LYT3325D_技术文档

LYT3314-3328

LYTSwitch-3 Family

Single-Stage LED Driver IC with Combined PFC and

Constant Current Output for Outstanding TRIAC Dimming

in Isolated and Non-Isolated Topologies

Product Highlights

Combined Single-Stage PFC + Accurate CC Output

• Less than ±3% CC regulation over line and load

L

• Power Factor >0.9

• Ensures monotonic VA reduction with TRIAC phase angle

• Low THD, 15% typical for dimmable bulbs, as low as 7% in

T

LYTSwitch-3

BL

L

D

S

N

optimized designs

CONTROL

BS

DS

Advanced Integrated TRIAC Dimmer Detection

• Detects leading-edge and trailing-edge TRIAC dimmers

• High-efﬁciency mode when no dimmer is present

• Selectable dimming proﬁle increases design ﬂexibility

• Fast turn-on (<500 ms)

FB

BP

OC

T

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• Low pop-on and dead-travel

• Active bleeder drive for widest dimmer compatibility

Figure 1. Simpliﬁed Schematic (Buck).

Design Flexibility

• Supports buck, buck-boost, tapped buck-boost, boost, isolated and

non-isolated ﬂyback

• Up to 20 W output

Output Power Table

Product²

Output Power¹

Highest Reliability

• No electrolytic bulk capacitors or optoisolators for increased lifetime

• Comprehensive protection features

• Input and output overvoltage

• Output short-circuit and open-loop protection

• Advanced thermal control

• Thermal foldback ensures that light continues to be delivered at

elevated temperatures

• End-stop shutdown provides protection during fault conditions

85-132 VAC or 185-265 VAC

LYT33x4D³

LYT33x5D

LYT33x6D

LYT33x8D

5.7 W

8.8 W

12.6 W

20.4 W

Table 1. Output Power Table (Buck Topology).

Description

Notes:

1. Maximum practical continuous power in an open frame design with adequate

heat sinking, measured at 50˚C ambient (see Key Applications Considerations

for more information).

The LYTSwitch™-3 family is ideal for single-stage power factor

corrected constant current LED bulbs and downlighters.

2. Package: D: SO-16B.

Each device incorporates a high-voltage power MOSFET and discon-

tinuous mode, variable frequency variable on-time controller. The

controller also provides cycle-by-cycle current limit, output OVP, line

overvoltage, comprehensive protection features, plus advanced

thermal management circuitry.

3. ”x” digit describes V_DSON(MAX)of the integrated switching MOSFET,

650 V = 1, 725 V = 2.

All LYTSwitch-3 ICs have a built-in TRIAC detector that discriminates

between leading-edge and trailing-edge dimmers. This capability

together with load monitoring circuitry regulates bleeder current during

each switching cycle. The controller disables the bleeder circuit

completely if no dimmer is detected, signiﬁcantly increasing efﬁciency.

Figure 2. SO-16B (D Package).

The combination of a low-side switching topology, cooling via electroni-

cally quiet SOURCE pins and frequency jitter ensure extremely low EMI.

This reduces the size of the input ﬁlter components – greatly reducing

audible noise during dimming.

The part numbers shown in Table 1 describe 4 different power levels and

two MOSFET voltage options to cost-optimize designs while EcoSmart^TM

switching technology insures maximum efﬁciency for each device size

and load condition.

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April 2016

This Product is Covered by Patents and/or Pending Patent Applications.

LYT3314-3328

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Figure 3. Block Diagram.

2

Rev. D 04/16

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LYT3314-3328

FEEDBACK (FB) Pin

Pin Functional Description

In normal operation and full conduction the preset threshold on the

FEEDBACK pin is 300 mV. This threshold gets reduced linearly with

conduction angle until a minimum level is reached.

LINE-SENSE (L) Pin

LINE-SENSE pin implements input voltage waveform detection:

conduction angle is detected accurately since SOURCE pin is referenced

to bulk capacitor ground. Input OVP is activated when LINE-SENSE pin

current exceeds the predetermined threshold.

Cycle skipping is triggered when voltage on this pin exceeds 600 mV.

BYPASS (BP) Pin

5.25 V supply rail.

BLEEDER CURRENT SENSE (BS) Pin

BLEEDER CURRENT SENSE pin measures the total input current –

active bleeder current plus switch current. This current is sensed in

order to keep TRIAC current above its holding level. This is achieved by

modulating the bleeder dissipation.

