LSN-1/10-D12 - Datel, Inc.

+INPUT

(7,8)

COMMON

(6)

PWM

CONTROLLER

CURRENT

SENSE

REFERENCE &

ERROR AMP

ON/OFF

CONTROL

(11)

OUT

TRIM

(10)

+OUTPUT

(1,2,4)

330µF100µF

66µF

10.5Ω

+SENSE

(3)

COMMON

(5)

➀

Single Output

LSN-10A D12 Models

Features

Non-Isolated, 12VIN, 1-5VOUT

10 Amp DC/DC’s in SIP Packages

Figure 1. Simpliﬁ ed Schematic

LSN Series D12 SIP's (single-in-line packages) are ideal building blocks for

emerging, on-board power-distribution schemes in which isolated 12V buses deliver

power to any number of non-isolated, step-down buck regulators. LSN D12 DC/DC's

accept a 12V input (10.8V to 13.2V input range) and convert it, with the highest

efﬁ ciency in the smallest space, to a 1, 1.1, 1.2, 1.3, 1.5, 1.8, 2, 2.5, 3.3 or 5 Volt

output fully rated at 10 Amps.

LSN D12's are ideal point-of-use/load power processors. They typically require

no external components. Their vertical-mount packages occupy a mere 0.7 square

inches (4.5 sq. cm), and reversed pin vertical mount allows mounting to meet

competitor's keep out area. Horizontal-mount packages ("H" sufﬁ x) are only 0.34

inches (8.6mm) high.

The LSN's best-in-class power density is achieved with a fully synchronous,

ﬁ xed-frequency, buck topology that also delivers: high efﬁ ciency (96% for 5VOUT

models), low noise (30 to 50mVp-p typ.), tight line/load regulation (±0.1%/±0.25%

max.), quick step response (100µsec), stable no-load operation, and no output

reverse conduction.

The fully functional LSN’s feature output overcurrent detection, continuous

short-circuit protection, an output-voltage trim function, a remote on/off control pin

(pull high to disable), thermal shutdown and a sense pin. High efﬁ ciency enables

the LSN D12's to deliver rated output currents of 10 Amps at ambient temperatures

to +68°C with 100 lfm air ﬂ ow.

If your new system boards call for three or more supply voltages, check out the

economics of on-board 12V distributed power. If you don't need to pay for multiple

isolation barriers, DATEL's non-isolated LSN D12 SIP's will save you money.

INNOVATION and EX C ELL E N C

■

Step-down buck regulators for new

distributed 12V power architectures

12V input (10.8-13.2V range)

1/1.1/1.2/1.3/1.5/1.8/2/2.5/3.3/5VOUT @10A

Non-isolated, ﬁ xed-frequency,

synchronous-rectiﬁ er topology

Outstanding performance:

• ±1.25% setpoint accuracy

• Efﬁ ciencies to 96% @ 10 Amps

• Noise as low as 30mVp-p

• Stable no-load operation

• Trimmable output voltage

Remote on/off control

Sense pin on standard models

Thermal shutdown

No derating to +68°C with 100 lfm

UL/IEC/EN60950 certiﬁ ed

EMC compliant

DATEL, Inc., Mansﬁ eld, MA 02048 (USA) · Tel: (508)339-3000, (800)233-2765 Fax: (508)339-6356 · Email: sales@datel.com · Internet: www.datel.com

➀ For devices with the sense-pin removed ("B" sufﬁ x),

the feedback path is through the +Output pin and not

the +Sense pin.

LSN-10A D12 Series NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

LSN-1/10-D12 1 10 45 65 ±0.1% ±0.25% 12 10.8-13.2 39/1.02 83% 86% 86% B5/B5x, P59

LSN-1.1/10-D12 1.1 10 45 60 ±0.1% ±0.25% 12 10.8-13.2 45/1.1 85% 88% 87.5% B5/B5x, P59

LSN-1.2/10-D12 1.2 10 45 60 ±0.1% ±0.25% 12 10.8-13.2 45/1.19 85% 88% 87.5% B5/B5x, P59

LSN-1.3/10-D12 1.3 10 45 60 ±0.1% ±0.25% 12 10.8-13.2 45/1.3 85% 88% 87.5% B5/B5x, P59

LSN-1.5/10-D12 1.5 10 30 45 ±0.1% ±0.25% 12 10.8-13.2 54/1.47 86% 89% 88% B5/B5x, P59

LSN-1.8/10-D12 1.8 10 30 45 ±0.1% ±0.25% 12 10.8-13.2 53/1.75 87% 90.5% 89.5% B5/B5x, P59

LSN-2/10-D12 2 10 30 45 ±0.1% ±0.25% 12 10.8-13.2 59/1.9 88.5% 91% 90% B5/B5x, P59

LSN-2.5/10-D12 2.5 10 35 50 ±0.1% ±0.25% 12 10.8-13.2 60/2.3 90.5% 92.5% 92% B5/B5x, P59

LSN-3.3/10-D12 3.3 10 40 55 ±0.1% ±0.25% 12 10.8-13.2 69/3 92.5% 94% 93.5% B5/B5x, P59

LSN-5/10-D12 5 10 50 75 ±0.1% ±0.25% 12 10.8-13.2 75/4.5 94% 96% 95.5% B5/B5x, P59

12345 76891011

2.00

(50.80)

0.030 ±0.001 DIA.

