16A Non-Isolated, SMT DC/DC Converter with wide trim

Technical Specification *
Non-Isolated
SMT Converter
9.6 - 14.4Vin 16A
16A Non-Isolated, SMT DC/DC Converter with wide trim
The NiQor™ SMT DC/DC converter is a non-isolated buck regulator, which employs synchronous rectification to achieve extremely high conversion effi-
Non-Isolated
ciency. The NiQor family of converters are used
predominately in DPA systems using a front end
DC/DC high power brick (48Vin to low voltage bus).
The non-isolated NiQor converters are then used at
the point of load to create the low voltage outputs
required by the design. The wide trim module can
be programmed to a variety of output voltages
through the use of a single external resistor.
Operational Features
• Ultra-high efficiency, up to 95% at full and half load
• Delivers 16 amps of output current with minimal derating - no heatsink required
• Input voltage range: 9.6 - 14.4V
• Programmable output voltages from 0.85 - 5.0V
• On-board input and output filter capacitor
• No minimum load requirement means no preload
resistors required
Protection Features
• Input under-voltage lockout disables converter at
low input voltage conditions
• Temperature compensated over-current shutdown
protects converter from excessive load current or
short circuits
• Output over-voltage protection protects load from
damaging voltages
• Thermal shutdown
Product # NQ12T50SMA16
Phone 1-888-567-9596
NQ12T50SMA16 wide trim module
Mechanical Features
• Industry standard SMT pin-out configuration
• Industry standard size: 1.3” x 0.53” x 0.29” (33 x
13.5 x 7.3 mm)
• Total weight: 0.18 oz. (5 grams), lower mass greatly
reduces vibration and shock problems
• Open frame construction maximizes air flow cooling
• Also available in SIP packaging
Control Features
• On/Off control
• Remote sense
• Output voltage trim (industry standard) permits custom voltages and voltage margining
• Fixed output voltage modules available (0.9 - 5.0V)
Safety Features
• UL 1950 recognized (US & Canada)
• TUV certified to EN60950
• Meets 72/23/EEC and 93/68/EEC directives
which facilitates CE Marking in user’s end product
• Board and plastic components meet UL94V-0 flammability requirements
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 1
Technical Specification
Non-Isolated
SMT Converter
MECHANICAL
DIAGRAM
9.6 - 14.4Vin 16A
Surface Mount Package
0.288+.018
1.30
(7.32+0.45)
(33.0)
see Note 4
0.025
(0.64)
1
2
3
4
0.075
(1.91)
0.063
0.405
(1.60)
(10.29)
Typ.
0.53
(13.5)
6
5
0.012+.007
0.297
(7.54)
0.048
0.487
0.100
Bottomside
Clearance
(1.6)
(1.22)
(12.37)
(2.54)
(0.3+0.17)
0.063
0.677
Typ.
(17.20)
Side View
0.867
(22.02)
1.177
(29.90)
Recommended SMT Pad Size:
Minimum: 0.074” x 0.122” (1.88mm x 3.1mm)
Maximum: 0.095” x 0.140” (2.41mm x 3.56mm)
Bottom View
NOTES
SMT CONTACT DESIGNATIONS
1) SMT Contacts: Material - Brass
Finish - Gold over Nickel plate
2) Undimensioned components are shown for visual
reference only.
3) All dimensions in inches (mm)
Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm)
x.xxx +/-0.010 in. (x.xx +/-0.25mm)
4) Coplanarity for pins 1-6 is 0.004” max
5) Weight: 0.18 oz. (5 g) typical
6) Vertical and horizontal SIP pin options also available.
7) Workmanship: Meets or exceeds IPC-A-610C Class II
Product # NQ12T50SMA16
Phone 1-888-567-9596
Pin No.
Name
Function
1
GND
Ground
2
Vout(+)
Positive output voltage
3
TRIM
Output Voltage Trim
4
SENSE(+)
Positive remote sense
5
Vin(+)
Positive input voltage
6
ON/OFF
Input to turn converter on/off
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 2
Technical Specification
Non-Isolated
SMT Converter
9.6 - 14.4Vin 16A
ELECTRICAL CHARACTERISTICS - NQ12T50SMA16 Series
TA=25°C, airflow rate=300 LFM, Vin=12Vdc unless otherwise noted; full operating temperature range is -40°C to +105°C ambient temperature with appropriate power derating. Specifications subject to change without notice.
Parameter
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Non-Operating
Operating
Operating Temperature
Storage Temperature
Voltage at ON/OFF input pin
INPUT CHARACTERISTICS
Operating Input Voltage Range
Input Under-Voltage Lockout
Turn-On Voltage Threshold
Turn-Off Voltage Threshold
Lockout Hysteresis
Maximum Input Current
No-Load Input Current
Disabled Input Current
Inrush Current Transient Rating
Response to Input Transient
Input Reflected-Ripple Current
Recommended Input Fuse
Input Filter Capacitor Value
Input Ripple Voltage
Product # NQ12T50SMA16
Module
Min.