OUTPUT COMPENSATION (OC) Pin

Output OVP for all topologies. Output voltage compensation for indirect

output current sense topologies.

DRAIN (D) Pin

High-voltage internal MOSFET (725 V or 650 V).

R_BS(W)

Dim Curve

Load Shut Down (LSD)

SOURCE (S) Pin:

Power and signal ground.

6 k

Max. Dim Curve

Min. Dim Curve

No

12 k

24 k

Yes

Table 2. BS Pin Resistor Programming.

ꢀ ꢁꢂꢃꢄꢂꢅꢆ ꢇꢈꢉ-1ꢊꢋꢌ

DRIVER CURRENT SENSE (DS) Pin

DRIVER CURRENT SENSE pin senses the driver current. This current is

used to deduce output current: it is multiplied by the input voltage and

the result is then divided by the output voltage to obtain output current.

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R_DS(W)

Topology

6 k

Buck, Buck-Boost, Isolated Flyback

24 k

Non-Isolated Flyback

1

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4

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Table 3. Topology Selection Resistor.

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BLEEDER CONTROL (BL) Pin

BLEEDER CONTROL pin drives the external bleeder transistor in order to

maintain the driver input current above the holding current of the

dimmer TRIAC.

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Figure 4. Pin Conﬁguration.

3

Rev. D 04/16

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LYT3314-3328

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Figure 5. Typical Schematic Buck (Low-Line).

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Figure 6. Typical Schematic Buck-Boost (High-Line).

4

Rev. D 04/16

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LYT3314-3328

Applications Example

DER-524 8 W A19 LED Bulb Driver Dimmable, Tight

Regulation, High Power factor, Low ATHD Design

Example

RTN

L1

R7

1 mH

T1

1

150 Ω

2 W

R32

3 kΩ

2 W

R8

R20

2 MΩ

1%

C10

120 µF

80 V

1 kΩ

1 W

R19

82 kΩ

C4

C5

100 nF

400 V

47 nF

400 V

C3

47 nF

400 V

R18

2 MΩ

1%

2

+V

R9

2 kΩ

2 W

BR1

B10S-G

1000 V

D3

RF1

47 Ω

2 W

STTH1R06A

600 V

L

Q2

PN222A

RV1

275 VAC

LYTSwitch-3

U1

BL

L

D

LYT3325D

R11

24 kΩ

CONTROL

BS

DS

N

D2

R13

FB

BP

OC

S

BAV21W-7-F

6.04 kΩ

T1

8

1%

C2

8.2 nF

50 V

R4

20 Ω

R16

C6

178 kΩ

R15

39.2 kΩ

1%

C8

150 nF

25 V

C11

10 µF

1%

22 µF

10 V

50 V

R1

3.9 Ω

R14

6.2 kΩ

7

C7

22 µF

16 V

PI-7779-021016 HLBB

R12

4.3 Ω

1%

Figure 7. DER-524 8 W, 72 V, 115 mA Non-Isolated Dimmable A19 LED Bulb Driver using LYT3325D.

The circuit shown in Figure 7 is conﬁgured as a buck-boost power

supply utilizing the LYT3325D from the LYTSwitch-3 family of ICs.

This type of LED driver conﬁguration is common for dimmable bulb

applications where high dimmer compatibility, accurate regulation,

high efﬁciency, high power factor and low ATHD are required along

with low component count for high reliability. The output can drive

an LED load from 68 V to 76 V with a constant output current of

115 mA ±3% across an input range of 195 VAC to 264 VAC and can

operate in maximum ambient temperature of 100 ºC with good margin

below the thermal foldback protection point. It has an efﬁciency of

greater than 86%, very low ATHD% (less than 20%) and high power

factor of greater than 0.9 measured across the input range.

conduction mode inherently eliminates reverse current from the

output diode when the power MOSFET is in the OFF-state reducing

high frequency noise and allowing the use of a simpler, smaller EMI

ﬁlter which also improves efﬁciency.

