- 1 -
demo board for SP6128A, a synchronous buck controller
Non-Isolated DC-DC SIP Modules:
3.0Vdc-5.5Vdc In, 0.9Vdc-3.3Vdc out, 10A
FEATURES:
DESCRIPTION:
The SP6128A demo board design is non-isolated dc-dc SIP module with a very high efficiency at
10A output. It has smallest size comparing with the current market products with the same power
range and low EMI. Standard features include remote ON/OFF with the customer selectable
positive and negative control, output voltage adjustment, soft start, over current and over
temperature protection. This demo board proves that SP6128A is a high performance, but yet
easy to use synchronous buck controller. It simplifies low voltage DC to DC power supply
designs without compromising performance.
High Efficiency: 94.5% at 3.3V output,10A
Small size and very low profile
43.2mm
7.25mm
13.97mm
(1.7in
0.285in
0.55in)
3V to 5.5V input voltage
All ceramic capacitors design
Negative or Positive remote On/Off
Thermal shut down protection
Low output ripple max 20mV
Output voltage adjustable with the trim function
Low EMI noise
Short circuit and over current protection
using Hiccup mode and auto-restart
Build in UVLO function
Wide operation temperature range
-40
C
to +85
C
0.1% line regulation &
0.3% load
regulation
-40
C
to +85
C
2
APPLICATION
workstations, servers
computer and its peripheral
distribution
power
architecture
telecommunications
equipment
data processing and storage equipment
LANs
and
WANs
high performance data processing IC
SCHEMATIC:
PCB Layout:
3
Top Layer
Internal-1 layer
Internal-2 layer
Bottom Layer
4
SST
SSB
CHARACTERISTIC CURVE (1.8V output)
Figure 1
Figure 2
Figure 3: input ripple @ Vin=3.3V, Io=10A
Figure 4: input ripple @ Vin=5V, Io=10A
SP6128A EVAL Board Eff
88
89
90
91
92
93
94
95
0
1
2
3
4
5
6
7
8
9
10
Load (A)
EFF (%)
3.3V
5V
SP6128A EVAL Board regulation
1.802
1.804
1.806
1.808
1.81
1.812
1.814
1.816
0
1
2
3
4
5
6
7
8
9
10
Load(A)
Output(V)
3.3V
5V
5
Figure 5:output ripple @ Vin=3.3V Io=10A
Figure 6:output ripple @ Vin=5V Io=10A
Figure 8 startup, Ch1:Vin, Ch2:Vout,
Ch3:Iin 2A/div @Io=10A
Figure 7: startup, Ch1:Vin, Ch2:Vout,
Ch3:Iin 2A/div @Io=10A
Figure 9: output short, Ch2: COM
Ch4:Iin 5A/div@Vin=3.0V
Figure 10: output short, Ch2: COM
Ch4:Iin 5A/div@Vin=5.0V
6
*
short circuit protection tested at with Cin=100uF, Tantalum
Figure11: transient response, Ch1:Vout
Ch2:Iout 2A/div load change
At 5A/us from 0.4A to 5A @
Vin=3.3V
Figure12: transient response, Ch1:Vout
Ch2:Iout 2A/div load change
At 5A/us from 0.4A to 5A @
Vin=5V
Figure13: short circuit Iin RMS value
Ch2: Vin, Ch4 Iin 2A/div
Figure14: short circuit Iin RMS value
Ch2: Vin, Ch4 Iin 2A/div
7
ELECTRICAL SPECIFICATIONS
Parameter Symbol
Min
Typ
Max
Units
Operating input voltage
Vin
2.9
6
Vdc
Input voltage ripple
Vinripple
250
300
mVp-p
Output voltage set point
accurate
1.5
%
Output regulation
Line regulation
Load regulation
0.1
0.3
%
%
Output ripple&noise
15
25
mVp-p
Output current
Io
10
A
Output current limit point
16
A
Over temperature protection
110
120
C
Negative remote control:
Logic low-module on
Logic high-module off
Vrem
Irem
Vrem
Irem
-0.7 0.3
100
2.4
0.5
V
A
V
mA
Positive remote control:
Logic high-module on
Logic low-module off
Vrem
Irem
Vrem
Irem
2.4
-0.7
1
0.8
1
V
mA
V
A
Turn-on time
5
ms
Short circuit input
current(RMS)
0.5 A
Output voltage trim range
-10
+10
% Vout ,nom
FEATURE DISCRIPTION
Output voltage trim function:
In this design,there is a trim pin that allows the customer to trim the output voltage to
10% off the
nominal voltage.