All
All
All
All
All
0
-40
-55
-3
All
9.6
All
All
All
0.9V
1.2V
1.5V
1.8V
2.5V
3.3V
5.0V
0.9V
1.2V
1.5V
1.8V
2.5V
3.3V
5.0V
All
All
0.9-2.5V
3.3V
5.0V
0.9V
1.2V
1.5V
1.8V
2.5V
3.3V
5.0V
All
All
0.9V
1.2V
1.5V
1.8V
2.5V
3.3V
5.0V
8.25
7.25
Phone 1-888-567-9596
Typ.
Max.
Units
16
14.4
105
125
15
V
V
°C
°C
V
12
14.4
V
8.75
7.75
1.0
9.2
8.1
V
V
V
A
A
A
A
A
A
A
A
A
A
A
A
A
A
mA
A 2s
mV/V
mV/V
mV/V
mA
mA
mA
mA
mA
mA
mA
A
µF
mV
mV
mV
mV
mV
mV
mV
0.026
0.031
0.037
0.043
0.062
0.084
0.116
4
5
7.5
12.5
40
52
64
75
97
117
145
30
51
66
80
92
116
137
160
2.25
3.0
3.5
4.0
5.5
7.0
10.5
0.031
0.037
0.045
0.052
0.075
0.101
0.140
10
0.1
73
95
114
133
168
197
220
15
Notes & Conditions
continuous
continuous
9.6Vin, 100% Load, 10% trim up (all)
with min. output capacitance
80V/ms input transient (all)
pk-pk thru 1µH inductor; Fig 15-16 (all)
fast blow external fuse recommended
internal ceramic
RMS, full load, Figures 15, 17 (all)
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 3
Technical Specification
Non-Isolated
SMT Converter
9.6 - 14.4Vin 16A
ELECTRICAL CHARACTERISTICS (continued) - NQ12T50SMA16 Series
Parameter
OUTPUT CHARACTERISTICS
Output Voltage Set Point
Output Voltage Regulation
Over Line
Over Load
Over Temperature
Total Output Voltage Range
Output Voltage Ripple and Noise (pk-pk\RMS)
Operating Output Current Range
Output DC Over-Current Shutdown
Output Capacitance Range
DYNAMIC CHARACTERISTICS
Input Voltage Ripple Rejection
Module
Min.
Typ.
Max.
Units
0.9V
1.2V
1.5V
1.8V
2.5V
3.3V
5.0V
0.888
1.184
1.481
1.777
2.468
3.257
4.935
0.900
1.200
1.500
1.800
2.500
3.300
5.000
0.912
1.216
1.520
1.823
2.533
3.343
5.065
V
V
V
V
V
V
V
TBD
TBD
+0.50
3
mV
mV
%
V
V
V
V
V
V
V
mV
mV
mV
A
A
µF
All
All
All
0.9V
1.2V
1.5V
1.8V
2.5V
3.3V
5.0V
0.9-2.5V
3.3V
5.0V
All
All
All
25\10
30\10
35\10
0
17
100
22
90
65
0.9V
5.0V
Output Voltage during Load Current Transient
For a Step Change in Output Current (0.1A/µs)
All
For a Step Change in Output Current (3A/µs)
All
Settling Time
All
Turn-On Transient
Turn-On Time
0.9-1.5V
1.8-5.0V
Output Voltage Overshoot
All
EFFICIENCY
100% Load
0.9V
1.2V
1.5V
1.8V
2.5V
3.3V
5.0V
50% Load
0.9V
1.2V
1.5V
1.8V
2.5V
3.3V
5.0V
TEMP. LIMITS FOR POWER DERATING
Semiconductor Junction Temperature
All
Board Temperature
All
Product # NQ12T50SMA16
0.882
1.176
1.470
1.764
2.450
3.234
4.900
7
+1.50
0.918
1.224
1.530
1.836
2.550
3.366
5.100
40\12
50\17
60\20
16
27
5,000
0.75
1
Phone 1-888-567-9596
40
100
50
75
1.5
2
0
2.5
3
1
83
86
88
89
92
93
94
87
89
91
91
93
94
95
125
125
Notes & Conditions
12Vin; 50% load (all)
with sense pin
with sense pin, over sample, line, load,
temperature & life (all)
Full load;20MHz bandwidth; Figs 15, 18
Figure 23
>2.5 mW ESR
dB
dB
120 Hz; Figure 20
mV
mV
µs
50%-75%-50% Iout max, 100µF, Fig 13
50%-75%-50% Iout max, 470µF, Fig 14
ms
ms
%
to within 1.5% Vout nom., Figs 13-14
Figures 11-12
Full resistive load, Vout=100% nom. (all)
resistive load
%
%
%
%
%
%
%
%
%
%
%
%
%
%
Figures 1-4
°C
°C
Package rated to 150°C; Figs 5-10
UL rated max operating temp 130°C
Figures 1-4
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 4
Technical Specification
Non-Isolated
SMT Converter
9.6 - 14.4Vin 16A
ELECTRICAL CHARACTERISTICS (continued) - NQ12T50SMA16 Series
Parameter
Module
Min.
Typ.
Max.