Input Filter

AC input power is rectiﬁed by bridge BR1. A 1000 V voltage rating is

recommended (the maximum clamp voltage for a typical 275 V

varistor is 720 V). The rectiﬁed DC is ﬁltered by the input capacitors

C4 and C5. Too much capacitance degrades power factor and ATHD,

so the values of the input capacitors were adjusted to the minimum

values necessary to meet EMI with a suitable margin. Inductor L1,

C4 and C5 form a π (pi) ﬁlter, which attenuates conducted differential

and common mode EMI currents. Optional resistor R10 across L1

damps the Q of the ﬁlter inductor to improve ﬁltering without

reducing low frequency attenuation. Fuse RF1 in Figure 7 provides

protection against catastrophic failures such as short-circuit at the

input. For cost reduction, this can be replaced by a fusible resistor

(typically a ﬂame proof wire-wound type) which would need to be

rated to withstand the instantaneous dissipation induced when

charging the input capacitance when ﬁrst connected to the input line.

Circuit Description

The LYTSwitch-3 device (U1 - LYT3325D) combines a high-voltage

power MOSFET, variable frequency and on-time control engine, fast

start-up, selectable dimming curves with load shutdown at deep

dimming and protection functions including line and output overvolt-

age into a single package, greatly reducing component count. The

integrated 725 V power MOSFET provides a large drain voltage

margin in high-line input AC applications thus increasing reliability.

A 625 V power MOSFET option is also offered to reduce cost in

applications where the voltage stress on the power MOSFET is lower.

Conﬁgured to operate as a discontinuous conduction mode buck-

boost converter, U1 provides high power factor and very low ATHD

via its internal control algorithm (the design also features low input

capacitance to further reduce THD and increase PF). Discontinuous

Selection of fuse RF1 in Figure 7 type and rating is dependent on input

surge requirements. Typical minimum requirement for bulb applica-

tion is 500 V differential surges. This design meets a 1 kV surge

speciﬁcation, so a 47 W fusible resistor in Figure 7 was used. A fast-

blow fuse with high ampere energy (I²T) rating could also be used.

5

Rev. D 04/16

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LYT3314-3328

LYTSwitch-3 Output Regulation

capacitor should be greater than 7 V. The capacitor can be a ceramic

or electrolytic type, but tolerance should be less than 50%. The

capacitor must be physically located close to BYPASS and SOURCE

pins for effective noise decoupling.

In order to maintain very tight output current regulation – within

±3%, the FEEDBACK (FB) pin voltage (with an appropriately selected

low-pass ﬁlter comprising R15 and C8) is compared to a preset

average feedback voltage (V_FB) of 300 mV. When the detected signal

is above or below the preset average V_FBthreshold voltage, the

onboard averaging-engine will adjust the frequency and/or on-time to

maintain regulation.

Output Rectiﬁcation

During the switching OFF-state the output from the transformer main

winding is rectiﬁed by D3 and ﬁltered by C10. An ultrafast 1 A, 600 V

with 35 ns reverse recovery time (t_RR) diode was selected for efﬁciency.

The value of the output capacitor C10 was selected to give peak-to-

peak LED ripple current equal to 30% of the mean value. However,

the output ripple current will also depend on the type and impedance

characteristic of the LED load, so it is recommended to, use the

actual LED load for sizing the capacitor value for the output ripple

current. For designs where lower ripple is desirable the output

capacitance value can be increased unlike traditional power supplies,

low ESR capacitors are not required for the output stage of LED

designs.

The bias winding voltage is proportional to the output voltage

(controlled by the turns-ratio between the bias supply and output-

main winding). This allows the output voltage to be monitored

without the need for output-side feedback components. Resistor R16

in Figure 7 converts the bias voltage into a current which is fed into

the OUTPUT COMPENSATION (OC) pin of U1. The OUTPUT COMPEN-

SATION pin current is also used to detect output overvoltage which is

set to 30% above the nominal output voltage. Once the current

exceeds the I_OOVthreshold the IC will trigger a latch, which disables

switching which prevents the output from rising further. An AC

recycle is needed to reset this protection mode once triggered.

A small output pre-load resistor R19 discharges the output capacitor

when the driver is turned off, giving a relatively quick and smooth

decay of the LED light. Recommended pre-load power dissipation is

≤0.5% of the output power.

