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
3 V-3.6 V Input
12 V/0.8 A & 15 V/0.6 A Output
Non-Isolated
Trim Function (option)
High
Efficiency
Allows Burst Mode Operation
Fixed
Frequency
(550
kHz)
Low
Profile
Package
at Low Load Currents
Description
The Bel x7AH-01Cxx0 is part of the low cost non-isolated dc/dc converter series. The modules use a SMD or
SIP package or vertical package for ease of layout and space savings. The output is closely regulated and the
efficiency of 12 V output module is typically 86% at full load. Typical features include allows burst mode
operation at low load currents and trim function (option).
Part Selection
Output
Voltage
Input
Voltage
Max. Output
Current
Max. Output
Power
Typical
Efficiency
Part Number
Surface Mount
Part Number
Vertical Mount
12 V
3 V 3.6 V
0.8 A
9.6 W
86%
S7AH-01CX20
V7AH-01CX20
15 V
3 V 3.6 V
0.6 A
9.0 W
85%
S7AH-01CX50
V7AH-01CX50
Note:
Add "0" suffix at the end of the model number to indicate "Tube Packaging", and "R" for "Reel Packaging",
and "G" for "Tray Packaging".
Absolute Maximum Ratings
Parameter
Min
Typ
Max
Notes
Input Voltage (continuous)
2.8 V
-
4 V
Ambient Temperature
-40
C
-
85
C
Storage Temperature
-40
C
-
125
C
Input Specifications
Parameter
Min
Typ
Max
Notes
Input Voltage
3 V
-
3.6 V
Input Current (no load)
-
15 mA
-
Input Current (full load)
V
O
=12V
V
O
=15V
-
-
-
-
4.3 A
4 A
Input Reflected Ripple Current (pk-pk)
-
100 mA
150 mA
Input Reflected Ripple Current (rms)
-
30 mA
60 mA
With simulated source impedance of
500 nH, 5 Hz to 20 MHz; Use 270
uF/16 V capacitor. with ESR = 0.018
ohm max. at 100KHz at 25
C
I
2
t Inrush Current Transient
-
0.02 A
2
s
0.05 A
2
s
Turn-on Voltage Threshold
-
2.8 V
2.9 V
x7AH-01C Series
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
3 V-3.6 V Input
12 V/0.8 A & 15 V/0.6 A Output
Output Specifications
Parameter
Min
Typ
Max
Notes
Output Voltage Set Point
V
O
=12 V
V
O
=15 V
11.58 V
14.475 V
12 V
15 V
12.42 V
15.525 V
Test condition:
Vin=3.3V, lout=full load
Line Regulation
V
O
=12 V
V
O
=15 V
-
-
20 mV
20 mV
40 mV
40 mV
Load Regulation
V
O
=12 V
V
O
=15 V
-
-
60 mV
75 mV
120 mV
150 mV
Regulation Over Temperature
(-40
C to +85 C)
V
O
=12 V
V
O
=15 V
-
-
45 mV
60 mV
80 mV
100 mV
Output Current
V
O
=12 V
V
O
=15 V
0 A
0 A
-
-
0.8 A
0.6 A
Ripple and Noise (rms)
V
O
=12 V; I
O
=0 A
V
O
=15 V; I
O
=0 A
V
O
=12 V; I
O
=0.8 A
V
O
=15 V; I
O
=0.6 A
-
-
-
-
25 mV
25 mV
25 mV
35 mV
50 mV
50 mV
50 mV
60 mV
Ripple and Noise (pk-pk)
V
O
=12V; I
O
=0A
V
O
=15V; I
O
=0A
V
O
=12V; I
O
=0.8A
V
O
=15V; I
O
=0.6A
-
-
-
-
85 mV
100 mV
60 mV
100 mV
120 mV
150 mV
100 mV
150 mV
Test conditions:
BW = 0-20 MHz; 1 uF Ceramic
capacitor and 33 uF Tantalum
capacitor at the output
Rise Time
-
5 mS
-
Overshoot at Turn on
-
0%
5%
Output Capacitance
33 uF
-
330 uF
The min output capacitance is
33 uF Tantalum capacitor at