Units
All
300
325
350
kHz
2.3
V
V
V
kW
%
%
%
%
°C
°C
FEATURE CHARACTERISTICS
Switching Frequency
ON/OFF Control
Off-State Voltage
On-State Voltage
Pull-Up Voltage
Pull-Up Resistance
Output Voltage Trim Range
Output Voltage Remote Sense Range
Output Over-Voltage Protection
All
All
All
All
All
All
0.9V
1.2-5.0V
Over-Temperature Shutdown
All
Over-Temperature Shutdown Restart Hysteresis
All
RELIABILITY CHARACTERISTICS
Calculated MTBF (Telcordia)
All
Calculated MTBF (MIL-217)
All
Field Demonstrated MTBF
All
2.65
Vin/2
10
-10
140
118
145
127
133
12
+10
+10
150
140
Notes & Conditions
may drop by 10% at light load
See Applications Information
Measured Vout+ to common pins; Table 1
Measured Vout+ to common pins
Over full temp range; % of nominal Vout
Average PCB Temperature
106 Hrs. TR-NWT-000332; 100% load, 200LFM, 40oC Ta
106 Hrs. MIL-HDBK-217F; 100% load, 200LFM, 40oC Ta
106 Hrs. See website for latest values
TBD
TBD
STANDARDS COMPLIANCE
Parameter P
Notes
STANDARDS COMPLIANCE
UL/cUL 60950
EN60950
72/23/EEC
93/68/EEC
Needle Flame Test (IEC 695-2-2)
IEC 61000-4-2
GR-1089-CORE
Telcordia (Bellcore) GR-513
File # E194341
Certified by TUV
test on entire assembly; board & plastic components UL94V-0 compliant
ESD test, 8kV - NP, 15kV air - NP (Normal Performance)
Section 7 - electrical safety, Section 9 - bonding/grounding
• An external input fuse must always be used to meet these safety requirements. Contact SynQor for official safety
certificates on new releases or download from the SynQor website.
QUALIFICATION TESTING
Parameter P
QUALIFICATION TESTING
Life Test
Vibration
Mechanical Shock
Temperature Cycling
Power/Thermal Cycling
Design Marginality
Humidity
Solderability
# Units
32
5
5
10
5
5
5
15 pins
Test Conditions
95% rated Vin and load, units at derating point, 1000 hours
10-55Hz sweep, 0.060” total excursion,1 min./sweep, 120 sweeps for 3 axis
100g minimum, 2 drops in x and y axis, 1 drop in z axis
-40°C to 100°C, unit temp. ramp 15°C/min., 500 cycles
Toperating = min to max, Vin = min to max, full load, 100 cycles
Tmin-10°C to Tmax+10°C, 5°C steps, Vin = min to max, 0-105% load
85°C, 85% RH, 1000 hours, continuous Vin applied except 5min./day
MIL-STD-883, method 2003
• Extensive characterization testing of all SynQor products and manufacturing processes is performed to ensure that we supply
robust, reliable product. Contact factory for official product family qualification document.
OPTIONS
PATENTS
SynQor provides various options for Packaging, Enable Logic,
and Feature Set for this family of DC/DC converters. Please consult the last page of this specification sheet for information on
available options.
SynQor is protected under various patents, see last page.
Product # NQ12T50SMA16
Phone 1-888-567-9596
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 5
Performance Curves
Non-Isolated
SMT Converter
95
95
90
90
Efficiency (%)
100
Efficiency (%)
100
85
80
5.0 Vo
3.3 Vo
2.5 Vo
1.8 Vo
1.5 Vo
1.2 Vo
0.9 Vo
75
70
65
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
85
5.0 Vo Min Line
5.0 Vo Max Line
1.8 Vo Min Line
1.8 Vo Max Line
1.2 Vo Min Line
1.2 Vo Max Line
80
75
70
65
15
16
0
1
2
3
Load Current (A)
93
3.5
92
3.0
Efficiency (%)
Power Dissipation (W)
94
4.0
2.5
2.0
5.0 Vo
3.3 Vo
2.5 Vo
1.8 Vo
1.5 Vo
1.2 Vo
0.9 Vo
1.5
1.0
0.5
0.0
2
3
4
5
6
7
8
9
10
5
6
7
8
9
10
11
12
13
14
15
16
Figure 2: Efficiency at min and max line vs. load current for 1.2Vo,
1.8Vo and 5.0Vo units at 25°C.
4.5
1
4
Load Current (A)
Figure 1: Efficiency at nominal output voltage vs. load current for nominal input voltage at 25°C.
0
9.6 - 14.4Vin 16A
11
12
13
14
15
91
90
89
88
25 C
55 C
87
85 C
86
16
0
100
200
300
400
500
Air Flow (LFM)
Load Current (A)
Figure 3: Power dissipation at nominal output voltage vs. load current
for nominal input voltage at 25°C.
Figure 4: Efficiency at 1.8Vout and 60% rated power vs. airflow rate
for ambient air temperatures of 25°C, 55°C, and 85°C (nominal input
voltage).