In order to provide line input voltage information to U1 the rectiﬁed

input AC voltage is fed into the LINE SENSE (L) pin of U1 as a current

via R20 and R18. This sensed current is also used by U1 to detect

the input zero crossing, type of dimmer (i.e. leading or trailing edge)

connected to the input and set the input line overvoltage protection

threshold. In a line overvoltage condition once this current exceeds

the I_LOV+threshold, the IC will instantaneously disable switching to

protect the power MOSFET from further voltage stress. The IC will

start switching as soon as the line voltage drops to safe levels

indicated by the LINE SENSE pin current dropping by 5 µA.

Phase-Cut Dimming

The biggest challenge in designing dimmable LED bulb is high

compatibility with a broad range of dimmer types and power rating.

As different type of dimmers have different minimum loading

requirements the dimmable LED bulb may manifest varying incompat-

ibility behavior depending on the dimming conditions from light

ﬂickering or shimmering, ghosting, huge pop-on to low dim ratio.

There are two main types of phase-cut dimmers namely leading edge

(Figure 8) and trailing edge (Figure 9). Each type has its own

characteristic and nuances that particularly makes it challenging for

LED driver to achieve high compatibility and no one can ever know

what type of dimmer an LED bulb will be used with therefore it is

imperative that the designer must use a controller with bleeder with

the capability to satisfy the requirement depending the type of the

dimmer.

The primary switched current is sensed via R12 and ﬁltered with C6.

The signal is fed into the DRIVER CURRENT SENSE (DS) pin. A low

ESR ceramic capacitor of at least 10 µF is recommended for capacitor

C6 for better regulation and reduced the AC RMS loss across R6. The

DRIVER CURRENT SENSE pin program resistor R13 is 6.04 kW 1% for

primary-side regulation for indirectly sensing of the output current.

The internal frequency/on-time engine inside the LYTSwitch-3 IC

combines the OUTPUT COMPENSATION pin current, the LINE SENSE

pin current and the DRIVER CURRENT SENSE pin current information

to deduce the FEEDBACK pin signal. This is compared to an internal

V_FBthreshold to maintain accurate constant output current.

The requirement to provide ﬂicker-free output dimming with low-cost,

TRIAC-based, leading edge phase dimmers introduces a number of

trade-off in the design. Due to the much lower power consumed by

LED based lighting the current drawn by the overall lamp is below the

holding current of the TRIAC within the dimmer. This causes

undesirable behaviors such as limited dimming range and/or ﬂickering.

The relatively large impedance the LED lamp presents to the line

allows signiﬁcant ringing to occur due to the inrush current charging

the input capacitance when the TRIAC turns on. This too can cause

similar undesirable behavior as the ringing may cause the TRIAC

current to fall to zero and turn-off.

It is important to note that for accurate output current regulation the

use of 1% tolerance for LINE SENSE pin resistors (R20 and R18) is

recommended. This recommendation also applies to OUTPUT

COMPENSATION pin resistor R16, FEEDBACK pin resistor R15

(capacitor C8 at least X7R type), and DRIVER CURRENT SENSE pin

resistor R12 and R13.

Diode D2 and C11 provides a bias supply for U1 from an auxiliary

winding on the transformer. Bias supply recommended voltage level

is 20 V, when this voltage drops at low conduction angle during

dimming would be high enough to maintain supply for U1. Filter

capacitor C11 should be sized to ensure a low ripple voltage.

Capacitor C7 serves as local decoupling for the BYPASS pin of U1

which is the supply pin for the internal controller. Current via R14 is

typically limited to 2.5 mA. During start-up, C7 is charged to ~5.3 V

from an internal high-voltage current source internally fed from the

DRAIN pin. This allows U1 to start switching even at low conduction

angle when in dimming. After start-up the operating supply current is

provided from the bias supply via R14. The recommended value for

the BYPASS pin capacitor C7 is 22 µF. The voltage rating for the

Figure 9 shows the line voltage and current at the input of the power

supply with a trailing edge dimmer. In this example, the dimmer

conducts at 90 degrees. Many of these dimmers use back-to-back

connected power FETs rather than a TRIAC to control the load. This

eliminates the holding current issue of TRIACs and since the

conduction begins at the zero crossing, high current surges and line

ringing are minimized. Typically these types of dimmers do not

require damping circuits. However, would require a bleeder circuit to

provide a low impedance path for the internal supply to recharge and

reset its internal controller in order to operate normally and avoid

misﬁring for the succeeding cycle of the incoming input.

