ETC GM7230

GM7230
3A STEP-DOWN VOLTAGE REGULATOR
Power Management
Features
Description
3.3V, 5V, 12V and Adjustable output versions
The GM7230 series of regulators provide all the active functions for a step-down (buck) switching regulator, and drive
3A load with excellent line and load regulation. GM7230's
are available in fixed output voltages of 3.3V, 5V, 12V, and
a versatile Adjustable output version.
Adjustable version output voltage range 1.23V
to 37V
4% max over line and load conditions
3A output current
Input voltage range up to 40V
These regulators are simple to use and require a minimum
number of external components. Features include internal
frequency compensation and a fixed-frequency oscillator.
The GM7230 series are high-efficiency replacements for
popular three-terminal linear regulators, requiring a smaller
heatsink or even no heatsink.
The GM7230's perform well with standard inductors from
several manufacturers, simplifying the design of switchmode power supplies. The GM7230 series guarantee ±4%
tolerance on output voltage within specified input voltages
and output load conditions, and ±10% on the oscillator frequency.
Requires only 4 external components
High efficiency
TTL shutdown capability, low power standby
mode
Thermal shutdown, current limit protection
Uses standard inductors
150 kHz fixed frequency internal oscillator
External shutdown is included, with 80 µA (typical) standby
current. The output switch has cycle-by-cycle current limiting, as well as thermal shutdown for full protection under
fault conditions.
Application
Pre-regulator for linear regulators
On-card/board switching regulators
High-efficiency step-down buck regulator
Positive to negative converter (buck-boost)
+VIN
1
+ C
IN
GM7230
5.0
5
680 µF ON / OFF
Feedback
4
Output
2
3
GND
L1
68 µH
D1
1N5824
+
COUT
220 µF
5.0V
Regulated
Output
3A Load
GM7230
12V
Unregulated
DC Input
Revision 1, Jun. 2004
TYPICAL APPLICATIONS
www.gammamicro.com
PRELIMINARY
1
GM7230
MARKING INFORMATION & PIN CONFIGURATIONS
TO-220- 5
VIN
Output
Ground
TO-220- 5B
GM7230
GM7230
VVAYWW
VVAYWW
ON/OFF
Feedback
VIN
Output
Ground
2
TO-263-5(D PAK)
GM7230
VVAYWW
ON/OFF
Feedback
VIN
Output
Ground
ON/OFF
Feedback
1 2 3 4 5
V V / VVV= Output Voltage
(33=3.3V , 12=12V, A=Adj)