16
14
Iout (A)
12
10
8
6
Heavy CU board
Typ Install, 6-Layer, 2 oz. (71um) CU board
4
300 LFM (1.5 m/s) free air
2
100 LFM (0.5 m/s) free air
0
0
25
40
55
70
85
Ambient Air Temperature (oC)
Figure 5: Maximum output power derating curves for 0.9Vo, 1.2Vo,
1.5Vo units under various thermal conditions and nominal input voltage. See Thermal Considerations section for more details.
Product # NQ12T50SMA16
Phone 1-888-567-9596
Semiconductor junction temperature is
within 1°C of surface temperature
Figure 6: Thermal plot of 0.9Vo, 1.2Vo, 1.5Vo converters at nominal
Vin and 16 amp load current mounted on a 70°C, 6-Layer, 2 oz. copper
board (typical installation).
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 6
Performance Curves
Non-Isolated
SMT Converter
9.6 - 14.4Vin 16A
16
14
Iout (A)
12
10
8
6
Heavy CU board
Typ Install, 6-Layer, 2 oz. (71um) CU board
4
300 LFM (1.5 m/s) free air
2
100 LFM (0.5 m/s) free air
0
0
25
40
55
70
85
Ambient Air Temperature (oC)
Figure 7: Maximum output power derating curves for 1.8Vo, 2.5Vo
units under various thermal conditions and nominal input voltage. See
Thermal Considerations section for more details.
Semiconductor junction temperature is
within 1°C of surface temperature
Figure 8: Thermal plot of 1.8Vo, 2.5Vo converters at nominal Vin and
16 amp load current mounted on a 70°C, 6-Layer, 2 oz. copper board
(typical installation).
16
14
Iout (A)
12
10
8
6
Heavy CU board
Typ Install, 6-Layer, 2 oz. (71um) CU board
4
300 LFM (1.5 m/s) free air
2
100 LFM (0.5 m/s) free air
0
0
25
40
55
70
85
Ambient Air Temperature (oC)
Figure 9: Maximum output power derating curves for 3.3Vo, 5.0Vo
units under various thermal conditions and nominal input voltage. See
Thermal Considerations section for more details.
Figure 10: Thermal plot of 3.3Vo converter (16 amp load) and 5.0Vo
converter (14.6 amp load). Both at nominal Vin and mounted on a 70°C,
6-Layer, 2 oz. copper board (typical installation).
5.0Vout
5.0Vout
3.3Vout
3.3Vout
2.5Vout
2.5Vout
1.8Vout
1.5Vout
1.2Vout
0.9Vout
1.8Vout
1.5Vout
1.2Vout
0.9Vout
Figure 11: Turn-on transient at full load (resistive load) (400 µs/div).
Ch 1: ON/OFF input (5V/div)
Ch 2-8: Vout (1V/div)
Product # NQ12T50SMA16
Semiconductor junction temperature is
within 1°C of surface temperature
Phone 1-888-567-9596
Figure 12: Turn-on transient at zero load (400 µs/div).
Ch 1: ON/OFF input (5V/div)
Ch 2-8: Vout (1V/div)
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 7
Performance Curves
Non-Isolated
SMT Converter
9.6 - 14.4Vin 16A
5.0Vout
5.0Vout
1.8Vout
1.8Vout
0.9Vout
0.9Vout
100µ s/div
100µ s/div
Figure 13: Output voltage response for 0.9V, 1.8V, 5.0V units to step-change
in load current (50-75-50% of Iout max; di/dt=0.1A/µ s). Load cap: 100µ F,
100mW ESR tant, 10µ F cer. Ch 1: Iout (5A/div), Ch 2-4: Vout (100mV/div).
Figure 14: Output voltage response for 0.9V, 1.8V, 5.0V units to step-change
in load current (50-75-50% of Iout max; di/dt=3A/µ s). Load cap: 470µ F,
25mW ESR tant, 10µ F cer. Ch 1: Iout (5A/div), Ch 2-4: Vout (100mV/div).
See Fig. 16
1 µH
source
impedance
5.0Vout
See Fig. 17
See Fig. 18
iS
VSOURCE
VIN
C*
DC/DC
Converter
VOUT
10 µF
3.3Vout
2.5Vout
1.8Vout
1.5Vout
1.2Vout
100 µF
ceramic 100mW ESR
capacitor
tantalum
capacitor
* See values for recommended external input capacitance.
Inductor optional as needed.
Figure 15: Test set-up diagram showing measurement points for Input
Reflected Ripple Current (Figure 16), Input Terminal Ripple Voltage
(Figure 17), and Output Voltage Ripple (Figure 18).
0.9Vout
1 s/div
Figure 16: Input Reflected Ripple Current, is, through a 1 µ H source
inductor at nominal input voltage and rated load current (10 mA/div).
See Figure 15.
5.0Vout
5.0Vout
3.3Vout
3.3Vout
2.5Vout
2.5Vout
1.8Vout
1.8Vout
1.5Vout
1.5Vout
1.2Vout
1.2Vout
0.9Vout
1 s/div
Figure 17: Input Terminal Ripple Voltage at nominal input voltage and
rated load current (200 mV/div). Load capacitance: 10µ F ceramic cap
and 100µ F tantalum cap. Bandwidth: 20 MHz. See Figure 15.
