ADDTEK AMC2596-ADJ

AMC2596
150 KHz, 3A STEP DOWN
VOLTAGE REGULATOR
www.addmtek.com
DESCRIPTION
FEATURES
The AMC2596 series are highly integrated step down
voltage regulator capable of driving a 3A load with
extremely regulated output voltages over line & load
regulation. These devices are available in fixed output
voltages of 3.3V. 5V and an adjustable output versions.
These regulators require a minimum number of external
components and are simpler to use by an internal frequency
compensation and a fixed – frequency oscillator.
„
By operating a switching frequency of 150KHz, the
AMC2596 series require smaller sized filter components.
This feature makes the application design more cost effective
than lower frequency switch regulators. A standard 5-lead
TO-220 package with several different lead bend options,
and a 5-lead TO-263 surface mount package is available
„
The AMC2596 series feature a guaranteed ±4%
tolerance of output voltage over input to output load
conditions.
„
APPLICATIONS
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150 KHz fixed frequency internal oscillator
Guaranteed 3A output load current
Input voltage range up to 40V
3.3V, 5V and adjustable output versions
Adjustable version output voltage range, 1.2V
to 37V
±4% max over line and load conditions
Requires only 4 external components
Excellent line and load regulation specifications
Available in TO-220 and TO-263 packages
TTL shutdown capability
Low power standby mode, IQ typically 80 µA
High efficiency
Thermal shutdown and current limit protection
PACKAGE PIN OUT
Portable DVD players
On-card switching regulators
Simple high-efficiency step-down (buck)
regulator
5. Enable
4. FB
3. GND
2. VOUT
1. VIN
5-Pin Plastic TO-220
(Top View)
VOLTAGE OPTIONS
AMC2596-3.3
AMC2596-5.0
AMC2596-ADJ
TA ( °OC )
-40 to 125°C
Note:
Plastic TO-220
5-pin
AMC2596-ADJPF
AMC2596-X.XPF
5-Pin Plastic TO-263
Surface Mount
(Top View)
5. Enable
4. FB
3. GND
2. V OUT
1. V IN
3.3V Fixed
5.0V Fixed
Adjustable Output
P
5. Enable
4. FB
3. GND
2. VOUT
1. VIN
5-Pin Plastic TO-220B
(Top View)
ORDER INFORMATION
Plastic TO-220B
PB
5-pin
AMC2596-ADJPBF
AMC2596-X.XPBF
(Side View)
Plastic TO-263
5-pin
AMC2596-ADJDDF
AMC2596-X.XDDF
DD
1. All surface-mount packages are available in Tape & Reel. Append the letter “T” to part number (i.e. AMC2596-X.XDDFT).
2. The letter “F” is marked for Lead Free process.
Copyright © 2006 ADDtek Corp.
1
DD008_A
-- JUNE 2006
AMC2596
TYPICAL APPLICATION
7V – 40V
DC INPUT
4
FB
1
VIN
AMC2596-X.X
2
VOUT
GND
CIN
680uF
3
L1
33 uH
ENABLE
5
IN5824
OUTPUT
COUT
220uF
Fixed Output Voltage Version
FB 4
7V – 40V
DC INPUT
1
VIN
AMC2596-ADJ
VOUT
GND
3
2
CIN
680uF
OUTPUT
L1
33uH
ENABLE
5
IN5824
R2
COUT
220uF
R1
Adjustable Output Voltage Version
Where VREF = 1.23V, R1 between 1K and 5K
ABSOLUTE MAXIMUM RATINGS
Maximum Supply Voltage
ON/OFF Pin Input Voltage
Feedback Pin Voltage
Output Voltage to Ground (Steady State)
Power dissipation
Storage Temperature Range
ESD Susceptibility --- Human Body Model (Note 2)
(Note 1)
Surface Mount Package--- Vapor Phase (60 sec.)
--- Infrared (10 sec.)
Through Hole Package (Soldering, 10 sec.)
Maximum Junction Temperature, Tj
45V
-0.3≦V≦+25V
-0.3≦V≦+25V
-1V
Internally limited
-65°C to +150°C
2KV
+215°C
+245°C
+260°C
+150°C
Note: Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground.
Currents are positive into, negative out of the specified terminal.
Copyright © 2006 ADDtek Corp.