(0.762 ±0.025)

0.55

(13.97)

0.34

(8.64)

0.20

(5.08)

0.110

(2.79)

0.046

(1.17)

0.05

(1.27)

0.400

(10.16)

4 EQ. SP. @

0.100 (2.54)

0.500

(12.70)

5 EQ. SP. @

0.100 (2.54)

1.000

(25.40)

0.17

(4.32)

LAYOUT PATTERN

TOP VIEW

0.34

(8.64)

0.25

(6.35)

➀ Typical at TA = +25°C under nominal line voltage and full-load conditions, unless otherwise

noted. All models are tested and speciﬁ ed with external 22µF tantalum input and output

capacitors. These capacitors are necessary to accommodate our test equipment and may

not be required to achieve speciﬁ ed performance in your applications. See I/O Filtering and

Noise Reduction.

MECHANICAL SPECIFICATIONS

Case B5

Vertical Mounting

(Standard)

➁ Ripple/Noise (R/N) is tested/speciﬁ ed over a 20MHz bandwidth and may be

reduced with external ﬁ ltering. See I/O Filtering and Noise Reduction for details.

➂ These devices have no minimum-load requirements and will regulate under no-load conditions.

Regulation speciﬁ cations describe the output-voltage deviation as the line voltage or load is

varied from its nominal/midpoint value to either extreme.

➃ Nominal line voltage, no-load/full-load conditions.

PART NUMBER STRUCTURE

* Pin 3 (+Sense) removed

for "B" sufﬁ x models.

0.35

(8.89)

0.21

(5.33)

0.16

(4.06

)

0.360

(9.14)

12345 7689

ISOLATING

PA D

10 11

2.00

(50.80)

0.030 ±0.001 DIA.

(0.762 ±0.025)

0.55

(13.97)

0.05

(1.27)

0.05

(1.27)

0.55

(13.97)

0.50

(12.7)

0.400

(10.16)

0.56

(14.22)

0.53

(13.46)

4 EQ. SP. @

0.100 (2.54)

0.500

(12.70)

5 EQ. SP. @

0.100 (2.54)

1.000

(25.40)

LAYOUT PATTERN

TOP VIEW

RECOMMENDED

COPPER PAD

ON PCB (0.55 SQ. IN.)

Case B5A

Horizontal Mounting

Performance Speciﬁ cations and Ordering Guide ➀

Package

VOUT IOUT VIN Nom. Range IIN ➃ (Case,

Model (Volts) (Amps) Typ. Max. Line Load (Volts) (Volts) (mA/A) Min. Typ. Typ. Pinout)

Output Input

R/N (mVp-p) ➁ Regulation (Max.) ➂

Efﬁ ciency

Full Load ½ Load

LAYOUT PATTERN

TOP VIEW

0.36

(9.14)

0.20

(5.08)

0.106

(2.69)

0.046

(1.17)

0.36

(9.14)

0.306

(7.8)

12345 76891011

2.00

(50.80)

0.030 ±0.001 DIA.

(0.762 ±0.025)

0.55

(13.97)

0.05

(1.27)

0.400

(10.16)

4 EQ. SP. @

0.100 (2.54)

0.500

(12.70)

5 EQ. SP. @

0.100 (2.54)

1.000

(25.40)

0.17

(4.32)

Case B5B

Reverse Pin

Vertical Mounting

(Tyco-compatible)

See page 12 for Part Number

Structure and ordering details.

Pin Function P59* Pin Function P59* Pin Function P59*

1 +Output 5 Common 9 No Pin

2 +Output 6 Common 10 VOUT Tr i m

3 +Sense * 7 +Input 11 On/Off Control

4 +Output 8 +Input

I/O Connections

Maximum Rated Output

Current in Amps

Non-Isolated SIP

Output

Conﬁ guration:

L = Unipolar

Low Voltage

Nominal Output Voltage:

1, 1.1, 1.2, 1.3, 1.5, 1.8, 2, 2.5, 3.3

or 5 Volts

Input Voltage Range:

D12 = 10.8 to 13.2 Volts

(12V nominal)

L SN 10-/D12 B

1.8

B Sufﬁ x:

No Remote Sense

(Pin 3 removed)

H Sufﬁ x:

Horizontal Mount

J Sufﬁ x:

Reversed Pin

Vertical Mount

LSN-10A D12 Models

NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

Input

Input Voltage Range 10.8-13.2 Volts (12V nominal)