Product # NQ12T50SMA16
1 s/div
0.9Vout
Phone 1-888-567-9596
Figure 18: Output Voltage Ripple at nominal input voltage and rated
load current (20 mV/div). Load capacitance: 10µ F ceramic cap and
100µ F tantalum cap.. Bandwidth: 20 MHz. See Figure 15.
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 8
Performance Curves
Non-Isolated
SMT Converter
0.1
9.6 - 14.4Vin 16A
0
0.9 V
0.01
1.2 V
1.5 V
1.8 V
2.5 V
0.001
3.3 V
5.0 V
Forward Transmission (dB)
Output Impedance ( )
-10
-20
-30
0.9 V
1.2 V
-40
1.5 V
1.8 V
-50
-60
2.5 V
-70
3.3 V
5.0 V
-80
-90
-100
0.0001
-110
10
100
1,000
10,000
100,000
100
1,000
Hz
10,000
100,000
Hz
Figure 19: Magnitude of incremental output impedance (Zout =
vout/iout) for nominal input voltage at full rated power with 100µ F tantalum output capacitor.
Figure 20: Magnitude of incremental forward transmission (FT =
vout/vin) for nominal input voltage at full rated power with 100µ F tantalum output capacitor.
100
10
10
0
0.9 V
1.2 V
-5
1.5 V
1.8 V
2.5 V
-10
3.3 V
5.0 V
-15
Input Impedance ( )
Reverse Transmission (dB)
5
0.9 V
1.2 V
1.5 V
1
1.8 V
2.5 V
3.3 V
0.1
5.0 V
-20
-25
0.01
10
100
1,000
10,000
100,000
10
Hz
100
1,000
10,000
100,000
Hz
Figure 21: Magnitude of incremental reverse transmission (RT =
iin/iout) for nominal input voltage at full rated power with 100µ F tantalum output capacitor.
Figure 22: Magnitude of incremental input impedance (Zin = vin/iin)
for nominal input voltage at full rated power with 100µ F tantalum output capacitor.
6.0
Vout nominal
Output Voltage (V)
5.0
4.0
3.0
Vout nom / 2
2.0
1.0
0.0
0
5
10
15
20
25
Load Current (A)
Figure 23: Output voltage vs. load current showing current limit inception point and fold-back current limit behavior.
Product # NQ12T50SMA16
Phone 1-888-567-9596
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 9
Technical Specification
Non-Isolated
SMT Converter
BASIC OPERATION AND FEATURES
The NiQor series non-isolated converter uses a buck-converter
that keeps the output voltage constant over variations in line,
load, and temperature. The NiQor modules employ synchronous rectification for very high efficiency.
Dissipation throughout the converter is so low that it does not
require a heatsink or metal baseplate for operation. The NiQor
converter can thus be built more simply and reliably using high
yield surface mount techniques on a single PCB substrate.
The NiQor series of SIPs and SMT converters uses the established industry standard footprint and pin-out configurations.
CONTROL FEATURES
REMOTE ON/OFF: The ON/OFF input permits the user to
control when the converter is on or off. There is currently a single option available for the ON/OFF input described in the
table below. Others may become available if demand exists.
Option
P Logic
Description
Positive/Open
Pin-Open
Float
Voltage
Vin / 2
Pin-Open
Converter
State
On
Pin Action
Pull Low = Off
OUTPUT VOLTAGE TRIM: The TRIM input permits the user to
adjust the output voltage according to the trim range specifications by using an external resistor. If the TRIM feature is not
being used, leave the TRIM pin disconnected.
TRIM-UP: To increase the output voltage from the nominal setpoint of 0.7525V using an external resistor, connect the resistor Rtrim-up between the TRIM and the Ground pin according to
the diagram below.
Vout
Sense+
Vin
On/Off
Gnd
Trim
Rtrim-up
For a desired increase of the nominal output voltage, the value
of the resistor should be:
Rtrim-up =
9.6 - 14.4Vin 16A
10500
VDES - 0.7525
_ 1000 (W)
or
VOUT = 0.7525 +
where
10500
Rtrim-up + 1000
(W)
VDES = Desired Output Voltage
To maintain the accuracy of the output voltage over load current, it is vital that any trim-up resistor be terminated directly to
the converter's ground foot, not at the connection to the load.
A separate Kelvin connection to the PCB pad for the ground
foot is optimal. Trim-down resistors should be terminated at the
converter's Sense+ pin.
We do not recommend bypassing the trim pin directly to
ground with a capacitor. The voltage gain from the trim pin to
output is rather large, 15:1. Ground bounce through a bypass
capacitor could introduce significant noise into the converter's
control circuit.
PROTECTION FEATURES
Input Under-Voltage Lockout: The converter is designed
to turn off when the input voltage is too low, helping avoid an
input system instability problem, described in more detail in the
application note titled “Input System Instability”. The lockout circuitry is a comparator with DC hysteresis. When the input voltage is rising, it must exceed the typical Turn-On Voltage
Threshold value (listed on the specification page) before the
converter will turn on. Once the converter is on, the input voltage must fall below the typical Turn-Off Voltage Threshold value
before the converter will turn off.