A
= Assembly Location
Y
= Year
WW
= Work Week
ORDERING INFORMATION
GM7230
Ordering Number
2
Output Voltage
Package
GM7230-ATB5T
Adj
TO-220-5
50 Units / Tube
GM7230-ATB5BT
Adj
TO-220-5B
50 Units / Tube
GM7230-ATA5R
Adj
TO-263-5
800 Units/ Tape & Reel
GM7230-ATA5T
Adj
TO-263-5
50 Units / Tube
GM7230-3.3TB5T
3.3
TO-220-5
50 Units / Tube
GM7230-3.3TB5BT
3.3
TO-220-5B
50 Units / Tube
GM7230-3.3TA5R
3.3
TO-263-5
800 Units/ Tape & Reel
GM7230-3.3TA5T
3.3
TO-263-5
50 Units / Tube
GM7230-5.0TB5T
5.0
TO-220-5
50 Units / Tube
GM7230-5.0TB5BT
5.0
TO-220-5B
50 Units / Tube
GM7230-5.0TA5R
5.0
TO-263-5
800 Units/ Tape & Reel
GM7230-5.0TA5T
5.0
TO-263-5
50 Units / Tube
GM7230-12TB5T
12
TO-220-5
50 Units / Tube
GM7230-12TB5BT
12
TO-220-5B
50 Units / Tube
GM7230-12TA5R
12
TO-263-5
800 Units/ Tape & Reel
GM7230-12TA5T
12
TO-263-5
50 Units / Tube
GM7230-15TB5T
15
TO-220-5
50 Units / Tube
GM7230-15TB5BT
15
TO-220-5B
50 Units / Tube
GM7230-15TA5R
15
TO-263-5
800 Units/ Tape & Reel
GM7230-15TA5T
15
TO-263-5
50 Units / Tube
* TB5B: Bent and Staggered Leads of TO-220 package
** For detail Ordering Number identification, please see last page.
Shipping
GM7230
ABSOLUTE MAXIMUM RATINGS
Rating
Maximum Supply Voltage
-0.3
ON/OFF Pin Input Voltage
Output Voltage to Ground (Steady State)
Power Dissipation
Unit
45
V
V
+25
V
-1.0
V
Internally Limited
-
-65 to + 150
°C
+150
°C
Storage Temperature Range
Maximum Junction Temperature
-40
Operating Temperature Range
Value
Minimum ESD Rating (C=100pF, R=1.5kW)
Lead Temperature (Soldering, 10 sec.)
125
TJ
°C
2
kV
+260
°C
Value
Unit
OPERATING CONDITIONS
Rating
Temperature Range
45
TJ
+125
°C
4.5 to 40
Supply Voltage
V
BLOCK DIAGRAM
ON/ OFF
1.235V
Reference
2.5V
Regulator
Start Up
+
COMP
Current
Limit
COMP
+
2.5V
FEEDBACK
GM
R2
R1=
2.5K
+
AMP
Active Capacitor
3.3V,R2=4.2K
5V,R2=7.6K
12V,R2=21.8K
ADJ,R2=0W
R1=OPEN
+
OP AMP
-
COMP
+
+
Latch
FREQ SHIFT
150kHz
OSC
VIN
+
220 220
mV mV
3A
Switch
Driver
Reset
Thermal
Limit
OUTPUT
GND
GM7230
Current
Source
Bias
3
GM7230
ELECTRICAL CHARACTERISTICS: GM7230-3.3
(Specifications with standard type face are for TJ = 25°C, and those with boldface type apply over full Operating Temperature Range)
Conditions
Parameter
Output Voltage
4.75
VIN 40V, 0.2A ILOAD 3A
VIN = 12V, ILOAD = 3.0A
Efficiency
Symbol
Min
Typ
Max
Unit
VOUT
3.168/3.135
3.3
3.432/3.465
V
h
-
73
-
%
ELECTRICAL CHARACTERISTICS: GM7230-5.0
(Specifications with standard type face are for TJ = 25°C, and those with boldface type apply over full Operating Temperature Range)
Conditions
Parameter
Output Voltage
7V
VIN
40V, 0.2A ILOAD 3A
VIN = 12V, ILOAD = 3.0A
Efficiency
Symbol
Min
Typ
Max
Unit
VOUT
4.800/4.750
5.0
5.200/5.250
V
h
-
80
-
%
ELECTRICAL CHARACTERISTICS: GM7230-12
(Specifications with standard type face are for TJ = 25°C, and those with boldface type apply over full Operating Temperature Range)
Conditions
Parameter
Output Voltage
15V
VIN
40V, 0.2A ILOAD 3A
VIN = 25V, ILOAD = 3.0A
Efficiency
Symbol
Min
Typ
Max
Unit
VOUT
11.52/11.40
12.0
12.48/12.60
V
h
-
90
-
%
ELECTRICAL CHARACTERISTICS: GM7230-ADJ
(Specifications with standard type face are for TJ = 25°C, and those with boldface type apply over full Operating Temperature Range)
Conditions
GM7230
Parameter
4
Feedback Voltage
Efficiency
4.5V
VIN
40V, 0.2A ILOAD 3A
VOUT = 3V
VIN = 12V, ILOAD = 3A, VOUT=3V
Symbol
Min
Typ
Max
Unit
VOUT
1.193/1.180
1.230
1.267/1.280
V
h
-
73
-
%
GM7230
ELECTRICAL CHARACTERISTICS: All Output Voltage Versions
(Specifications with standard type face are for TJ = 25 C, and those with boldface type apply over full Operating Temperature Range.