Input Current:

Normal Operating Conditions See Ordering Guide

Inrush Transient 0.08A2sec

Standby/Off Mode 8mA

Output Short-Circuit Condition ➁ 40mA average

Input Reﬂ ected Ripple Current ➁ 100mAp-p

Input Filter Type Capacitive (66µF)

Overvoltage Protection None

Reverse-Polarity Protection None

Undervoltage Shutdown None

On/Off Control ➁ ➂ On = open (internal pull-down)

Off = +2.8V to +VIN (<3mA)

Output

VOUT Accuracy (50% load) ±1.25% maximum

Minimum Loading ➀ No load

Maximum Capacitive Load 2000µF (low ESR, OSCON)

VOUT Trim Range ➁ ±10%

Ripple/Noise (20MHz BW) ➀ ➁ ➃ See Ordering Guide

Total Accuracy 3% over line/load temperature

Efﬁ ciency ➁ See Ordering Guide

Overcurrent Detection and Short-Circuit Protection: ➁

Current-Limiting Detection Point 17 (13-23.5) Amps

Short-Circuit Detection Point 98% of VOUT set

SC Protection Technique Hiccup with auto recovery

Short-Circuit Current 400mA average

Dynamic Characteristics

Transient Response (50% load step) 100µsec to ±2% of ﬁ nal value

Start-Up Time: ➁

VIN to VOUT and On/Off to VOUT 70msec for VOUT = 1V

16msec for VOUT = 1.1V to 5V

Switching Frequency:

1V/1.1V, 1.2V, 1.3 Models 105/125kHz ±10%

1.5V/1.8V, 2V Models 160/177kHz ±10%

2.5V, 3.3V, 5V Models 200kHz ±7.5%

Environmental

Calculated MTBF ➄ 2.3 -1.8 million hours (1VOUT to 5VOUT)

Operating Temperature: (Ambient) ➁

Without Derating (Natural convection) –40 to +48/64°C (model dependent)

With Derating See Derating Curves

Thermal Shutdown +115°C

Physical

Dimensions See Mechanical Speciﬁ cations

Pin Dimensions/Material 0.03" (0.76mm) round copper with

tin-lead plate over nickel underplate

Weight 0.3 ounces (8.5g)

Flamability Rating UL94V-0

Performance/Functional Speciﬁ cations

Typical @ TA = +25°C under nominal line voltage and full-load conditions unless noted. ➀

➀ All models are tested and speciﬁ ed with external 22µF tantalum input and output capacitors.

These capacitors are necessary to accommodate our test equipment and may not be

required to achieve speciﬁ ed performance in your applications. All models are stable and

regulate within spec under no-load conditions.

➁ See Technical Notes and Performance Curves for details.

➂ The On/Off Control (pin 11) is designed to be driven with open-collector logic or the appli-

cation of appropriate voltages (referenced to Common, pins 5 and 6).

➃ Output noise may be further reduced with the installation of additional external output

ﬁ ltering. See I/O Filtering and Noise Reduction.

➄ MTBF’s are calculated using Telcordia SR-332(Bellcore), ground ﬁ xed, TA = +25°C, full

power, natural convection, +67°C pcb temperature.

TECHNICAL NOTES

Input Voltage:

Continuous or transient 15 Volts

On/Off Control (Pin 11) +VIN

Input Reverse-Polarity Protection None

Output Overvoltage Protection None

Output Current Current limited. Devices can

withstand sustained output short

circuits without damage.

Storage Temperature –40 to +125°C

Lead Temperature (soldering, 10 sec.) +300°C

These are stress ratings. Exposure of devices to any of these conditions may adversely

affect long-term reliability. Proper operation under conditions other than those listed in the

Performance/Functional Speciﬁ cations Table is not implied.

Absolute Maximum Ratings

Return Current Paths

The LSN D12 SIP’s are non-isolated DC/DC converters. Their two Common

pins (pins 5 and 6) are connected to each other internally (see Figure 1). To

the extent possible (with the intent of minimizing ground loops), input return

current should be directed through pin 6 (also referred to as –Input or

Input Return), and output return current should be directed through pin 5

(also referred to as –Output or Output Return). Any on/off control signals

applied to pin 11 (On/Off Control) should be referenced to Common

(speciﬁ cally pin 6).

I/O Filtering and Noise Reduction

All models in the LSN D12 Series are tested and speciﬁ ed with external

22µF tantalum input and output capacitors. These capacitors are necessary

to accommodate our test equipment and may not be required to achieve?

desired performance in your application. The LSN D12's are designed with

high-quality, high-performance internal I/O caps, and will operate within spec

in most applications with no additional external components.

In particular, the LSN D12's input capacitors are speciﬁ ed for low ESR

and are fully rated to handle the units' input ripple currents. Similarly, the

internal output capacitors are speciﬁ ed for low ESR and full-range frequency

response. As shown in the Performance Curves, removal of the external 22µF

tantalum output caps has minimal effect on output noise.