6

Rev. D 04/16

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LYT3314-3328

ꢈ1

L

Rꢅ

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Figure 8. Typical Voltage and Current Waveform and Schematic of a TRIAC-Based Leading Edge Dimmer.

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Figure 9. Typical Voltage and Current Waveforms and Schematic of a MOSFET-Based Trailing Edge Dimmer.

LYTSwitch-3 Smart Active Bleeder

current falls below the holding current thus maintaining the current

set by the resistor R1. The holding current can be set using the

equation R1 = 120 mV / A. For this design (DER-524) it is 30 mA.

Bleeder resistors R9 and R32 recommended total value is 5 kW with

2 W power rating each resistor for high-line application (1.2 kW total

for low-line at 50 mA holding current).

To overcome the challenges of designing for dimmable LED driver

with high compatibility on any type of dimmer, LYTSwitch-3 family

features a built-in TRIAC detector that is able to discriminate between

leading-edge and trailing-edge dimmers. This capability together

with load monitoring circuitry enables the controller to adjust bleeder

operation during each switching cycle to ensure a TRIAC input

impedance, or to disable the bleeder circuitry completely if no

dimmer is detected (signiﬁcantly increasing efﬁciency). The active

bleeder also helps in keeping the input current above the TRIAC

holding and latching current while the input current corresponding to

the effective driver resistance increases during each AC half-cycle.

Capacitor C2 and degenerative resistor R4 serve as stabilizing

network for the bleeder transistors for optimized dimming perfor-

mance. Resistor R4 typical range of value is 20 – 47 W while C2 is

between 4.7 – 22 nf.

Passive Bleeder and Damper

Both capacitor C3 and resistor R8 together with fusible resistor RF1

and damper R7 act as damper reducing the ringing current induced

by the spike of current charging the input bulk capacitors after the

TRIAC ﬁred at the onset of input AC. The value of C3 is typically

from 47 nf to 220 nf, while R8 can be between 470 W to 1 kW.

The LYTSwitch-3 ICs provide excellent dimming performance with its

close loop smart bleeder function. Transistor Q1 together with Q2 in

emitter follower connection, function as a high gain active switch that

pulls current from the input via R9 and R32. This maintains the

holding current and latching current necessary to keep the TRIAC on

during the entire input cycle. The analog signal from the BLEEDER

CONTROL (BL) pin of U1 drives Q1 and Q2 linearly when the input

7

Rev. D 04/16

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LYT3314-3328

and enables the use of small and simple pi (π) ﬁlter. It also allows

simple magnetic construction where the main winding can be wound

continuously using the automated winding approach preferred for

low-cost manufacturing. The recommended location of the EMI ﬁlter

is after the bridge rectiﬁer. This allows the use of regular ﬁlm

capacitors as opposed to more expensive safety rated X-capacitors

that would be required if the ﬁlter is placed before the bridge.

Key Design Considerations

Device Selection

The data sheet power table (Table 4) represents the maximum

practical continuous output power that can be delivered in an open

frame design with adequate heat sinking.

Output Power Table

Surge Immunity Consideration

This design assumed a differential surge requirement of up to 1 kV

which can be met easily with LYTSwitch-3’s very accurate line

overvoltage protection and a MOV (RV1).

Output Power

Product

85-132 VAC or 185-265 VAC

LYT33x4D

LYT33x5D

LYT33x6D

LYT33x8D

5.7 W

8.8 W

Thermal and Lifetime Considerations

Lighting applications present thermal challenges to the driver. In

many cases the LED load dissipation determines the working ambient

temperature experienced by the drive. Thermal evaluation should be

performed with the driver inside the ﬁnal enclosure. Temperature

has a direct impact on driver and LED lifetime. For every 10 °C rise in

temperature, component life is reduced by a factor of 2. Therefore it

is important to verify and optimize the operating temperatures of all

components.

12.6 W

20.4 W

Table 4.

Output Power Table.

DER-524 is an 8 W LED dimmable driver. Where LYT3325D was

chosen for its higher voltage power MOSFET rating of 725 V because

the topology chosen was a buck-boost and the speciﬁcation called for

a maximum input voltage of 264 VAC. In other applications where

surge and line voltage conditions allow, it may be possible to use the

650 V power MOSFET option to reduce design cost without impacting

reliability.