In the schematic on page 2, R3, R14, R2 and external trim resistor (Rtrim) comprise the trim function
circuit. To trim-up, connect Rtrim between trim pin and GND. The Rtrim value is equal to:
Rtrim=
14
2
8
.
0
R
V
R -
To trim-down, connect Rtrim between trim pin and Vout. The Rtrim value can be derived from:
Rtrim=
14
2
3
2
2
8
.
0
R
R
V
R
R
-
-
Remote On/OFF:
8
This design allows user to select positive or negative logic remote control. This demo board only
implements the negative logic remote control circuit. To change to positive logic, remove Q5, R7, R8,
and R12.and add D2 andD3.
Over temperature protection:
The over temperature protection will shut down the module when abnormal high temperature is detected
by the circuit.. The module will attempt to restart once the temperature cools down. The temperature set
point can be adjusted by resistor R11.
Mechanical Outline Diagram
Dimensions are in millimeter (inch)
IN FUNCTION
1 Vo
2 Vo
3 GND
4 GND
5 GND
6 ON/OFF
7 Trim
8 Vi
9 Vi
*the pin out is not the same as standard
BILL MATERIAL
43.2(1.7)
13.95(5.5)
1 2 3 4
5 6 7
8 9
7.25(0.285)
9
Item Quantity
Reference
Part
Manufacture
information
1 2
C1,C2
22u
TDK
C3225X5R1A226M
2 3
C3,C8,C13 1u
TDK
C2012X7R1C105K
3 3
C4,C5,C6 47u
TDK
C3225X5R0J476M
4 1
C9
470p
TDK
C1608C0G1H471J
5 1
C10
22p
TDK
C1608C0G1H220J
6 2
C11,C12 0.1u
TDK
C1608X7R1H104K
7 1
C14
6.8n
TDK
C1608X7R1H682K
8 1
D1
MBR0530 ON
semiconductor
10 1
D4
STPS2L25U ST
11 9
J1,J2,J3,J4,J5,J6,J7
,J8,J9
PIN
12 1
L1
SC5018-1R2M
Easy
Magnetic
13 2
Q1,Q2
IRF7811W IRF
14 1
R1
300
0603
15 1
R2
10.2k
0603
16 1
R3
8k
0603
17 1
R5
20k
0603
18 1
R6
4.22k
0603
19 1
R13
0
0603
20 1
R14
45k
0603
21 1
U1
SP6128A SIPEX
22 1
R11
100
0603
23 4
R7,R8,R10,R12
10K
0603
24 2
Q3,Q4
MMBT4401 ON
semiconductor
25 1
Q5
MMBT2907 ON
semiconductor
22 1
R9
NTC-100K TDK
NTCG204CH104J
For the low profile application, SC5015-1R2M from Easy magnetic recommended for L1
10
EFFICIENCY ON THE DIFFERENT OUTPUT VOLTAGE
Input voltage
Output voltage
Output current
Efficiency
Internal Trim resistor
3.0-5.5V 0.9V
10A
82%
80.6K
3.0-5.5V 1V
10A
84%
40.2K
3.0-5.5V 1.2V
10A
86%
20.5K
3.0-5.5V 1.5V
10A
88%
11.8K
3.0-5.5V 1.8V
10A
90.5%
8.06K
3.0-5.5V 2.0V
10A
90.5%
6.81K
3.0-5.5V 2.5V
10A
92.7%
4.75K
4.5-5.5V 3.3V
10A
94.5%
3.24K
SIGNAL PROCESSING EXCELLENCE
Headquarters and sales office
22 Linnell Circle
Billerica,MA 01821
TEL:978-667-8700
FAX:978-670-9001
E-mail:
sales@sipex.com
Sales office
233 South Hillview Drive
Milpitas,CA 95035
TEL:408-934-7500
FAX:408-935-7600
Application support
Jack Ni
TEL:978-671-4644
Email:
jni@sipex.com
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