Unless otherwise specified, VIN= 12V for the 3.3V, 5.0V and ADJ version and VIN= 24V for 12V version. ILOAD = 500 mA)
Conditions
Symbol
Min
Typ
Max
Unit
VFB = 1.3V (Adjustable Version Only)
Ib
-
10
50 / 100
nA
(Note 6)
fo
127/110
150
173 / 173
kHz
IOUT = 3A (Notes 7, 8)
VSAT
-
1.16
1.4 / 1.5
V
Max Duty Cycle (ON)
(Note 8)
DC
100
-
%
Min Duty Cycle (OFF)
(Note 9)
DC
0
-
%
Peak Current (Notes 7, 8)
ICL
3.6 / 3.4
4.5
6.9 / 7.5
A
-
-
50
µA
-
2
30
mA
Parameter
Feedback Bias Current
Oscillator Frequency
Saturation Voltage
Current Limit
(Notes 7, 9, 10)
Output = 0 V
Output Leakage Current
(Notes 10)
Quiescent Current
Standby Quiescent Current
Output = -1V
(Note 9)
IQ
-
5
10
mA
ON/OFF Pin = 5V (OFF) (Note 10)
ISTBY
-
80
200 / 250
µA
-
2
50
50
30
20
-
°C/W
TO-263 Package, Junction to Ambient (Note 14)
qJC
qJA
qJA
qJA
qJA
Low (ON)
VIH
-
1.3
0.6
V
High (OFF)
VIL
2.0
1.3
-
V
VLOGIC = 2.5V (OFF)
IH
-
5
15
µA
VLOGIC = 0.5V (ON)
IL
-
0.02
5
µA
TO-220 or TO-263 Package, Junction to Case
TO-220 Package, Junction to Ambient (Note 11)
Thermal Resistance
TO-263 Package, Junction to Ambient (Note 12)
TO-263 Package, Junction to Ambient (Note 13)
ON/OFF Pin
Logic Input Level
IL
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 resistor into each pin.
Note 3: Typical numbers are at 25°C and represent the most likely norm.
Note 4: All limits guaranteed at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits are
100% production tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC) methods.
All limits are used to calculate Average Outgoing Quality Level (AOQL).
Note 5: External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect switching regulator
system performance. When the GM7230 is used as shown in the Figure 1 test circuit, system performance will be as shown in system parameters section
of Electrical Characteristics.
Note 6: The switching frequency is reduced when the second stage current limit is activated.
Note 7: No diode, inductor or capacitor connected to output pin.
Note 8: Feedback pin removed from output and connected to 0V to force the output transistor switch ON.
Note 9: Feedback pin removed from output and connected to 12V for the 3.3V, 5V, and the ADJ. version, and 15V for the 12V version, to force the output transistor
switch OFF.
Note 10: VIN = 40V.
Note 11: Junction to ambient thermal resistance (no external heat sink) for the TO-220 package mounted vertically, with the leads soldered to a printed circuit board
2
with (1 oz.) copper area of approximately 1 in .
Note 12: Junction to ambient thermal resistance with the TO-263 package tab soldered to a single printed circuit board with 0.5 in2 of (1 oz.) copper area.
Note 13: Junction to ambient thermal resistance with the TO-263 package tab soldered to a single sided printed circuit board with 2.5 in2 of (1 oz.) copper area.
Note 14: Junction to ambient thermal resistance with the TO-263 package tab soldered to a double sided printed circuit board with 3 in2 of (1 oz.) copper area on
2
the GM7230 side of the board, and approximately 16 in of copper on the other side of the p-c board.
GM7230
ON/OFF Pin Input Current
5
GM7230
TEST CIRCUIT AND LAYOUT GUIDELINES
Careful layout is important with any switching regulator. Rapidly switching currents associated with wiring
inductance generate voltage transients which can cause problems. To minimize inductance and ground loops,
the lengths of the leads indicated by heavy lines in Figure 1 below should be kept as short as possible. Singlepoint grounding (as indicated in Figure 1) or ground plane construction should be used for best results. When
using the Adjustable version, place the programming resistors as close as possible to the GM7230, to keep the
sensitive feedback wiring short.