Provide enough spacing between bleeder and damper components

for better natural heat convection cooling.

Quick Design Checklist

Maximum Drain Voltage – Verify that the peak Drain voltage stress

(VDS) does not exceed 725 V under all operating conditions, including

start-up and fault conditions.

Magnetics Design

A very common core type was selected, an EE10 with ferrite core

material and a wide winding window that allowed better convection

cooling for the winding.

Maximum Drain Current – Measure the peak Drain current under all

operation conditions (including start-up and fault conditions). Look for

transformer saturation (usually occurs at highest operating ambient

temperatures). Verify that the peak current is less than the stated

Absolute Maximum Rating in the data sheet.

To ensure that discontinuous conduction mode (DCM) operation of

LYTSwitch-3 is maintained over line input and inductance tolerance

variations that is needed for tight output current regulation, it is

recommended that the LYTSwitch-3 PIXls spreadsheet located at

PI Expert online (https://piexpertonline.power.com/site/login) should

be used for magnetics calculations.

Thermal Check – At maximum output power, for both minimum and

maximum line voltage and maximum ambient temperature; verify

that temperature speciﬁcations are not exceeded for the LYTSwitch-3,

transformer, output diodes, output capacitors and clamp components.

EMI Considerations

Total input capacitance affects PF and ATHD – increasing the value

will degrade performance. With LYTSwitch-3 the combination of a

low-side switching conﬁguration and frequency jitter reduces EMI

8

Rev. D 04/16

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LYT3314-3328

As shown in Figure 10, minimize the loop areas of the following

switching circuit elements to lessen the creation of EMI.

PCB Layout Considerations

The EMI ﬁlter components should be located close together to improve

ﬁlter effectiveness. Place the EMI ﬁlter components C4 and L1 as far

away as possible from any switching nodes on the circuit board

especially U1 drain node, output diode (D3) and the transformer (T1).

• Loop area formed by the transformer output winding (T1), output

rectiﬁer diode (D3) and output capacitor (C10).

• Loop area formed by transformer bias winding (T1), rectiﬁer diode

(D2) and ﬁlter capacitor (C11).

Care should be taken in placing the components on the layout that

are used for processing input signals for the feedback loop – any high

frequency noise coupled to the signal pins of U1 may affect proper

system operation. The critical components in DER-524 are R18, R16,

C8, R15, R13 and R11. It is highly recommended that these compo-

nents be placed very close to the pins of U1 (to minimize long traces

which could serve as antenna) and far away as much as possible from

any high-voltage and high current nodes in the circuit board to avoid

noise coupling.

• Loop area formed by input capacitor (C5), sense resistor R12,

internal power MOSFET (U1) and transformer (T1) main winding.

Lastly, unlike discrete MOSFET designs where heat sinking is through

the drain tab and which generates signiﬁcant EMI, LYTSwitch-3 ICs

employ low-side switching and the ground potential SOURCE pins are

used for heat sinking. This allows the designer to maximize the

copper area for good thermal management but without having the

risk of increased EMI.

Design Tools

The BYPASS pin supply capacitor C7 should be placed directly across

BYPASS pin and SOURCE pin of U1 for effective noise decoupling.

Up-to-date information on design tools can be found at the Power

Integrations web site: www.power.com

DRꢝꢍꢜR ꢛꢦRRꢜꢥꢧ

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Rꢢꢉ ꢛꢓ

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ꢛ10

Dꢀꢁꢂeꢃ

Reꢄꢅꢄꢆꢇꢃꢄ

Rꢈ1ꢉ Rꢊ

Reꢄꢅꢄꢆꢇꢃ R1ꢓ

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ꢋꢌꢍ

Rꢍ1

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Reꢄꢅꢄꢆꢇꢃ R1ꢡ

ꢀꢘꢒ ꢛꢢ

ꢐꢗꢂꢀꢄꢄ ꢀꢘꢒ ꢐꢅꢀꢄ

ꢙꢚꢂꢂꢑꢗ ꢛꢀꢂꢀꢏꢅꢆꢇꢃꢄ

ꢛꢊꢉ ꢛ11

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ꢌꢦꢧꢣꢦꢧ

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Reꢄꢅꢄꢆꢇꢃ R16

ꢐꢭꢣꢎꢙꢙ ꢣꢅꢘ

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ꢣꢝꢤꢊꢢ6ꢕꢤ0ꢔ0416

Figure 10. Single-Side PCB Layout Example Showing the Arrangement and Location of Critical Components.