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AMC2596
THERMAL DATA
P, PB, DD PACKAGE:
Thermal Resistance-Junction to Tab, θJT
Thermal Resistance-Junction to Ambient, θJA
3.0°C /W
45°C /W
Junction Temperature Calculation: TJ = TA + (PD × θ JA). The θJA numbers are guidelines for the thermal performance of the device/pc-board
system. All of the above assume no ambient airflow.
BLOCK DIAGRAM
VIN
FB
1
4
R2*
R1*
GND
Thermal Shutdown
&
Current Limit
150KHz
Oscillator
3
Regulator
With
Enable
5
ENABLE
2
VOUT
Comparator
Driver
Error
Amplifier
1.23V
Reference
Reset
: R2/R1 = 1.7
VOUT = 3.3V
VOUT = 5.0V
: R2/R1 = 3.1
VOUT = Adjustable : R2 = 0, R1 = Open
Copyright © 2006 ADDtek Corp.
3
DD008_A --
JUNE 2006
AMC2596
RECOMMENDED OPERATING CONDITIONS
Temperature Range
Supply Voltage
-40°C≦TJ≦+125°C
4.5V to 40V
ELECTRICAL CHARACTERISTICS
Unless otherwise specified, these specifications apply VIN = 12V, ILOAD = 0.5A and the operating ambient temperatures TJ = 25°C.
Parameter
Output Voltage
Efficiency
Output Voltage
Efficiency
Feedback Voltage
Efficiency
AMC2596-3.3
AMC2596-5.0
AMC2596-ADJ
Feedback Bias Current
Symbol
VOUT
η
VOUT
η
VFB
Conditions
4.75V ≤ VIN ≤ 40V, 0.2A ≤ ILOAD ≤ 3A
7V ≤ VIN ≤ 40V, 0.2A ≤ ILOAD ≤ 3A
4.5V ≤ VIN ≤ 40V, 0.2A ≤ ILOAD ≤ 3A
3.3
3.342
73
4.800
5.0
V
%
5.200
V
80
%
1.193 1.230 1.267
V
%
VIN = 12V, ILOAD = 3A (Note 3)
73
Ib
Adjustable Version Only, VFB =1.3V
10
50
nA
150
173
KHz
1.16
1.4
V
Saturation Voltage
VSAT
IOUT = 3A (Note 5,6)
Max Duty Cycle (ON)
Min Duty Cycle (OFF)
Current Limit
ILIMIT
Output Leakage Current
ILEAK
ENABLE Pin Input Current
3.168
η
(Note 4)
ENABLE Pin Threshold Voltage
Max Units
VIN = 12V, ILOAD = 3A (Note 3)
fOSC
Standby Current
Typ
VIN = 12V, ILOAD = 3A (Note 3)
Oscillator Frequency
Quiescent Current
Min
DC
IQ
127
(Note 8,9)
Peak Current (Note 5,6)
3.6
Output = 0V (Note 5,7)
100
0
4.5
6.9
A
50
µA
30
mA
5
10
mA
80
200
µA
0.6
V
2
Output = -1V (Note 8)
(Note 9)
%
ISTBY
ENABLE pin=5V (OFF) (Note 8)
VIH
Low(Regulator ON)
VIL
High(Regulator OFF)
IH
VLOGIC=2.5V(Regulator OFF)
5
15
µA
IL
VLOGIC=0.5V(Regulator OFF)
0.02
5
µA
2.0
Note 1:Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which
the device is intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions,
see the Electrical Characteristics.
Note 2:The human body model is a 100 pF capacitor discharged through a 1.5K resister into each pin.
Note 3:External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching
regulator system performance. When the AMC2596 is used as shown in the Figure 1 test circuit, system performance will be as shown in
system parameters section of Electrical Characteristics.
Note 4:The switching frequency is reduced when the second stage current limit is activated. The amount of reduction is determined by the severity of
current over-load.
Note 5:No diode, inductor or capacitor connected to output pin.
Note 6:Feedback pin removed from output and connected to 0V to force the output transistor switch ON.
Note 7:Feedback pin removed from output and connected to 12V for the 3.3V, 5V, and the ADJ. version, and 15Vfor the 12V version, to force the
output transistor switch OFF.
Note 8:VIN=40V
Copyright © 2006 ADDtek Corp.
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DD008_A --
JUNE 2006
AMC2596
CHARACTERIZATION CURVES
Typical application circuit, TJ =25°C, unless otherwise specified.