Figure 1(a). Fixed Output Voltage Versions
GM 7230-
+VIN
1
FIXED OUTPUT
Feedback
4
L1
Output
VOUT
2
GND 3
VIN
Unregulated
DC Input
ON/OFF 5
+
+
D1
CIN
COUT
I
Current
meter
K1
CIN - 470 µF, 50V, Aluminum Electrolytic
COUT - 220 µF, 25V, Aluminum Electrolytic
D1 - 5A, 40V Schottky
GM7230
L1 - 68 µH, 3L Electronic Corp. TC-680M-3A-5026
6
GM7230
Power Management
Figure 1(b). Adjustable Output Voltage Versions
Feedback
4
+VIN
GM 7230-ADJ
1
L1
Output
VOUT=5.0V
2
GND 3
+
+
CIN
D1
R2
COUT
R1
VOUT = VREF ( 1 +
L
O
A
D
R2
)
R1
VOUT
R2 = R1 ( V
-1)
REF
where VREF = 1.23V, R1 aproximetly 1kW, 1%
CIN - 470 µF, 50V, Aluminum Electrolytic
COUT - 220 µF, 25V, Aluminum Electrolytic
D1 - 5A, 40V Schottky
L1 - 68 µH, 3L Electronic Corp. TC-680M-3A-5026
R1 - 1k , 1%
VOUT = 5V, R2 = 3.06k , 1%
GM7230
Unregulated
DC Input
ON/ OFF 5
7
GM7230
Typical Performance Characteristics
Figure 3. Switch Current Limit
Figure 2. Switch Saturation Voltage
1.4
5.5
VIN = 12V
SWITCH CURRENT LIMIT (A)
SATURATION VOLTAGE (V)
1.3
1.2
1.1
TJ = - 40°C
1.0
0.9
0.8
25°C
125 °C
VIN = 12V
VOUT = 5V
5.0
4.5
4.0
0.7
3.5
-50
0.6
0
1
2
3
4
SWITCH CURRENT (A)
Figure 4. Dropout Voltage
50
75
100
125
Figure 5. Operating Quiescent Current
SWITCH CURRENT (mA)
INPUT-OUTPUT DIFFERENTIAL (V)
25
24
L = 33 µH
RIND = 0.04W
VOUT = VREG -50mV
1.2
0
JUNCTION TEMPERATURE (°C)
1.6
1.4
-25
ILOAD = 3A
1.0
ILOAD = 1A
0.8
4.5V < VIN < 40V
SWITCH = 0
20
16
Switch ON
12
8
Switch OFF
4
0.6
-50
-25
0
25
50
75
100
0
-50
125
-25
0
25
50
75
100
125
JUNCTION TEMPERATURE (°C)
JUNCTION TEMPERATURE (°C)
Figure 6. Shutdown Quiescent Current
Figure 7. Minimum Operating Supply Voltage
120
5
VON / OFF = 5V
100
8
SUPPLY VOLTAGE (V)
GM7230
CURRENT (µA)
TJ = 25°C
80
TJ = -40°C AND 125°C
60
40
20
0
0
10
20
30
SUPPLY VOLTAGE (V)
40
4
3
2
1
0
-50
VOUT = 1.23V
ILOAD = 120 mA
-25
0
25 50
75 100 125
JUNCTION TEMPERATURE (°C)
GM7230
Typical Performance Characteristics
Figure 8. ON / OFF Pin Current (Sinking)
160
8
7
-40°C
VIN = 40V
TJ 125°C
155
FREQUENCY (kHz)
6
5
4
3
150
145
140
2
135
1
0
0
5
10
15
20
ON / OFF PIN VOLTAGE (V)
25
130
-50
-25
0
25
50
75
100
125
JUNCTION TEMPERATURE (°C)
GM7230
CURRENT(µA)
Figure 9. Switching Frequency
9
GM7230
Inductor Selection by Manufacturer's Part Numbe.
