Document
LM350 — 3-Terminal 3 A Positive Adjustable Regulator
September 2014
LM350 3-Terminal 3 A Positive Adjustable Regulator
Features
• Output Adjustable Between 1.2 V and 33 V • Guaranteed 3 A Output Current • Internal Thermal Overload Protection • Load Regulation (Typical: 0.1%) • Line Regulation (Typical: 0.015%/V) • Internal Short-Circuit Current Limit • Output Transistor Safe-Area Compensation
Description
The LM350 is an adjustable 3-terminal positive voltage regulator capable of supplying in excess of 3.0 A over an output voltage range of 1.2 V to 33 V.
TO-220 (Single Gauge)
1
1. Adj 2. Output 3. Input
Ordering Information
Product Number LM350T
Marking LM350
Package
Packing Method Operating Temperature
TO-220 3L (Single Gauge)
Rail
0 to +125°C
© 2002 Fairchild Semiconductor Corporation LM350 Rev. 1.1.0
www.fairchildsemi.com
LM350 — 3-Terminal 3 A Positive Adjustable Regulator
Block Diagram
3 INPUT
+
VREF
_
VOLTAGE REFERENCE
PROTECTION CIRCUITRY
ADJUSTABLE
1
Figure 1. Block Diagram
Q1 Q0
RSC
2
OUTPUT
Absolute Maximum Ratings
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. Values are at TA = 25°C unless otherwise noted.
Symbol
Parameter
Value
Unit
VI - VO TLEAD TOPR TSTG
Input-Output Voltage Differential Lead Temperature (Soldering, 10 sec) Operating Temperature Range Storage Temperature Range
35
V
300
°C
0 to +125
°C
-65 to +150
°C
Thermal Characteristics
Values are at TA = 25°C unless otherwise noted.
Symbol
PD
Power Dissipation
Parameter
Value Internally Limited
Unit W
© 2002 Fairchild Semiconductor Corporation
LM350 Rev. 1.1.0
2
www.fairchildsemi.com
LM350 — 3-Terminal 3 A Positive Adjustable Regulator
Electrical Characteristics
VI - VO = 5 V, IO = 1.5 A, 0°C ≤ TJ ≤ +125°C, PD ≤ PDMAX, unless otherwise specified.
Symbol Rline
Rload
IADJ ΔIADJ REGT VREF Rline Rload STT
IO(MAX)
IL(MIN) VN
RR
Parameter Line Regulation(1)
Load Regulation(1)
Adjustment Pin Current Adjustment Pin Current Change Thermal Regulation Reference Voltage Line Regulation Load Regulation Temperature Stability
Maximum Output Current
Minimum Load Current RMS Noise, %of VOUT Ripple Rejection
Conditions
TA = +25°C, 3 V ≤ VI - VO ≤ 35 V TA = +25°C, 3 V ≤ VI - VO ≤ 35 V, VO ≤ 5V TA = +25°C, 3 V ≤ VI - VO ≤ 35 V, VO ≥ 5V
-
3 V ≤ VI - VO ≤ 35 V, 10 mA ≤ IO ≤ 3 A, PD ≤ PMAX Pulse = 20 ms, TA = +25°C 3 V ≤ VI - VO ≤ 35 V, 10 mA ≤ IO ≤ 3 A, PD ≤ 30 W 3.0 V ≤ VI - VO ≤ 35 V 10 mA ≤ IO ≤ 3.0 A, VO ≤ 5.0 V 10 mA ≤ IO ≤ 3.0 A, VO ≥ 5.0 V TJ = 0°C to +125°C VI - VO ≤ 10 V, PD ≤ PMAX VI - VO = 30 V, PD ≤ PMAX, TA = +25°C
VI - VO = 35 V 10 Hz ≤ f ≤ 10 kHz, TA = +25°C
VO = 10 V, f = 120 Hz, CADJ = 0
VO = 10 V, f = 120 Hz, CADJ = 10 μF
Min.
1.20 3.0 0.25 66
ST
Long-Term Stability
TJ = +125°C
Typ. 0.015
5
0.1 50 0.2 0.002 1.25 0.02 20 0.3 1.0 4.5 1.0 3.5 0.003 65 80
0.3
Max. 0.030
25
Unit %/V
mV
0.5
%
100
μA
5.0
μA
%/W
1.30
V
0.07 %/W
70
mV
1.5
%
%
A
10
mA
%/Vo
dB
1
%/ 1000HR
Note:
1. Regulation is measured at constant junction temperature. Changes in output voltage due to heating effects must be taken into account separately. Pulse testing with low duty cycle is used.
© 2002 Fairchild Semiconductor Corporation
LM350 Rev. 1.1.0
3
www.fairchildsemi.com
LM350 — 3-Terminal 3 A Positive Adjustable Regulator
Typical Performance Characteristics
Figure 2. Load Regulation
Figure 3. Current Limit
Figure 4. Adjustment Pin Current
Figure 5. Dropout Voltage
Figure 6. Temperature Stability
© 2002 Fairchild Semiconductor Corporation LM350 Rev. 1.1.0
Figure 7. Minimum Load Current
www.fairchildsemi.com 4
LM350 — 3-Terminal 3 A Positive Adjustable Regulator
Typical Performance Characteristics (Continued)
Figure 8. Ripple Rejection vs. VO
Figure 9. Ripple Rejection vs. IO
Figure 10. Ripple Rejection vs Frequency
Figure 11. Output Impedan
Figure 12. Line Transient Response
Figure 13. Load Transient Response
© 2002 Fairchild Semiconductor Corporation
LM350 Rev. 1.1.0
5
www.fairchildsemi.com
LM350 — 3-Terminal 3 A Positive Adjustable Regulator
Typical Application(2)
Input
LM350
IN
OUT
ADJ
I1
IADJ
R1 120
CI 0.1uF
R2
Output CO 1uF
Figure 14. Note: 2. CI: CI is required if the regulator is located an appreciable distance from power supply filter.
CO: Output capacitors in the range of 1 μF to 100 μF of aluminum or tantalum electronic are commonly used to provide improved output impedance and rejection of transients.
In operation, the LM350 develops a nominal 1.25 V reference voltage, VREF, between the out.