Output Current Limiting: The NQ12 family of converters
employs foldback current limiting. A typical output voltage-current curve is shown in Figure 23 in the Performance Curves section. Current limit is reached at about 125% of rated current.
Loads in excess of that limit will cause the output to droop. If
the load is sufficient to pull the output down to roughly 1/2 of
its nominal setpoint, foldback will ensue. From there, as the
load is further increased, the output current will decrease linearly to about 1/3 of rated current at zero Vout. Thus, operating into a dead short, the unit will deliver 1/3 rated current
indefinitely. This reduces stress on the converter and ensures
that prolonged short-circuits will not overheat the converter.
Since there is no "hiccup mode" to the current-limit operation,
Product # NQ12T50SMA16
Phone 1-888-567-9596
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 10
Technical Specification
Non-Isolated
SMT Converter
there is also no concern with operation or startup into large
capacitive loads. The voltage may rise slowly while charging
the output capacitance, but it will rise.
There are also no problems starting into a load that has a resistive V-I curve. As long as the load draws less than the current
limit value at 1/2 of the unit's setpoint voltage, proper startup
is ensured.
9.6 - 14.4Vin 16A
APPLICATION CONSIDERATIONS
Input Filtering/Capacitance/Damping: The filter circuit
of Figure C is often added to the converter's input to prevent
switching noise from reaching the input voltage bus.
Internal Over-Voltage Protection: To fully protect from
excessive output voltage, the NQ12 series contains two levels
of Output Over-Voltage Shutdown circuitry.
The first type monitors the output at the load via the Sense+ pin
(or the output if Sense+ is left open). If the sensed voltage
exceeds the (optionally trimmed) setpoint by ~10% this protective circuit asserts the converter's low-side switch until the output returns to normal. This circuit tracks the trimmed setpoint;
the +10% threshold is maintained over the wide trim range of
the T50 model. This circuit can also be benignly activated during the response to a large, fast drop in load current. In this
instance the converter's normal transient response is momentarily overridden by this OVP. The result is a slight asymmetry
in the converter's observed transient response.
It should be noted that there is no limit on this OVP; if a powerful external source attempts to raise the output of an NQ12
converter beyond 110% of its setpoint, the converter will sacrifice itself trying to draw down that external source and protect
its load from the overvoltage.
The second Output Over-Voltage Shutdown circuit independently compares the voltage at the converter's output pin with
that of a redundant reference. If the output ever exceeds
~125% of nominal setpoint, both converter switches are disabled. After the output voltage returns to normal, a softstart
cycle is initiated.
This OVP is independent of the trimmed setpoint. As such, the
converter's load is protected from faults in the external trim circuitry (such as a trim pin shorted to ground). Since the setpoint
of this OVP does not track trim, it is set at 125% of 5.0V, or
6.2V, in the wide-trim T50 model.
Over-Temperature Shutdown: A temperature sensor on
the converter senses the average temperature of the module.
The thermal shutdown circuit is designed to turn the converter
off when the temperature at the sensed location reaches the
Over-Temperature Shutdown value. It will allow the converter to
turn on again when the temperature of the sensed location falls
by the amount of the Over-Temperature Shutdown Restart
Hysteresis value.
Product # NQ12T50SMA16
Phone 1-888-567-9596
Figure C: NQ12 converter with Input Filter
In the SMA16 (surface mount) converters Cin = 30µF and in the
VMA16 (SIP) converters Cin = 45µF of high quality ceramic
capacitors. With Lin of 1µH, Cd should be 100-200µF and Rd
should be 0.1-0.2W, in most applications. For more information on designing the input filter and choosing proper values,
contact SynQor technical support.
With the values listed above, the ripple current in L1 will be
below 100mA RMS for all units. The full-load worst-case filter
operation is summarized in Table 1.
Vout
Model
0.9
1.0
1.2
1.5
1.8
2.0
2.5
3.3
5.0
Current
(A RMS)
5.2
5.5
6.0
6.7
7.4
7.8
8.8
10.4
12.3
Ripple
(V RMS)
0.06
0.07
0.08
0.09
0.11
0.11
0.13
0.15
0.16
Current in L1
(mA RMS)
32
34
40
47
54
59
69
81
86
Vp Ripple
(V RMS)
0.04
0.04
0.05
0.06
0.07
0.08
0.09
0.10
0.11
Current in L1
(mA RMS)
21
22
27
31
36
39
46
54
57
Table 1: Full Load Input Filter Performance, SMA16
Adding significant external pure ceramic capacitance directly
across the converter's input pins is not recommended. Parasitic
inductance associated with the input pin geometry and PCB
traces can create a high-Q CLC circuit with any external capacitors. Just a few nano-Henries of parasitic inductance can create a resonance (or an overtone) near the converter's switching
frequency. Cin has a reactance of 10-20mW at the 330kHz
switching frequency. To avoid this high-frequency resonance,
any external input filter should exhibit a net source impedance
of at least 20mW resistive through this frequency range. This
requirement is easily met with the damping elements discussed
above. Adding a small amount (a few µF) of high-frequency
external ceramic will not violate it.
If using converters at higher powers, do consider the ripple current rating of Cd. Contact SynQor technical support for more
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 11
Technical Specification
Non-Isolated
SMT Converter
9.6 - 14.4Vin 16A
information.