Inductor Value
3L Electronic Corp.
47µH
TC-470M-3A-5026
68µH
TC-680M-3A-5026
100µH
TC-101M-3A-5026
150µH
TC-151M-3A-8026
220µH
TC-221M-3A-8026
330µH
TC-331M-3A-8026
470µH
TC-471M-3A-8026
680µH
TC-681M-3A-8026
1000µH
TC-102M-3A-9426
1500µH
TC-152M-3A-9426
3L Electronic Corp., + 886(2) 86659999
Website : www.3lcoil.com.tw
Capacitor Selection by Manufacturer's Part Number
Capacitor Value
Nippon ChemiI - Con Corp.
100µF
KY50VB100-MH11
220µF
KY50VB220-MJ16
470µF
680µF
KY50VB470-MJ30
KY50VB680-MK30
1000µF
KY50VB1000-ML25
GM7230
Nippon Chemi-Con Corp. , + 81(3)54367628
Website : www.chemi-con.co.jp
10
GM7230
TO-220-5 PACKAGE OUTLINE DIMENSIONS
9.97 ± 0.20
4.50 ± 0.20
9.90 ± 0.20
3.60 ± 0.20
8.0 ± 0.20
8.70
2.80 ± 0.10
7.0
+0.1
1.30 -0.05
3.70 ± 0.20
4.60
28.78 MAX
8.40
P
3°
15.90 ± 0.20
1.50 DP0.20
9.20 ± 0.20
1.30 ± 0.10
1.70
1.2
3°
7.0 ± 0.20
9.20 ± 0.20
3°
13.08 ± 0.20
3-R0.2
5-0.8 ± 0.10
+0.1
0.50 -0.05
2.40 ± 0.20
1.7(TYP)
3°
3°
2 - R 0.3
Unit: mm
10.00 ± 0.20
TO-263-5 PACKAGE OUTLINE DIMENSIONS
9.90
4.50
1.30
15°
0.40
1.20
3°
4.60
1.50 DP0.20
9.20
Pad Layout
0.10
P
4.90
1.70 TYP
(1.70 ± 0.20)
0.80
0.40
17.5
9
2.40
R0.30
0.75
R0.30
3.8
1.7
2.54
0.50
11.5
1.20
3°
2.00
10.0
8.0
7.0
4.40
1.07
1.75
3°
3°
R 0.3
0.90
R 0.45
7.2
Units: mm
9.20
15.30
10.00
GM7230
15.3
11
4.90
Unit: mm
GM7230
TO-220-5B PACKAGE OUTLINE DIMENSIONS
0.18 ± 0.004
4.57 ± 0.1
0.4 ± 0.006
10.16 ± 0.15
0.108 ± 0.006
0.74 ± 0.15
0.05 ± 0.005
1.27 ± 0.1
0.151 ± 0.002
3.84 ± 0.05
C
0.4985 ± 0.0075
12.66 ± 0.2
0.032 ± 0.004
0.81 ± 0.1
0.05 ± 0.005
1.27 ± 0.1
0.965 ± 0.008
24.5 ± 0.2
0.138 ± 0.004
3.5 ± 0.1
0.220
1.700
0.996 ± 0.008
25.3± 0.2
0.105 ± 0.006
2.76± 0.17
0.153 ± 0.0035
3.9 ± 0.1
0.213 ± 0.004
5.4 ± 0.1
0.358 ± 0.008
9.1± 0.2
0.173 ± 0.006
4.4 ± 0.15
0.331 ± 0.006 0.017 ± 0.005
0.42 ± 0.11
8.4 ± 0.15
0.268 ± 0.004
0.68 ± 0.1
(
Inches
)
mm
ORDERING NUMBER
GM 7230 A TB5 T
Shipping
R: Tape & Reel
T: Tube
Gamma Micro.
GM7230
Circuit Type
12
Package
TA5: TO-263-5
TB5: TO-220-5
TB5B: TO-220-5B
Output Voltage
A: Adj, 3.3: 3.3V
5.0: 5.0V, 12: 12V
15: 15V