BEL SRBA

NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input
SRBA-03F1Ax
•
0.75 Vdc - 3.63 Vdc/3 A Output
RoHS Compliant
•
Non-Isolated
Rev.A
OCP/SCP
•
High Efficiency
•
Remote On/Off
•
High Power Density
•
Wide Trim Range
•
Fixed Frequency (300 kHz)
•
Under-voltage Lockout (UVLO)
•
Converter Can Sink and Source
Current
Description
The Bel SRBA-03F1Ax modules are a series of non-isolated dc/dc converters that deliver up to 3 A of output
current with full load efficiency of 94% at 3.3 Vdc output. These modules provide precisely regulated voltage
programmable via external resistor from 0.75 Vdc to 3.63 Vdc over a wide range of input voltage (2.4 Vdc - 5.5
Vdc). The open-frame construction and small footprint enable designers to develop cost and space-efficient
solutions. Standard features include remote On/Off, over current protection, short circuit protection, undervoltage lockout, over temperature protection and programmable output voltage.
Part Selection
Output Voltage
0.75 V - 3.63 V
1
Input
Voltage
Max. Output
Current
Max. Output
Power
Typical
Efficiency
Model Number
Active Low
Model Number
Active High
2.4 V - 5.5 V
3A
10 W
94%
SRBA-03F1AL
SRBA-03F1A0
Notes: 1. These modules use a buck topology, so the output voltages must be 0.5 V less than the input voltage.
2. Add “G” to the end of the Model Number to indicate Tray Packaging.
3. All part numbers above indicate RoHS 6. Change the second letter "R" to "7" for RoHS 5 part numbers.
Absolute Maximum Ratings
Min
Typ
Max
Input Voltage (continuous)
Parameter
-0.3 V
-
5.8 V
Output Enable Terminal Voltage
-0.3 V
-
5.5 V
Ambient Temperature
-40 °C
-
85 °C
Storage Temperature
-55 °C
-
125 °C
Notes
Note: All specifications are typical at 25 °C unless otherwise stated.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel 201-432-0463 • Fax 201-432-9542 • www.belfuse.com
NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input
0.75 Vdc - 3.63 Vdc/3 A Output
Input Specifications
Parameter
Input Voltage
Input Current (full load)
Min
2.4 V
Typ
-
Max
5.5 V
Notes
Vo, set ≤ Vin-0.5 V
Vo=3.3 V
Vo=2.5 V
Vo=2.0 V
Vo=1.8 V
Vo=1.5 V
Vo=1.2 V
Vo=0.75 V
-
2.11 A
1.61 A
1.32 A
1.20 A
1.01 A
0.83 A
0.55 A
-
Vo=3.3 V
Vo=0.75 V
-
32 mA
20 mA
4 mA
60 mA
18 mA
-
I t Inrush Current Transient
-
-
0.04 A s
Turn-on Voltage Threshold
Turn-off Voltage Threshold
1.7 V
2.05 V
2.0 V
2.4 V
-
Input Current (no load)
Remote Off Input Current
Input Reflected Ripple Current (pk-pk)
Input Reflected Ripple Current (rms)
2
Tested with simulated source
impedance of 1 uH, 5 Hz to 20 MHz.
2
Note: All specifications are typical at nominal input, full load at 25°C unless otherwise stated.
Output Specifications
Parameter
Output Voltage Set Point
Min
-2%Vo,set
Typ
-
Max
2%Vo,set
Output Voltage Set Point
-3%Vo,set
-
3%Vo,set
0.7525 V
-
3.63 V
-
0.2%Vo,set
0.2%Vo,set
-
-
0.4%Vo,set
-
0A
4A
-
3A
9.5 A
Short Circuit Surge Transient
-
0.32 A s
-
Ripple and Noise (pk-pk)
-
30 mV
50 mV
Ripple and Noise (rms)
-
10 mV
15 mV
Turn on Time
Overshoot at Turn on
Output Capacitance
-
8 mS
-
12 mS
3%
0 uF
0 uF
-
1000 uF
3000 uF
-
150 mV
-
-
40 uS
150 mV
40 uS
-
Adjustment Range Selected by External
Resistor or Voltage
Load Regulation
Line Regulation
Regulation Over Temperature
(-40 °C to +85 °C)
Output Current
Current Limit Threshold
ESR ≥ 1mohm
ESR ≥ 10mohm
2
Notes
Vin=5 V, 50% full load
Over all operating input voltage,
resistive load and temperature
conditions until end of life.