In critical applications, input/output ripple/noise may be further reduced using

ﬁ ltering techniques, the simplest being the installation of external I/O caps.

External input capacitors serve primarily as energy-storage devices. They

minimize high-frequency variations in input voltage (usually caused by IR

drops in conductors leading to the DC/DC) as the switching converter draws

pulses of current. Input capacitors should be selected for bulk capacitance (at

appropriate frequencies), low ESR, and high rms-ripple-current ratings. The

switching nature of modern DC/DC's requires that the dc input voltage

source have low ac impedance at the frequencies of interest. Highly inductive

source impedances can greatly affect system stability. Your speciﬁ c system

conﬁ guration may necessitate additional considerations.

Output ripple/noise (also referred to as periodic and random deviations

or PARD) may be reduced below speciﬁ ed limits with the installation of

additional external output capacitors. Output capacitors function as true ﬁ lter

LSN-10A D12 Series NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

elements and should be selected for bulk capacitance, low ESR, and appro-

priate frequency response. Any scope measurements of PARD should be

made directly at the DC/DC output pins with scope probe ground less than

0.5" in length.

All external capacitors should have appropriate voltage ratings and be located

as close to the converters as possible. Temperature variations for all relevant

parameters should be taken into consideration.

The most effective combination of external I/O capacitors will be a function

of your line voltage and source impedance, as well as your particular load and

layout conditions. Our Applications Engineers can recommend potential solu-

tions and discuss the possibility of our modifying a given device’s internal ﬁ lter-

ing to meet your speciﬁ c requirements. Contact our Applications Engineering

Group for additional details.

Input Fusing

Most applications and or safety agencies require the installation of fuses

at the inputs of power conversion components. LSN D12 Series DC/DC

converters are not internally fused. Therefore, if input fusing is mandatory,

either a normal-blow or a slow-blow fuse with a value no greater than 9 Amps

should be installed within the ungrounded input path to the converter.

As a rule of thumb however, we recommend to use a normal-blow or slow-

blow fuse with a typical value of about twice the maximum input current,

calculated at low line with the converters minimum efﬁ ciency.

Safety Considerations

LSN D12 SIP's are non-isolated DC/DC converters. In general, all DC/DC's

must be installed, including considerations for I/O voltages and spacing/

separation requirements, in compliance with relevant safety-agency speci-

ﬁ cations (usually UL/IEC/EN60950).

In particular, for a non-isolated converter's output voltage to meet SELV

(safety extra low voltage) requirements, its input must be SELV compliant.

If the output needs to be ELV (extra low voltage), the input must be ELV.

Input Overvoltage and Reverse-Polarity Protection

LSN D12 SIP Series DC/DC's do not incorporate either input overvoltage

or input reverse-polarity protection. Input voltages in excess of the speciﬁ ed

absolute maximum ratings and input polarity reversals of longer than "instan-

taneous" duration can cause permanent damage to these devices.

Start-Up Time

The VIN to VOUT Start-Up Time is the interval between the time at which a

ramping input voltage crosses the lower limit of the speciﬁ ed input voltage

range (10.8 Volts) and the fully loaded output voltage enters and remains

within its speciﬁ ed accuracy band. Actual measured times will vary with input

source impedance, external input capacitance, and the slew rate and ﬁ nal

value of the input voltage as it appears to the converter.

The On/Off to VOUT Start-Up Time assumes the converter is turned off via the

On/Off Control with the nominal input voltage already applied to the converter.

The speciﬁ cation deﬁ nes the interval between the time at which the converter

is turned on and the fully loaded output voltage enters and remains within its

speciﬁ ed accuracy band. See Typical Performance Curves.

On/Off Control and Power-up Sequencing

The On/Off Control pin may be used for remote on/off operation. LSN D12 SIP

Series DC/DC's are designed so they are enabled when the control pin is

left open (internal pull-down to Common) and disabled when the control pin is

pulled high (+2.8V to +VIN), as shown in Figure 2 and 2a.

Dynamic control of the on/off function is best accomplished with a mechanical

relay or open-collector/open-drain drive circuit. The drive circuit should be

able to sink appropriate current when activated and withstand appropriate

voltage when deactivated.

Figure 2. Driving the On/Off Control Pin with an Open-Collector Drive Circuit

+INPUT

COMMON

10kΩ

4.12kΩ

1.62kΩ

ON/OFF

CONTROL

Remote Sense

LSN D12 SIP Series DC/DC converters offer an output sense function on

pin 3.

The sense function enables point-of-use regulation for overcoming

moderate IR drops in conductors and/or cabling. Since these are non-isolated

devices whose inputs and outputs usually share the same ground plane,

sense is provided only for the +Output.