Line
Regulation
Line
Regulation
Output
vs.Temperature
Temperature
OutputVoltage
Voltage v.s
5.04
5.05
5.04
5.03
5.02
5.01
5
4.99
4.98
4.97
4.96
4.95
4.94
4.93
4.92
4.91
4.9
O u t p u t V o lt a g e ( V )
5.035
V O U T (V )
5.03
5.025
5.02
5.015
5.01
5.005
5
-40
-20
0
20
40
60
VIN = 12V, VOUT = 5V
ILOAD = 0.5A
80
-40
VIN (V)
-20
0
20
40
60
80
100
120
Temp (oC)
SaturationVoltage
Voltagev.s
vs.Load
LoadCurrent
Current
Saturation
QuiescentCurrent
Currentv.s
vs.Input
InputVoltage
Voltage
Quiescent
20
3
Q uies c ent Current (uA )
18
2.5
TJ = 125°C
I L O A D (A )
2
1.5
1
TJ = 25°C
0.5
0
0
0.5
1
1.5
2
2.5
VOUT = 5V
16
14
ILOAD = 3A
12
10
8
ILOAD = 200mA
6
4
2
0
3
7
10
15
Saturation Voltage (V)
20
25
30
35
40
Input Voltage (V)
Dropout
Temperature
DropoutVoltage
Voltage v.svs.
Temperature
Standby
Temperature
Standby Current
Current v.svs.Temperature
100
2.4
2.2
VIN = 40V
80
ILOAD = 3A
2
D ro p o u t V o lt a g e ( V )
S t a n d b y C u rr e n t (u A )
90
70
60
50
VIN = 12V
40
30
20
1.8
1.6
1.4
1.2
1
0.8
ILOAD = 0.5A
0.6
0.4
10
0.2
0
0
-40
-20
0
20
40
60
80
100
-40
120
Copyright © 2006 ADDtek Corp.
-20
0
20
40
60
80
100
120
Temp (oC)
Temp (oC)
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DD008_A --
JUNE 2006
AMC2596
CHARACTERIZATION CURVES (continued)
Typical application circuit, TJ =25°C, unless otherwise specified.
Load Transient Response
5V
200mV/ Div
VOUT
1A/ Div
3A
0.5A
ILOAD
Time:100µs/ Div
Copyright © 2006 ADDtek Corp.
6
DD008_A --
JUNE 2006
AMC2596
APPLICATION INFORMATION
Input Capacitors (CIN)
It is required that VIN must be bypassed with at least a 100µF electrolytic capacitor for stability. Also, it is strongly
recommended the capacitor’s leads must be dept short, and located near the regulator as possible.
For low operating temperature range, for example, below -25°C, the input capacitor value may need to be larger. This
is due to the reason that the capacitance value of electrolytic capacitors decreases and the ESR increases with lower
temperatures and age. Paralleling a ceramic or solid tantalum capacitor will increase the regulator stability at cold
temperatures.
Output Capacitors (COUT)
An output capacitor is also required to filter the output voltage and is needed for loop stability. The capacitor should
be located near the AMC2596 using short PC board traces. Low ESR types capacitors are recommended for low
output ripple voltage and good stability. Generally, low value or low voltage (less than 12V) electrolytic capacitors
usually have higher ESR numbers. For example, the lower capacitor values (220µF–1000µF) will yield typically 50
mV to 150 mV of output ripple voltage, while larger-value capacitors will reduce the ripple to approximately 20 mV
to 50 mV.
The amount of output ripple voltage is primarily a function of the ESR (Equivalent Series Resistance) of the output
capacitor and the amplitude of the inductor ripple current (∆IIND).
Output Ripple Voltage = (∆IIND) ×
(ESR of COUT)
Some capacitors called “high-frequency,” “low-inductance,” or “low-ESR.” are recommended to use to further reduce
the output ripple voltage to 10 mV or 20 mV. However, very low ESR capacitors, such as Tantalum capacitors, should
be carefully evaluated.
Output Voltage Ripple and Transients
The output ripple voltage is due mainly to the inductor sawtooth ripple current multiplied by the ESR of the output
capacitor.
The output voltage of a switching power supply will contain a sawtooth ripple voltage at the switcher frequency,
typically about 1% of the output voltage, and may also contain short voltage spikes at the peaks of the sawtooth
waveform.
