Document
Bay Linear
Inspire the Linear Power
1.25V Adjustable Shunt Regulator
Description
The B432 is a three terminal adjustable shunt regulator with thermal stability of 50ppm/°C. The output voltage can be adjusted to any value from 1.25V (VREF) to 15V with two external resistors. The B432 is an ideal voltage reference in an isolated feedback circuit for 3.0V switch mode power supplies The B432 shunt regulator is available with three voltage tolerances (0.5%, 1.0% and 2.0%) and three package options (SOT-23-3, TO-92, 8SOIC). This allows the designer the opportunity to select the optimum combination of cost and performance for their application.
B432
Features
• • • • Low voltage operation (down to 1.25V) Wide operating current….1mA to 100mA Trimmed bandgap design ± 0.5% Wide temperature range 0°C to +105°C Available in SOT-23-3, TO-92 , 8SOIC Upgrade for TLV431A & Cross AS432
• •
Applications
• • • • • • Switching Power Supplies Adjustable Power Supplies Linear Regulators Battery Powered Equipment Monitors, TV, VCR Instrumentation
Pin Connection
Ordering Information
Package TO-92 SO-8 SOT-23 0.5% B432AZ B432AM B432AK3
Tolerance 1% B432BZ B432BM B432BK3
2% B432CZ B432CM B432CK3
SOT-23-3 (K3) TO-92 (Z)
1 2 3 Anode
BAY
Ref
Anode Bottom View
Cathode
Ref
Cathode
Top View
Bay Linear, Inc
2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
B432
Absolute Maximum Rating Parameter
Cathode Voltage Continuous Cathode Current Power Dissipation at TA - 25°C SOT-23-3 S0-8 TO-92 Thermal Resistance SOT-23-3 S0-8 TO-92 Operating Junction Temperature Range Storage Temperature Range Lead Temperature (Soldering) 10 seconds ESD Rating (Human Body Model)
Recommended Operating Conditions
Symbol
Vz Iz PD
Maximum
18 100 200 750 775 575 175 160 -40 to +150 -65 to +150 300 2
Units
V mA mW
OJA TJ TSTG TLEAD TESD
°C/W °C °C °C kV
Min
Cathode Voltage, Vz Cathode Current, Iz VREF 1.0
Max
15 100
Symbol
V mA
Electrical Characteristics
Unless specified: T٨ = 25°C. Values in bold apply over full operating ambient temperature. B432 0.5% Parameter Reference Voltage VREF Temp Deviation Ratio of Change in VREF To Change in VZ Reference Input Current IREF Temperature Deviation Off-State Cathode Current Min Operating Current Symbol VREF VDEV Δ VREF ΔVZ IREF IREF(DEV) IZ (OFF) VREF = 0V, VZ =15V(3) IZ(MIN) VZ = VREF(1) 0.05 0.6 500 1 mA Condition VZ = VREF1 IZ = 10mA(1) VZ = VREF1 IZ = 10mA(1) IZ = 10mA,ΔVZ = 15V to VRef R1 = 10kΩ, R2 = ∞, IZ = 10mA(2) R1 = 10kΩ, R2 = ∞, IZ = 10mA(2) Min 1.243 Typ 1.250 2 -1.5 3 0.3 Max 1.257 16 -2.7 6 0.6 Units V mV mV/V µA µA nA
Bay Linear, Inc
2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
B432
Electrical Characteristics
Unless specified: T٨ = 25°C. Values in bold apply over full operating ambient temperature. B432 1% Parameter Reference Voltage VREF Temp Deviation Ratio of Change in VREF To Change in VZ Reference Input Current IREF Temperature Deviation Off-State Cathode Current Min Operating Current Symbol VREF VDEV Δ VREF ΔVZ IREF IREF(DEV) IZ (OFF) VREF = 0V, VZ =15V(3) IZ(MIN) VZ = VREF(1) 0.05 0.6 500 1 mA Condition VZ = VREF1 IZ = 10mA(1) VZ = VREF1 IZ = 10mA(1) IZ = 10mA,ΔVZ = 15V to VRef R1 = 10kΩ, R2 = ∞, IZ = 10mA(2) R1 = 10kΩ, R2 = ∞, IZ = 10mA(2) Min 1.237 Typ 1.250 2 -1.5 3 0.3 Max 1.262 16 -2.7 6 0.6 Units V mV mV/V µA µA nA
Unless specified: T٨ = 25°C. Values in bold apply over full operating ambient temperature. B432 2% Parameter Reference Voltage VREF Temp Deviation Ratio of Change in VREF To Change in VZ Reference Input Current IREF Temperature Deviation Off-State Cathode Current Min Operating Current Symbol VREF VDEV Δ VREF ΔVZ IREF IREF(DEV) IZ (OFF) VREF = 0V, VZ =15V(3) IZ(MIN) VZ = VREF(1) 0.05 0.6 500 1 mA Condition VZ = VREF1 IZ = 10mA(1) VZ = VREF1 IZ = 10mA(1) IZ = 10mA,ΔVZ = 15V to VRef R1 = 10kΩ, R2 = ∞, IZ = 10mA(2) R1 = 10kΩ, R2 = ∞, IZ = 10mA(2) Min 1.225 Typ 1.250 2 -1.5 3 0.3 Max 1.275 16 -2.7 6 0.6 Units V mV mV/V µA µA nA
Bay Linear, Inc
2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556
www.baylinear.com
B432
Vin
10nf
VREF
Vin
Vout
10nf
I (OFF) R1 Iref R
2
IK
VREF
Test Circuit for VKA > VREF Test Circuit for I OFF VO = VKA = VREF x (1 + R1/R2) - IREF x R1
+3.3V
0.1µF
470µF
+12V
PHD 3055E
500Ω
2.7V
140Ω 0.1µF 0.1µF B431L 120Ω
0.1µF
INTEL I 740
1000µF
*If the output voltage has noise, then please add a 0.1µF in between drain and gate of power MOSFET to reduce the noise. Bay Linear, Inc
2478 Armstrong Street, Livermore, CA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556 www.baylinear.com
B432
SOT-23
0.015 - 0.018 (0.381 - 0.457)
0.047 - 0.055 0.083 - 0.098 (1.194 - 1.397) (2.108 - 2.489)
0.035 - 0.040 (0.889 - 1.016) 0.020 - 0.024 (0.508 - 0.610) 0.070 - 0.080 (1.778 - 2.032)
0.110 - 0.120 (2.794 - 3.048)
0.003 - 0.005 (0.076 - 0.127)
0.001 - 0.004 (0.025 - 0.102)
0.030 - 0.041 (0.762 - .