The remote sense line is part of the feedback control loop regulating the

DC/DC converter’s output. The sense line carries very little current and

consequently requires a minimal cross-sectional-area conductor. As such, it

is not a low-impedance point and must be treated with care in layout and

cabling. Sense lines should be run adjacent to signals (preferably ground),

and in cable and/or discrete-wiring applications, twisted-pair or similar tech-

niques should be used. To prevent high frequency voltage differences between

VOUT and Sense, we recommend installation of a 1000pF capacitor close to

the converter.

The sense function is capable of compensating for voltage drops between the

+Output and +Sense pins that do not exceed 10% of VOUT.

[VOUT(+) – Common] – [Sense(+) – Common] ≤ 10%VOUT

Power derating (output current limiting) is based upon maximum output cur-

rent and voltage at the converter's output pins. Use of trim and sense func-

tions can cause the output voltage to increase, thereby increasing output

power beyond the LSN's speciﬁ ed rating. Therefore:

(VOUT at pins) x (IOUT) ≤ rated output power

The internal 10.5Ω resistor between +Sense and +Output (see Figure 1)

serves to protect the sense function by limiting the output current ﬂ owing

through the sense line if the main output is disconnected. It also prevents

output voltage runaway if the sense connection is disconnected.

Note: Connect the +Sense pin (pin 3) to +Output (pin 4) at the DC/DC

converter pins, if the sense function is not used for remote regulation.

LSN-10A D12 Models

NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

Output Voltage Trimming

Allowable trim ranges for each model in the LSN D12 SIP Series are ±10%.

Trimming is accomplished with either a trimpot or a single ﬁ xed resistor. The

trimpot should be connected between +Output and Common with its wiper

connected to the Trim pin as shown in Figure 3 below.

A trimpot can be used to determine the value of a single ﬁ xed resistor

which can then be connected, as shown in Figure 4, between the Trim pin

and +Output to trim down the output voltage, or between the Trim pin and

Common to trim up the output voltage. Fixed resistors should have absolute

TCR’s less than 100ppm/°C to ensure stability.

Figure 4. Trim Connections Using Fixed Resistors

Note:

Install either a ﬁ xed

trim-up resistor

or a ﬁ xed trim-down

resistor depending upon

desired output voltage.

Output Overvoltage Protection

LSN D12 SIP Series DC/DC converters do not incorporate output overvolt-

age protection. In the extremely rare situation in which the device’s feedback

loop is broken, the output voltage may run to excessively high levels (VOUT =

VIN). If it is absolutely imperative that you protect your load against any and

all possible overvoltage situations, voltage limiting circuitry must be provided

external to the power converter.

Output Overcurrent Detection

Overloading the output of a power converter for an extended period of

time will invariably cause internal component temperatures to exceed their

maximum ratings and eventually lead to component failure. High-current-

carrying components such as inductors, FET's and diodes are at the highest

risk. LSN D12 SIP Series DC/DC converters incorporate an output overcur-

rent detection and shutdown function that serves to protect both the power

converter and its load.

If the output current exceeds it maximum rating by typically 70% (17 Amps) or

if the output voltage drops to less than 98% of it original value, the LSN D12's

internal overcurrent-detection circuitry immediately turns off the converter,

which then goes into a "hiccup" mode. While hiccupping, the converter will

continuously attempt to restart itself, go into overcurrent, and then shut down.

Under these conditions, the average output current will be approximately

400mA, and the average input current will be approximately 40mA. Once the

output short is removed, the converter will automatically restart itself.

Figure 3. Trim Connections Using a Trimpot

LOAD

20kΩ

5-10

Tu r n s

+INPUT

COMMON

+OUTPUT

TRIM

Trim

Down

Trim

LOAD

+INPUT

COMMON

+OUTPUT

TRIM

COMMON

Trim Equations

Note: Resistor values are in kΩ. Accuracy of adjustment is subject to

tolerances of resistors and factory-adjusted, initial output accuracy.

VO = desired output voltage. VONOM = nominal output voltage.

The equations below can be used as starting points for selecting speciﬁ c trim-

resistor values. Recall, untrimmed devices are guaranteed to be ±1% accurate.

Adjustment beyond the speciﬁ ed ±10% adjustment range is not recommended.

UP VO – VO NOM

RT (kΩ) = 1.46

DOWN VO NOM – VO

RT (kΩ) = – X

– X

1.82(VO – 0.8)

UP VO – VO NOM

RT (kΩ) = 3.72

DOWN VO NOM – VO

RT (kΩ) = – X

– X

4.64(VO – 0.8)

UP VO – VO NOM

RT (kΩ) = 6

DOWN VO NOM – VO

RT (kΩ) = – X

– X

7.5(VO – 0.8)

LSN-1/10-D12: X = 0.909

LSN-1.1/10-D12: X = 2.49

LSN-1.2/10-D12: X = 3.09

LSN-1.3/10-D12: X = 4.12

LSN-1.5/10-D12: X = 13.3

LSN-1.8/10-D12: X = 16.9

LSN-2/10-D12: X = 15.4

LSN-2.5/10-D12: X = 20

LSN-3.3/10-D12: X = 15

LSN-5/10-D12: X = 10

The on/off control function, however, can be externally inverted so that the

converter will be disabled while the input voltage is ramping up and then

"released" once the input has stabilized.