Output Capacitance: It is recommended to add at least
100µF of capacitance, with an ESR in the 0.1W range, to the
output of the SMA16 series of converters. The VMA16 series
has this capacitance included internally. In many applications,
however, additional external output capacitance is required to
reduce the response to load transients to an allowable level.
The output impedance of these converters can be quite accurately modeled from DC to about 100kHz as shown in Figure
D. A further simplified version of it, valid below 40Hz and
above 1kHz, is shown
in Figure E. In the
SMA16 case, the models depict the minimum
recommended output
capacitance, Ct with its
resistance Rt. In the
VMA16 family, that
capacitor is again
included in the converter.
Figure D: NQ12 Passive Output Model
If the dynamic characteristics of the load
are known, any standard simulator can
use these models to
predict the in-circuit
transient response.
If the transients are
Figure E: Simplified NQ12 Output Model current steps then
Table 3 provides
values for ESRd and Cd for different allowable responses. The
allowable step response is normalized to a 1A step, and the
maximum allowable value of ESRd can be read from the table.
Figure F: Converter with Additional Output Capacitance
For minimal overshoot upon recovery, Cd should be related to
the minimum in-circuit net ESR.
Cd >
parallel (L1, L2)
ESRdmin2
The third column in Table 3 gives Cdmin for a 40% reduction
in ESR and the highest L1||L2 value in Table 2. For more
detailed derivations of these values, contact SynQor technical
support.
Load Current
Step Response
Pk mV/Amp
23
19
14
9
5
External Capacitor
ESRd max
0.1*
0.05
0.025
0.0125
0.00625
Cd min (uF)
100*
400
1,600
6,400
25,600
* Included in VMA, min recommended for SMA
Table 3: External Capacitor Values for Different Step Responses
Thermal Performance (SMA16): While it's impossible to
be exact, a simplified thermal model for the mounted converter
is detailed below.
Figure G: Thermal Model for NQ12 Surface Mount
Table 2: Component Values for Passive Output Models
Product # NQ12T50SMA16
Phone 1-888-567-9596
• Rt_J-Pcb models the conduction of heat from the converter's
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 12
Technical Specification
Non-Isolated
SMT Converter
pads. Solder mask should be used to eliminate solder wicking
into the vias.
hottest junction to the converter's PCB at large. It is about
3oC/W for converters running at higher output voltage, and
about 4oC/W for lower voltage converters.
Pick and Place: The NiQor surface mount modules are
designed for automated assembly using standard SMT pick and
place equipment. The modules have a centrally located inductor component with a flat surface area to be used for component pick-up. The units use open frame construction and have a
low mass that is within the capability of standard pick and
place equipment. Those modules however have a larger mass
than most conventional SMT components and so variables such
as nozzle size, tip style, handling speed, and placement pressure should be optimized for best results. A conformal tipped
placement nozzle design is recommended. Coplanarity of better than 0.004" (0.1mm) is achieved through the SMT NiQor's
terminal design.
• Rt_Pcb-Amb models the power dissipation from converter
PCB to the air stream. It ranges from about 15oC/W at
400LFM to about 25oC/W 100LFM.
• Rt_Pcb-Feet expresses the thermal path from the converter's
PCB though its mounting feet; it is about 3oC/W.
• Rt_spread models the heat spreading on the PCB to which the
converter is mounted and is largely dependent upon the construction and layout of that PCB.
• T_mount is the temperature of that PCB in the greater vicinity
of the converter.
As is evident, the values for Rt_spread and T_mount will have
great effect upon the thermal operation of the converter. With
Rt_Pcb-Amb being 5 to 8 times as large as Rt_Pcb-Feet, in most
applications these converters will be predominantly cooled via
thermal conduction through their feet. Airflow and T_Amb will
have only a minimal cooling effect.
Reflow Soldering Guidelines: Figure H shows a typical
reflow profile for a eutectic solder process. Due to variations
in customer applications, materials and processes, it is not feasible for SynQor to recommend a specific reflow profile. The
customer should use this profile as a guideline only. Since the
NiQor surface mount modules have a larger thermal mass and
lower thermal resistance than standard SMT components, it
may be necessary to optimize the solder reflow profile based
on limitations of the other components on the customer board.
Sufficient reflow time must be allowed to fuse the plating on the
connection to ensure a reliable solder joint. The solder reflow
profile should be confirmed by accurately measuring the SMT
interconnect leads. The guidelines illustrated in figure H must be
observed to ensure the maximum case temperature of 260°C
(exposure for 5 seconds or less) is not exceeded for the NiQor
units.
• Rt_spread should be minimized. Attach the converter to
large copper planes, on multiple layers, with multiple vias
near the mounting feet.
• T_mount should also be minimized. Place the converter far
enough away from other sources of heat on the PCB so that
it is as cool as practical.
• If operation near derating limits is even suspected, thermal
performance should be verified with the unit mounted in its
intended manner and powered in circuit with all neighboring
circuitry active. Attach a thermocouple to the converter's
hotspot as shown in Figures 6, 8, and 10 in the Performance
Curves section.