Due to the fast switching action, and the parasitic inductance of the output filter capacitor, there is voltage spikes
presenting at the peaks of the sawtooth waveform. Cautions must be taken for stray capacitance, wiring inductance,
and even the scope probes used for transients evaluation. To minimize these voltage spikes, shortening the lead length
and PCB traces is always the first thought. Further more, an additional small LC filter (3µH & 180µF) (as shown in
Figure 3) will possibly provide a 10X reduction in output ripple voltage and transients.
AMC2596-ADJ
FB 4
7V – 40V
DC INPUT
L2
1 VIN
GND
CIN
3
3uH
VOUT 2
ENABLE
L1
5
68uH
470uH
COUT
1000µF
R2
50K
R1
1.21K
OUTPUT
C1
180uF
Figure 3. LC Filter for Low Output Ripple
Copyright © 2006 ADDtek Corp.
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DD008_A --
JUNE 2006
AMC2596
APPLICATION INFORMATION (continued)
Inductor Selection
The AMC2596 can be used for either continuous or discontinuous modes of operation. Each mode has distinctively
different operating characteristics, which can affect the regulator performance and requirements.
With relatively heavy load currents, the circuit operates in the continuous mode (inductor current always flowing), but
under light load conditions, the circuit will be forced to the discontinuous mode (inductor current falls to zero for a
period of time). For light loads (less than approximately 300 mA) it may be desirable to operate the regulator in the
discontinuous mode, primarily because of the lower inductor values required for the discontinuous mode.
Inductors are available in different styles such as pot core, toroid, E-frame, bobbin core, et., as well as different core
materials, such as ferrites and powdered iron. The least expensive, the bobbin core type, consists of wire wrapped on a
ferrite rod core. This type of construction makes for an inexpensive inductor, but since the magnetic flux is not
completely contained within the core, it generates more electromagnetic interference (EMI). This EMI can cause
problems in sensitive circuits, or can give incorrect scope readings because of induced voltages in the scope probe.
An inductor should not be operated beyond its maximum rated current because it may saturate. When an inductor
begins to saturate, the inductance decreases rapidly and the inductor begins to look mainly resistive (the DC resistance
of the winding). This will cause the switch current to rise very rapidly. Different inductor types have different
saturation characteristics, and this should be well considered when selecting as inductor.
Catch Diode
This diode is required to provide a return path for the inductor current when the switch is off. It should be located
close to the AMC2596 using short leads and short printed circuit traces as possible. To satisfy the need of fast
switching speed and low forward voltage drop, Schottky diodes are widely used to provide the best efficiency,
especially in low output voltage switching regulators (less than 5V). Besides, fast-Recovery, high-efficiency, or
ultra-fast recovery diodes are also suitable. But some types with an abrupt turn-off characteristic may cause instability
and EMI problems. A fast-recovery diode with soft recovery characteristics is a better choice.
Feedback Connection
For fixed output voltage version, the FB (feedback) pin must be connected to VOUT. For the adjustable version, it is
important to place the output voltage ratio resistors near AMC2596 as possible in order to minimize the noise
introduction.
ENABLE
It is required that the ENABLE must not be left open. For normal operation, connect this pin to a “LOW” voltage
(typically, below 1.6V). On the other hand, for standby mode, connect this pin with a “HIGH” voltage. This pin can
be safely pulled up to +VIN without a resistor in series with it.
Grounding
To maintain output voltage stability, the power ground connections must be low-impedance. For the 5-lead TO-220
and TO-263 style package, both the tab and pin 3 are ground and either connection may be used.
Copyright © 2006 ADDtek Corp.
8
DD008_A --
JUNE 2006
AMC2596
Heat Sink and Thermal Consideration
Although the AMC2596 requires only a small heat sink for most cases, the following thermal consideration is
important for all operation. With the package thermal resistances θJA and θJC, total power dissipation can be estimated
as follows:
PD = (VIN × IQ)+(VOUT / VIN)(ILOAD × VSAT);
When no heat sink is used, the junction temperature rise can be determined by the following:
∆TJ = PD × θJA;
With the ambient temperature, the actual junction temperature will be:
TJ = ∆TJ +TA ;
If the actual operating junction temperature is out of the safe operating junction temperature (typically 125°C), then a
heat sink is required. When using a heat sink, the junction temperature rise will be reduced by the following:
∆TJ = PD × (θJC + θinterface + θHeat sink);
As one can see from the above, it is important to choose an heat sink with adequate size and thermal resistance, such
that to maintain the regulator’s junction temperature below the maximum operating temperature.