For a controlled start-up of one or more LSN-D12's, or if several output

voltages need to be powered-up in a given sequence, the On/Off Control pin

can be pulled high (external pull-up resistor, converter disabled) and then

driven low with an external open collector device to enable the converter.

Figure 2a. Inverting On/Off Control Pin Signal and Power-Up Sequencing

+INPUT

COMMON

10kΩ

4.12kΩ

5.6kΩ

1.62kΩ

ON/OFF

CONTROL

LSN-10A D12 Series NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

Thermal Considerations and Thermal Protection

The typical output-current thermal-derating curves shown below enable

designers to determine how much current they can reliably derive from each

model of the LSN D12 SIP's under known ambient-temperature and air-ﬂ ow

conditions. Similarly, the curves indicate how much air ﬂ ow is required to

reliably deliver a speciﬁ c output current at known temperatures.

The highest temperatures in LSN D12 SIP's occur at their output inductor,

whose heat is generated primarily by I2R losses. The derating curves were

developed using thermocouples to monitor the inductor temperature and

varying the load to keep that temperature below +110°C under the assorted

conditions of air ﬂ ow and air temperature. Once the temperature exceeds

+115°C (approx.), the thermal protection will disable the converter. Automatic

restart occurs after the temperature has dropped below +110°C.

Typical Performance Curves for LSN D12 SIP Series

LSN-1/10-D12

Efficiency vs. Line Voltage and Load Current

1 2 3 4 5 6 7 8 9 1

Load Current

(

)

Efficiency (%)

= 10.8V

= 12V

= 13.2V

–40 0 60 70 80 90 100 110

LSN-1/10-D12

Output Current vs. Ambient Temperature

(Vertical mount, air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

200 lfm

100 lfm

Output Reverse Conduction

Many DC/DC's using synchronous rectiﬁ cation suffer from Output Reverse

Conduction. If those devices have a voltage applied across their output before

a voltage is applied to their input (this typically occurs when another power

supply starts before them in a power-sequenced application), they will either

fail to start or self destruct. In both cases, the cause is the "freewheeling" or

"catch" FET biasing itself on and effectively becoming a short circuit.

LSN D12 SIP DC/DC converters do not suffer from Output Reverse Conduc-

tion. They employ proprietary gate drive circuitry that makes them immune

to applied output voltages.

All but the last two DUT's were vertical-mount models, and the direction of air

ﬂ ow was parallel to the unit in the direction from pin 11 to pin 1.

As you may deduce from the derating curves and observe in the efﬁ ciency

curves on the following pages, LSN D12 SIP's maintain virtually constant

efﬁ ciency from half to full load, and consequently deliver very impressive

temperature performance even if operating at full load.

Lastly, when LSN D12 SIP's are installed in system boards, they are obvi-

ously subject to numerous factors and tolerances not taken into account here.

If you are attempting to extract the most current out of these units under

demanding temperature conditions, we advise you to monitor the output-

inductor temperature to ensure it remains below +110°C at all times.

Thermal Performance for "H" Models

Enhanced thermal performance can be achieved when LSN D12 SIP's are

mounted horizontally ("H" models) and the output inductor (with its electrically

isolating, thermally conductive pad installed) is thermally coupled to a copper

plane/pad (at least 0.55 square inches in area) on the system board. Your

conditions may vary, however our tests indicate this conﬁ guration delivers a

16°C to 22°C improvement in ambient operating temperatures. See page 9

for thermal comparison of two horizontally mounted units.

LSN-10A D12 Models

NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

LSN-1.1/10-D12, LSN-1.2/10-D12, LSN-1.3/10-D12

Efficiency vs. Line Voltage and Load Current

123 45678910

Load Current (Amps)

Efficiency (%)

= 10.8V

= 12V

= 13.2V

–40 0 60 70 80 90 100 110

LSN-1.1/10-D12, LSN-1.2/10-D12, LSN-1.3/10-D12

Output Current vs. Ambient Temperature

(Vertical mount, air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

200 lfm

100 lfm

LSN-1.5/10-D12

Efficiency vs. Line Voltage and Load Current

123 45678910

Load Current (Amps)

Efficiency (%)

= 10.8V

= 12V

= 13.2V

LSN-1.8/10-D12

Efficiency vs. Line Voltage and Load Current

123 45678910

Load Current (Amps)

Efficiency (%)