Io=Iomin to 50% Iomax
Vin=Vinmin to Vinmax
Tested with 0-20 MHz, with
10 uF tantalum capacitor & 1 uF/
10 V ceramic capacitor at the
output
Transient Response
50% ~ 100% Max Load
Settling Time
100% ~ 50% Max Load
Settling Time
VO =
0.75 V -3.63 V
di/dt=2.5 A/ uS; Vin=5 V; and
with 10 uF tantalum capacitor &
1 uF/10 V TDK ceramic
capacitor at the output
Note: All specifications are typical at nominal input, full load at 25°C unless otherwise stated.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel 201-432-0463 • Fax 201-432-9542 • www.belfuse.com
NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input
0.75 Vdc - 3.63 Vdc/3 A Output
General Specifications
Parameter
Min
Typ
Max
Notes
-
94%
93%
91%
90%
89%
87%
81.5%
-
250 kHz
300 kHz
350 kHz
-
135 °C
-
0.7525 V
-
3.63 V
Efficiency
Vo=3.3 V
Vo=2.5 V
Vo=2.0 V
Vo=1.8 V
Vo=1.5 V
Vo=1.2 V
Vo=0.75 V
Switching Frequency
Over Temperature Shutdown
Output Voltage Trim Range
MTBF
Measured at Vin=5 V, full load
Calculated Per Bell Core SR-332 (Vin=5
V; Vo=1.8 V, IO = 2.4 A; Ta = 25 °C)
8,798,829 hours
Dimensions
Inches (L × W × H)
Millimeters (L × W × H)
0.8 x 0.45 x 0.27
20.32 x 11.42 x 6.87
Weight
-
5g
-
Note: All specifications are typical at 25 °C unless otherwise stated.
Control Specifications
Parameter
Min
Typ
Max
Signal Low (Unit Off)
-0.2 V
-
0.3 V
Signal High (Unit On)
-
-
Vin, max
Signal Low (Unit On)
-0.2 V
-
0.3 V
Signal High (Unit Off)
1.5 V
-
Vin, max
Notes
Remote On/Off
Active High: SRBA-03F1A0; Remote On/Off
pin open, Unit on.
Active Low: SRBA-03F1AL; Remote On/Off
pin open, Unit on.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel 201-432-0463 • Fax 201-432-9542 • www.belfuse.com
NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input
0.75 Vdc - 3.63 Vdc/3 A Output
Remote Enable Specifications
The SRBA-03F1AL modules feature an enable
pin with negative logic. If not using the enable
pin, leave the pin open (the module will be on).
During logic_high, the module is turned off,
during logic_low, the module is turned on. It inner
circuit impedance is showed as figure.
SRBA-03F1AL
The SRBA-03F1A0 modules feature an enable
pin with Positive logic. If not using the enable pin,
leave the pin open (the module will be on).
During logic_high, the module is turned on,
during logic_low, the module is turned off. It inner
circuit impedance is showed as figure.
SRBA-03F1A0
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel 201-432-0463 • Fax 201-432-9542 • www.belfuse.com
NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input
0.75 Vdc - 3.63 Vdc/3 A Output
Output Trim Equations
A: Equation for calculating the trim resistor (in kΩ) given the desired adjusted voltage (Vadj) is shown below.
The Trim Up resistor should be connected between the Trim pin and Ground.
Table 1
Vo (V)
0.7525
1.2
1.5
1.8
2.0
2.5
3.3
Vout
Module
200
Trim
Rtrim
GND
Rtrim vs.Output Voltage
180
Rtrim (KΩ)
Open
41.973
23.077
15.004
11.779
6.947
3.16
160
140
Rtrim(kΩ)
Rtrim
21.07
=
− 5.11
Vadj − 0.7525
120
100
80
60
40
20
0
0.75 1.04 1.33 1.61 1.9 2.19 2.48 2.77 3.05 3.34 3.63
Output Voltage(V)
B: Equation for calculating the trim voltage (in V) given the desired adjusted voltage (Vadj) is shown below. The
Trim Up voltage should be connected between the Trim pin and Ground.