the output
Transient Response
Overshoot
-
130 mV
200 mV
50% ~ 100%
Max Load
Settling Time
-
100 uS
200 uS
Overshoot
-
130 mV
200 mV
100% ~ 50%
Max Load
Settling Time
All
Outputs
- 100
uS
200 uS
di/dt = 0.1 A/uS; Vin = 3.3 V;
and with 33 uF Tantalum
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
3 V-3.6 V Input
12 V/0.8 A & 15 V/0.6 A Output
General Specifications
Parameter
Min
Typ
Max
Notes
Efficiency
V
O
=12 V
V
O
=15 V
82%
81%
86%
85%
-
-
Measured at Vin=3.3 V, full load
Switching Frequency
500 kHz
550 kHz
650 kHz
Output Trim Range
90% V
O
- 110%
V
O
MTBF
6,800,000 hours
Calculated Per Bell Core TR-332
(Vin=3.3 V; Vo=12 V; I
O
= 0.64 A;
T
a
= 25
C)
Dimensions (surface mount)
Inches (L W H)
Millimeters (L W H)
0.78 x 0.7 x 0.32
19.81 x 17.78 x 8.13
Dimensions (vertical)
Inches (L W H)
Millimeters (L W H)
0.7 x 0.308 x 0.65
17.78 x 7.82 x 16.51
Weight -
5.2
g
-
Note
: All specifications are typical at 25
C
unless otherwise stated.
Output Trim Equations
Equations for calculating the trim resistor (in k) given the desired adjusted voltage (Vadj) and the nominal
output voltage of the converter (Vnom) are shown below. The Trim Down resistor should be connected between
the Trim pin and Vout. The Trim Up resistor should be connected between the Trim pin and Ground. Only one of
the resistors should be used for any given application.
B
V
V
A
R
adj
nom
down
trim
-
-
=
-
D
V
V
C
R
nom
adj
up
trim
-
-
=
-
Vnom
A B C D
12 164.640
21.850
11.760 7.150
15.055 209.542 20.600 11.760 5.900
Vout
Trim
GND
Rtrim-down
Module
Vout
Trim
GND
Rtrim-up
Module
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
3 V-3.6 V Input
12 V/0.8 A & 15 V/0.6 A Output
Efficiency Data
E
f
f
i
ci
en
c
y
70.0%
72.0%
74.0%
76.0%
78.0%
80.0%
82.0%
84.0%
86.0%
88.0%
0.08
0.20
0.40
0.60
0.80
Output current (A)
3.0V
3.3V
3.6V
70.0%
72.0%
74.0%
76.0%
78.0%
80.0%
82.0%
84.0%
86.0%
88.0%
0.06
0.15
0.30
0.45
0.60
Output current (A)
E
f
f
i
ci
enc
y
3.0V
3.3V
3.6V
x7AH-01CX20
x7AH-01CX50
Thermal Derating Curves
x7AH-01CX20
x7AH-01CX50
2005 Bel Fuse Inc. Specifications subject to change without notice. 040805
CORPORATE FAR
EAST
EUROPE
Bel Fuse Inc.
Bel Fuse Ltd.
Bel Fuse Europe Ltd.
206 Van Vorst Street
8F/ 8 Luk Hop Street
Preston Technology Management Centre
Jersey City, NJ 07302
San Po Kong
Marsh Lane, Suite G7, Preston
Tel 201-432-0463
Kowloon, Hong Kong
Lancashire, PR1 8UD, U.K.
Fax 201-432-9542
Tel 852-2328-5515
Tel 44-1772-556601
www.belfuse.com
Fax 852-2352-3706
Fax 44-1772-888366
www.belfuse.com
www.belfuse.com
NON-ISOLATED DC/DC CONVERTERS
3 V-3.6 V Input
12 V/0.8 A & 15 V/0.6 A Output
S7AH-01C
V7AH-01C
Pin Connections
Pin
Function
1 Remote
On/Off
2 Vin
3 Ground
4 Vout
5 Trim
6 N/A
7 N/A
Pin Connections
Pin
Function
1 Remote
On/Off
2 Vin
3 Ground
4 Vout
5 Trim
b e l
b e l
b e l
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