= 10.8V

= 12V

= 13.2V

Typical Performance Curves for LSN D12 SIP Series

–40 0 60 70 80 90 100 110

LSN-1.5/10-D12

Output Current vs. Ambient Temperature

(Vertical mount, air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

200 lfm

100 lfm

–40 0 60 70 80 90 100 110

LSN-1.8/10-D12

Output Current vs. Ambient Temperature

(Vertical mount, air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

200 lfm

100 lfm

LSN-10A D12 Series NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

LSN-3.3/10-D12

Efficiency vs. Line Voltage and Load Current

123 45678910

Load Current (Amps)

Efficiency (%)

= 10.8V

= 12V

= 13.2V

LSN-2.5/10-D12

Efficiency vs. Line Voltage and Load Current

123 45678910

Load Current (Amps)

Efficiency (%)

= 10.8V

= 12V

= 13.2V

Typical Performance Curves for LSN D12 SIP Series

–40 0 50 60 70 80 90 100 110

LSN-2.5/10-D12

Output Current vs. Ambient Temperature

(Vertical mount, air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

200 lfm

100 lfm

–40 0 50 60 70 80 90 100 110

LSN-3.3/10-D12

Output Current vs. Ambient Temperature

(Vertical mount, air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

200 lfm

100 lfm

LSN-2/10-D12

Efficiency vs. Line Voltage and Load Current

123 45678910

Load Current (Amps)

Efficiency (%)

= 10.8V

= 12V

= 13.2V

–40 0 50 60 70 80 90 100 110

LSN-2/10-D12

Output Current vs. Ambient Temperature

(Vertical mount, air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

200 lfm

100 lfm

LSN-10A D12 Models

NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

LSN-5/10-D12

Efficiency vs. Line Voltage and Load Current

123 45678910

Load Current (Amps)

Efficiency (%)

= 10.8V

= 12V

= 13.2V

–40 0 40 50 60 70 80 90 100

LSN-5/10-D12

Output Current vs. Ambient Temperature

(Vertical mount, air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

200 lfm

100 lfm

–40 0 50 60 70 80 90 100 110

LSN-1/10-D12H (Horizontal Mount)

Output Current vs. Ambient Temperature

(Air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (

Natural Convection

200 lfm

100 lfm

–40 0 40 50 60 70 80 90 100

LSN-5/10-D12H (Horizontal Mount)

Output Current vs. Ambient Temperature

(Air flow direction from pin 11 to pin 1)

Output Current (Amps)

Ambient Temperature (°C)

Natural Convection

200 lfm

100 lfm

Input Reflected Ripple Current

(VIN = 12V, VOUT = 5V/10A, CIN/COUT = 22µF)

2µsec/div

20mA/div

Input Inrush Current

(VIN = 12V, 7000µF as Input Switch)

10µsec/div

20A/div

Typical Performance Curves for LSN D12 SIP Series

LSN-10A D12 Series NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

Dynamic Load Response

(VIN = 12V, VOUT = 5V/50 to 100% Load Step, CIN/COUT = 22µF)

100µs/div

20mV/div

Channel 2

Channel 1

Dynamic Load Response

(VIN = 12V, VOUT = 5V, 0 - 100% Load Step, CIN = 22µF, COUT = 2000µF OSCON)

100µs/div

50mV/div

Channel 2

Channel 1

Output Ripple Noise

(VIN = 12V, VOUT = 5V, Full Load, COUT = 22µF)

1µsec/div

10mV/div

Output Ripple/Noise

(VIN = 12V, VOUT = 5V, Full Load, COUT = 2000µF OSCON)

1µsec/div

10mV/div

Typical Performance Curves for LSN D12 SIP Series

Power-Up From VIN

(VIN = 12V, VOUT = 5V/10A, CIN = 22µF, Output Filter 22µF-700nH-150µF)

4msec/div

Channel 1: 2V/div Channel 2: 5V/div

Power-Up From VIN

(VIN = 12V, VOUT = 5V/10A, CIN = 22µF, COUT = 2000µF OSCON)

4msec/div

Channel 1: 2V/div Channel 2: 5V/div

LSN-10A D12 Models

NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

Output Hiccup

(VIN = 12V/Output Short, CIN/COUT = 22µF)

20msec/div

1V/div

(IIN = 39mA average, IOUT = 408mA average)

Short Circuit Output Current

(10A/div, Period = 72msec)

400µsec/div

10A/div

LSN-5/10-D12 Radiated Emissions

EN55022 Class B, 10 Meters

Converter Output = +5Vdc @ +10 Amps

–10

–20

Frequency (MHz)

100 1000

Radiated Emissions

EN 55022 Class B Limit

Radiated Emissions (dBµV/M)

–10

–20

Frequency (MHz)

100 1000

FCC Class B Limit

LSN-5/10-D12 Radiated Emissions

FCC Part 15 Class B, 3 Meters

Converter Output = +5Vdc @ 10 Amps

Radiated Emissions (dBµV/M)

Radiated Emissions

If you’re designing with EMC in mind, please note that all of DATEL’s

LSN D12 DC/DC Converters have been characterized for conducted and

radiated emissions in our EMI/EMC laboratory. Testing is conducted in an

EMCO 5305 GTEM test cell utilizing EMCO automated EMC test software.