Vtrim = 0.7 − 0.1698 × (Vadj − 0.7525)
0.7
Table 2
Module
Trim
Vtrim
GND
C:
Rset
VO
Rdown
Rup
Trim
21.07
Vo − 0.7525
0.6
0.55
0.5
0.45
0.4
0.35
0.3
0.25
0.2
0.75 1.04 1.33 1.61
1.9
2.19 2.48
Vo(V)
2.77 3.05 3.34 3.63
− 5.11 KΩ
21.07 ⋅Rset − 5.11 ⋅Vm_up⋅Rset + 3.845 ⋅Rset
KΩ
Vm_up⋅Rset + 5.11 ⋅Vm_up − 0.753Rset − 24.915
Margin up value after output voltage is set with Rset
Rset
Rup
Rdown
GND
0.65
Vtrim (V)
Open
0.624
0.5731
0.5221
0.4882
0.4033
0.267
Vtrim(V)
Vo (V)
0.7525
1.2
1.5
1.8
2.0
2.5
3.3
Vout
Vtrim vs. Output Voltage
5.978 ⋅Vm_down ⋅Rset − 4.230 ⋅Rset
KΩ
0.128 ⋅Rset − 0.868 ⋅Vm_down − 0.170 ⋅Vm_down ⋅Rset + 4.230
Margin down value after output voltage is set with Rset
Vm_down ≥ 90%Vo
Note: Output voltage Vo=0.7525 V when Trim pin is not connected.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel 201-432-0463 • Fax 201-432-9542 • www.belfuse.com
NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input
0.75 Vdc - 3.63 Vdc/3 A Output
Efficiency Data
Efficiency Curve
Efficiency Curve
100.0%
100.0%
95.0%
95.0%
90.0%
85.0%
Efficiency
Efficiency
90.0%
4.5 V
5.0 V
5.5 V
80.0%
75.0%
85.0%
4.5 V
5.0 V
5.5 V
80.0%
75.0%
70.0%
70.0%
65.0%
65.0%
60.0%
60.0%
0.6
1.2
1.8
2.4
0.6
3.0
1.2
Vo=3.3 V
3.0
Efficiency Curve
100.0%
95.0%
95.0%
90.0%
90.0%
85.0%
85.0%
Efficiency
Efficiency
2.4
Vo=2.5 V
Efficiency Curve
3.3 V
5.0 V
5.5 V
80.0%
75.0%
3.3 V
5.0 V
5.5 V
80.0%
75.0%
70.0%
70.0%
65.0%
65.0%
60.0%
60.0%
0.6
1.2
1.8
2.4
3.0
0.6
1.2
Output Current (A)
1.8
2.4
3.0
Output Current (A)
Vo=2.0 V
Vo=1.8 V
Efficiency Curve
Efficiency Curve
100.0%
100.0%
95.0%
95.0%
90.0%
90.0%
85.0%
Efficiency
Efficiency
1.8
Output Current (A)
Output Current (A)
2.5 V
3.3 V
5.0 V
80.0%
75.0%
85.0%
2.5 V
3.3 V
5.0 V
80.0%
75.0%
70.0%
70.0%
65.0%
65.0%
60.0%
60.0%
0.6
1.2
1.8
2.4
0.6
3.0
1.2
1.8
2.4
3.0
Output Current (A)
Output Current (A)
Vo=1.5 V
Vo=1.2 V
Efficiency Curve
100.0%
95.0%
Efficiency
90.0%
85.0%
2.5 V
3.3 V
5.0 V
80.0%
75.0%
70.0%
65.0%
60.0%
0.6
1.2
1.8
2.4
3.0
Output Current (A)
Vo=0.75 V
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel 201-432-0463 • Fax 201-432-9542 • www.belfuse.com
NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input
0.75 Vdc - 3.63 Vdc/3 A Output
Thermal Derating Curve
Ripple and Noise Waveforms
5.0 V input, 0.75 V output
5.0 V input, 1.8 V output
5.0 V input, 3.3 V output
Note: Ripple and noise at full load, 0-20 MHz BW, 10 uF/10 V tantalum cap and 1 uF/10 V ceramic cap at the
output, and Ta=25 deg C.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel 201-432-0463 • Fax 201-432-9542 • www.belfuse.com
NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input
0.75 Vdc - 3.63 Vdc/3 A Output
Transient Response Waveforms
Transients 50% to 100% load 0.75 Vdc output
Transients 100% to 50% load 0.75 Vdc output
Transients 50% to 100% load 1.8 Vdc output
Transients 100% to 50% load 1.8 Vdc output
Transients 50% to 100% load 3.3 Vdc output
Transients 100% to 50% load 3.3 Vdc output
Note: Transient response at 5 Vdc input, di/dt=2.5 A/uS, with 10 uF/10 V tantalum cap and 1 uF/10 V ceramic
cap at the output, Ta=25 deg C.
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel 201-432-0463 • Fax 201-432-9542 • www.belfuse.com
NON-ISOLATED DC/DC CONVERTERS
2.4 Vdc - 5.5 Vdc Input
0.75 Vdc - 3.63 Vdc/3 A Output
Mechanical Outline
Recommended Pad Layout
Pin Connections
PAD SIZE: MIN: 0.12"* 0.095" (3.05mm * 2.41mm)
Pin
Function
1
Remote On/Off
2
Vin+
3
N/A
4
Ground
5
Trim
6
Vout+
MAX: 0.135"* 0.11" (3.43mm * 2.79mm)
RoHS Compliance
Complies with the European Directive 2002/95/EC, calling for the elimination of lead and
other hazardous substances from electronic products.
©2007 Bel Fuse Inc. Specifications subject to change without notice. 011707
CORPORATE
FAR EAST
EUROPE
Bel Fuse Inc.
206 Van Vorst Street
Jersey City, NJ 07302
Tel 201-432-0463
Fax 201-432-9542
www.belfuse.com
Bel Fuse Ltd.
8F/ 8 Luk Hop Street
San Po Kong
Kowloon, Hong Kong
Tel 852-2328-5515
Fax 852-2352-3706
www.belfuse.com
Bel Fuse Europe Ltd.
Preston Technology Management Centre
Marsh Lane, Suite G7, Preston
Lancashire, PR1 8UD, U.K.
Tel 44-1772-556601
Fax 44-1772-888366
www.belfuse.com