VESD
2
kV
Electrical Characteristics
Unless specified:TA = 25°C. Values in bold apply over full operating ambient temperature range.
Parameter
Symbol
Maximum
Units
Cathode Voltage
Continous Cathode Current
Reference Input Current
Power Dissipation SOT-23-3
at
TA
=
25°C
SO-8
VZ
31
V
IZ
150
mA
IREF
10
mA
PD
SO-8(2)(3)
SC431CS-.5 TRT
0.5% -40°C to +125°C SC431CSKQTR SC431CSKQTRT SC431CSQTR SC431CSQTRT
1.0% -40°C to +85°C SC431CSK-1.TR SC431CSK-1TRT SC431CS-1.TR SC431CS-1.TRT
2.545 30 -2.7 -2.0 4 1.2 0.50 0.50 130
V mV mV/V
µA µA µA Ω µA
Notes: (1) See Test Circuit 1 below. (2) See Test Circuit 2 below. (3) See Test Circuit 3 below.
Also available in Lead-free, fully WEEE and RoHS
compliant.
Applications
Linear Regulators Adjustable Supplies Switching Power Supplies Battery Operated Computers Instrumentation Computer Disk Drives
R1 = 10kΩ, R2 = ∞, IZ = 10mA(2)
R1 = 10kΩ, R2 = ∞, IZ =10mA(2)
VREF = 0V, VZ =30V(3)
f < 1kHz, VZ = VREF, IZ = 130µA to 100mA(1)
VZ
=
V (1) REF
2.445
2.495 15 -0.5 -1.0 0.5 0.4 0.04 0.25
• The maximum limit for R should be such that the cathode current, IZ, is greater than the minimum operating current (130µA) at VIN(MIN).
• The minimum limit for R should be such that IZ does not exceed 150mA under all load conditions, and the instantaneous turn-on value for IZ does not exceed 200mA. Both of the following conditions must be met:
Operating Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering) 10 seconds ESD Rating (Human Body Model)
TJ
-40 to +150
°C
TSTG
Features
Wide operating current range 130µA to 150mA Low dynamic output impedance 0.25 Ω typ. Trimmed bandgap design + 0.5% Alternate for TL1431, TL431, LM431 & AS431 Industrial temperature range Available in SOT-23-3 and SO-8 packages.
0.04
2.520 25 -2.7 -2.0 4
1.2
0.50
V mV mV/V
µA µA µA
IZ
f < 1kHz, = 130µA
tVoZ1=00VmREAF (1)
VZ
=
V (1) REF
0.25 0.50 130
0.25 0.50 Ω 130 µA
2008 Semtech Corp.
2

1

SC431
POWER MANAGEMENT
Absolute Maximum Ratings
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.
The SC431 shunt regulator is available with four voltage tolerances (0.5%, 1.0% and 2.0% over T = -40°C
A
to +85°C and 0.5% over TA = -40°C to +125°C) and two package options (SOT-23-3 and SO-8). This allows the designer the opportunity to select the optimum combination of cost and performance for their application.
Rmin
≥
VIN(max) 200mA
(to limit instantaneous turn-on IZ)
Rmin
≥
VIN(max) − VOUT IOUT(min) +150mA
(to limit I under Z
normal
operating conditions)
Revision: April 23, 2008
Symbol
Ordering Information
Tolerance
0.5%
Ambient Temperature Range -40°C to +85°C
SOT-23-3(1)
SC431CSK-.5 TR
SOT-23-3(1),(3)
SC431CSK-.5TRT
SO-8(2)
SC431CS-.5 TR
SC431Cx-.5, SC431CxQ
SC431Cx-1
Parameter
Symbol
Condition
Min Typ Max Min Typ Max Units
Reference Voltage VREF Temp Deviation Ratio of Change in VREF to Change in VZ Reference Input Current DIREeFvTiaetmiopnerature Off-State Cathode Current Dynamic Output Impedance Minimum Operating Current
SC431
POWER MANAGEMENT
Electrical Characteristics (Cont.)
Unless specified:TA = 25°C. Values in bold apply over full operating ambient temperature range.
SC431
Adjustable Shunt Regulator
POWER MANAGEMENT
Description
The SC431 is a three terminal adjustable shunt regulator with thermal stability guaranteed over temperature. The output voltage can be adjusted to any value from 2.5V (VREF) to 30V with two external resistors. The SC431 has a typical dynamic output impedance of 0.25Ω. Active output circuitry provides a very sharp turn on characteristic, making the SC431 an excellent replacement for zener diodes.
Test Circuits
Test Circuit 1 VZ = VREF
Test Circuit 2 VZ > VREF
Recommended Operating Conditions
Cathode Voltage, VZ Cathode Current, IZ
Min VREF 0.130
Max 30 150