Conducted/Radiated emissions are tested to the limits of FCC Part 15, Class

B and CISPR 22 (EN 55022), Class B. Correlation to other speciﬁ cations can

be supplied upon request. The corresponding emissions plots to FCC and

CISPR 22 for model LSN-5/10-D12 appear below. The published EMC test

report is based on results with the highest possible output power model and

is therefore representative of the whole LSN-D12 series. Contact DATEL’s

Applications Engineering Department for more details.

EMI CONDUCTED/RADIATED EMISSIONS

100

Frequency (MHz)

0.1 1.0 10.0

LSN-5/10-D12 Conducted Emissions

FCC Part 15 Class B, EN55022 Class B Limit, +12 Vdc @ 4.5A

Converter Output = +5Vdc @ 10 Amps

Conducted Emissions (dBµV/M)

Conducted Emissions

FCC Class B Limit

EN55022 Class B Limit

Typical Performance Curves for LSN D12 SIP Series

LSN-10A D12 Series NON-ISOLATED, 10-50W SIP DC/DC CONVERTERS

DATEL makes no representation that the use of its products in the circuits described herein, or the use of other technical information contained herein, will not infringe upon existing or future patent rights. The descriptions contained herein

do not imply the granting of licenses to make, use, or sell equipment constructed in accordance therewith. Speciﬁ cations are subject to change without notice. The DATEL logo is a registered DATEL, Inc. trademark.

DATEL (UK) LTD. Tadley, England Tel: (01256)-880444

DATEL S.A.R.L. Montigny Le Bretonneux, France Tel: 01-34-60-01-01

DATEL GmbH München, Germany Tel: 89-544334-0

DATEL KK Tokyo, Japan Tel: 3-3779-1031, Osaka Tel: 6-6354-2025

DATEL, Inc. 11 Cabot Boulevard, Mansﬁ eld, MA 02048-1151

Tel: (508) 339-3000 (800) 233-2765 Fax: (508) 339-6356

Internet: www.datel.com Email: sales@datel.com

ISO 9001 REGISTERED

INNOVATION and EX C ELL E N C

DS-0514E 6/03

Maximum Rated Output

Current in Amps

PART NUMBER STRUCTURE

Non-Isolated SIP

Output

Conﬁ guration:

L = Unipolar

Low Voltage

Nominal Output Voltage:

1, 1.1, 1.2, 1.3, 1.5, 1.8, 2, 2.5, 3.3

or 5 Volts

Input Voltage Range:

D12 = 10.8 to 13.2 Volts

(12V nominal)

L SN 10-/D12 B

1.8

B Sufﬁ x:

No Remote Sense

(Pin 3 removed)

Functional Options

Remote Sense Pin Removed ("B" sufﬁ x)

These devices have their +Sense pin (pin 3) removed, and the feedback

loop is closed through the +VOUT path. The 10.5Ω resistor in Figure 1 is

installed in both standard and "B" models. See the Output Sense Function.

Horizontal Mounting ("H" sufﬁ x)

This packaging conﬁ guration reduces above-board height to 0.35" (8.89mm),

including the isolating pad. For "H" models, a thermally conductive, electri-

cally insulating "pad" is factory installed on the output inductor. The pad

material is Bergquist Sil Pad 400. The pad size is 0.4 x 0.5 x 0.009 inches

(10.16 x 12.7 x 0.23mm). This conﬁ guration can signiﬁ cantly improve thermal

performance. See Thermal Derating for details.

Reversed pin vertical mounting ("J" sufﬁ x)

This additional mechanical conﬁ guration consists of a low-proﬁ le pin header

attached to the reverse side of the converter. It allows the LSN series to be

mechanically compatible with competitors' "keep out area."

Other Options and Modiﬁ cations

Other options include a positive polarity (pull low to disable) on the On/Off

Control. Contact DATEL directly to discuss these and other possible modiﬁ -

cations.

Examples

LSN-1.8/10-D12 Vertical-mount. Sense function on pin 3. No pin 9.

LSN-1.8/10-D12B Vertical-mount. Pin 3 (+Sense) removed. No pin 9.

LSN-1.8/10-D12H Horizontal-mount. Sense function on pin 3. No pin 9.

LSN-1.8/10-D12BH Horizontal-mount. Pin 3 (+Sense) removed. No pin 9.

LSN-1.8/10-D12J Reverse pin vertical-mount. Sense function on pin 3.

No pin 9.

H Sufﬁ x:

Horizontal Mount

J Sufﬁ x:

Reversed Pin

Vertical Mount