Copyright © 2006 ADDtek Corp.
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DD008_A --
JUNE 2006
AMC2596
PACKAGE
Symbol
X.X : Output Voltage Options
3.3 = 3.3V, 5.0 = 5.0V, ADJ= Adjustable
P : Package
P= TO-220, PB= TO-220B, DD= TO-263
2596-X.XP
FYYWW
YYWW: Date Code
YY = Year, WW = Weeks
Example: 0412 means Year 2004, week 12
F: Lead Free
5-Pin Plastic TO-220 (P)
S
B
C
T
A
B
C
D
F
G
J
K
N
R
S
T
F
A
K
D
R
G
N
J
INCHES
MILLIMETERS
MIN
TYP MAX MIN
TYP MAX
0.560
0.650 14.23
16.51
0.380
0.420 9.66
10.66
0.140
0.190 3.56
4.82
0.018
0.035 0.46
0.89
0.140
0.160 3.56
4.06
0.134
3.40
0.012
0.045 0.31
1.14
0.500
0.580 12.70
14.73
0.268 TYP
6.80 TYP
0.080
0.115 2.04
2.92
0.045
0.055 1.14
1.39
0.230
0.270 5.85
6.85
5-Pin Surface Mount TO-263 (DD)
C
A
D
I
B
K
N
M
L
F
E
G
Copyright © 2006 ADDtek Corp.
10
A
B
C
D
E
F
G
I
K
L
M
N
MIN
0.395
0.325
0.171
0.045
0.013
0.029
0.062
0.575
0.090
INCHES
TYP
-
7°
3°
MAX
0.420
0.361
0.181
0.055
0.017
0.035
0.072
0.065
0.635
0.110
MILLIMETERS
MIN
TYP MAX
10.03
10.67
8.25
9.17
4.34
4.59
1.14
1.40
0.330
0.432
0.737
0.889
1.57
1.83
1.65
14.60
16.13
2.29
2.79
7°
3°
DD008_A
-- JUNE 2006
AMC2596
5-Pin Plastic TO-220B (PB)
INCHES
G
A
I
B
f
z1
f1
M
c
c1
d1
z4
H
J
z2
z3
K
d3
d2
e1
N
L
e2
O
z5
e3
Copyright © 2006 ADDtek Corp.
11
MIN TYP MAX
A 0.380 0.401 0.420
B
0.248
c 0.348 0.358 0.368
c1
0.167
d1
0.138
d2
0.154
d3
0.213
e1
0.134
e2
0.268
e3
0.032
f
0.151
f1
0.039
G 0.048 0.05 0.052
H
0.996
I 0.175 0.180 0.185
J
0.965
K
0.105
L 0.164 0.173 0.182
M
0.05
N 0.013 0.015 0.025
O 0.322 0.331 0.340
z1
7°
z2
7°
z3
7°
z4
5°
Z5
5°
MILLIMETERS
MIN TYP MAX
9.65 10.20 10.65
6.30
8.85 9.10 9.35
4.25
3.50
3.90
5.40
3.40
6.80
0.81
3.84
1.00
1.22 1.27 1.32
25.30
4.44 4.57 4.70
24.50
2.67
4.17 4.40 4.63
1.27
0.33 0.381 0.63
8.17 8.40 8.63
7°
7°
7°
5°
5°
DD008_A
-- JUNE 2006
AMC2596
IMPORTANT NOTICE
ADDtek reserves the right to make changes to its products or to discontinue any integrated circuit product or service
without notice, and advises its customers to obtain the latest version of relevant information to verify, before placing
orders, that the information being relied on is current.
A few applications using integrated circuit products may involve potential risks of death, personal injury, or severe
property or environmental damage. ADDtek integrated circuit products are not designed, intended, authorized, or
warranted to be suitable for use in life-support applications, devices or systems or other critical applications. Use of
ADDtek products in such applications is understood to be fully at the risk of the customer. In order to minimize risks
associated with the customer’s applications, the customer should provide adequate design and operating safeguards.
ADDtek assumes to no liability to customer product design or application support. ADDtek warrants the performance of
its products to the specifications applicable at the time of sale.
ADDtek Corp.
9F, No. 20, Sec. 3, Bade Rd., Taipei, Taiwan, 105
TEL: 2-25700299
FAX: 2-25700196
Copyright © 2006 ADDtek Corp.
12
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-- JUNE 2006