SURFACE MOUNT INFORMATION
PCB Layout Considerations: SynQor
recommends that the customer use a non-solder mask defined pad design. The minimum
recommended pad size is 0.074" x 0.122"
(1.88mm x 3.1mm) and the maximum pad
size is 0.095" x 0.140" (2.41mm x
3.56mm), see mechanical diagram on page
2. Interconnection to internal power planes
is typically required. This can be accomplished by placing a number of vias between
the SMT pad and the relevant plane. The
number and location of the vias should be
determined based on electrical resistance,
current and thermal requirements. "Via-inpad" design should be avoided in the SMT
Product # NQ12T50SMA16
9.6 - 14.4Vin 16A
Maximum Temperature (+210-260oC)
Eutectic Solder Melting Point (+183oC)
(+150-155oC)
Pre-heat
•
Reflow
Soak
< 2.5 C/sec
o
•
0.5-0.6oC/sec
•
60 to 90 sec.,
typ., 2 min max
•
1.3-1.6oC/sec
•
30 to 60 sec., typ.,
90 sec max
Cool Down
2 to 4 min.
Figure H: Typical Eutectic (96.5Sn/3.0Ag/0.5Cu) Solder Profile
Phone 1-888-567-9596
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 13
Technical Specification
Non-Isolated
SMT Converter
9.6 - 14.4Vin 16A
Moisture Sensitivity: The NiQor surface mount modules
have an MSL rating 1 per IPC/JEDEC J-STD-033A.
Cleaning and Drying: When possible, a no-clean solder
paste system should be used to solder the NiQor SMT units to
their application board. The modules are suitable for aqueous
washing, however, the user must ensure sufficient drying to
remove all water from the converter before powering up.
Inadequate cleaning and drying can affect the reliability of the
converter and the testing of the final assembly.
Product # NQ12T50SMA16
Phone 1-888-567-9596
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 14
Technical Specification
Non-Isolated
SMT Converter
9.6 - 14.4Vin 16A
PART NUMBERING SYSTEM
ORDERING INFORMATION
The part numbering system for SynQor’s NiQor DC/DC converters follows the format shown in the example below.
The tables below show the valid model numbers and ordering options for converters in this product family. When
ordering SynQor converters, please ensure that you use the
complete 15 character part number consisting of the 12
character base part number and the additional 3 characters
for options.
NQ 12 T50 S M A 16 P S S
Options (see
Ordering Information)
Output Current
Thermal Design
Performance Level
Packaging
Output Voltage
Input Voltage
Product Family
The first 12 characters comprise the base part number and
the last 3 characters indicate available options.
Model Number
Input Voltage
NQ12009SMA16xyz
NQ12010SMA16xyz
NQ12012SMA16xyz
NQ12015SMA16xyz
NQ12018SMA16xyz
NQ12020SMA16xyz
NQ12025SMA16xyz
NQ12033SMA16xyz
NQ12050SMA16xyz
NQ12T50SMA16xyz *
9.6 - 14.4 V
9.6 - 14.4 V
9.6 - 14.4 V
9.6 - 14.4 V
9.6 - 14.4 V
9.6 - 14.4 V
9.6 - 14.4 V
9.6 - 14.4 V
9.6 - 14.4 V
9.6 - 14.4 V
Output Max Output
Voltage
Current
0.9 V
16 A
1.0 V
16 A
1.2 V
16 A
1.5 V
16 A
1.8 V
16 A
2.0 V
16 A
2.5 V
16 A
3.3 V
16 A
5.0 V
16 A
0.9-5.0 V
16 A
* Represents the wide trim unit. Detailed specifications for fixed
Application Notes
output voltage modules are located in a separate datasheet locat-
A variety of application notes and technical white papers
can be downloaded in pdf format at www.synqor.com.
ed on the SynQor website.
The following option choices must be included in place of
the x y z spaces in the model numbers listed above.
Options Description: x y z
PATENTS
SynQor holds the following U.S. patents, one or more of which apply
to each product listed in this document. Additional patent applications
may be pending or filed in the future.
5,999,417
6,222,742
6,545,890
6,577,109
6,594,159
6,731,520
6,894,468
6,896,526
6,927,987
7,050,309
7,072,190
7,085,146
7,119,524
7,269,034
7,272,021
7,272,023
7,558,083
7,564,702
Contact SynQor for further information:
Phone:
Toll Free:
Fax:
E-mail:
Web:
Address:
Product # NQ12T50SMA16
978-849-0600
888-567-9596
978-849-0602
[email protected]nqor.com
www.synqor.com
155 Swanson Road
Boxborough, MA 01719
Phone 1-888-567-9596
Enable Logic
Pin Style
Feature Set
P - Positive/Open
S - SMT
S - Standard
Warranty
SynQor offers a three (3) year limited warranty. Complete warranty
information is listed on our web site or is available upon request from
SynQor.
Information furnished by SynQor is believed to be accurate and reliable.
However, no responsibility is assumed by SynQor for its use, nor for any
infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any
patent or patent rights of SynQor.
Doc.# 005-2NS12TE Rev. B
03/23/10
Page 15