9

Rev. D 04/16

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LYT3314-3328

Absolute Maximum Ratings^(1,3)

DRAIN Pin Voltage:

LYT331x............................-0.3 V to 650 V Notes:

LYT332x ...........................-0.3 V to 725 V

1. All voltages referenced to Source, T_A= 25 °C.

2. 1/16 in. from case for 5 seconds.

DRAIN Pin Peak Current⁽⁴⁾LYT3314............................ 1.85 A (2.28 A)

LYT3324 ........................... 1.44 A (2.33 A)

3. The Absolute Maximum Ratings speciﬁed may be applied, one at a

time without causing permanent damage to the product. Exposure

to Absolute Maximum Ratings for extended periods of time may

affect product reliability.

4. The higher peak Drain current (in parentheses) is allowed while the

Drain voltage is simultaneously less than 400 V for 725 V integrated

MOSFET version, or less than 325 V for 650 V integrated MOSFET

version.

LYT3315 ........................... 2.39 A (2.95 A)

LYT3325 ............................1.95 A (3.16 A)

LYT3316 ........................... 3.25 A (4.00 A)

LYT3326 ........................... 2.64 A (4.35 A)

LYT3318 ........................... 5.06 A (6.30 A)

LYT3328 ............................4.16 A (6.86 A)

BP, BS, DS, BL, OC, L DS, FB Pin Voltage.....................-0.3 V to 6.5 V

Lead Temperature⁽²⁾.............................................................. 260 °C

Storage Temperature...................................................-65 to 150 °C

Operating Junction Temperature.................................. -40 to 150 °C

Thermal Resistance

Thermal Resistance: SO-16B Package:

Notes:

(q_JA)..................................................78 °C/W⁽²⁾1. Measured on the SOURCE pin close to plastic interface.

(q_JA) .................................................68 °C/W⁽³⁾2. Soldered to 0.36 sq. inch (232 mm²) 2 oz. (610 g/m²) copper clad,

(q_JC)⁽¹⁾...............................................43 °C/W

with no external heat sink attached.

3. Soldered to 1 sq. in. (645 mm²), 2 oz, (610 g/m²) copper clad.

Conditions

SOURCE = 0 V

T_J= -40 °C to +125 °C

Parameter

Symbol

Min

Typ

Max

Units

(Note C) (Unless Otherwise Speciﬁed)

Control Functions

Average

T_J= 25 °C

115.3

124

8

132.7

kHz

%

Maximum

Output Frequency

f_MAX

Peak-to-Peak Jitter

Average

T_J= 0 °C to 125 °C

40

8

kHz

%

Minimum

Output Frequency

f_MIN

Peak-to-Peak Jitter

Frequency Jitter

Modulation Rate

f_M

See Note A

1.76

kHz

Maximum On-Time

Minimum On-Time

FEEDBACK Pin Voltage

T_ON(MAX)

T_ON(MIN)

V_FB

T_J= 25 °C

5.75

0.95

291

6.25

1.05

300

6.75

1.15

309

µs

mV

FEEDBACK Pin Voltage

Triggering Cycle

Skipping

V_FB(SK)

600

mV

FEEDBACK Pin

Overvoltage Threshold

V_FB(OV)

2000

FEEDBACK Pin

Undervoltage Threshold

V_FB(UV)

I_FB

22

mV

Feedback Pull-Up Current

-1.3

-1.0

-0.7

µA

10

Rev. D 04/16

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LYT3314-3328

Conditions

SOURCE = 0 V

T_J= -40 °C to +125 °C

Parameter

Symbol

Min

Typ

Max

Units

(Unless Otherwise Speciﬁed)

Control Functions (cont.)

V_FB(ON)> V_FB> V_FB(SK)

(MOSFET not switching)

I_S1

0.8

0.9

1.0

1.2

mA

LYT3314

LYT3324

LYT3315

1.0

1.3

DRAIN Supply Current

MOSFET Switching

LYT3325

LYT3316

LYT3326

LYT3318

LYT3328

LYT33x4

LYT33x5-8

LYT33x4

LYT33x5-8

1.1

1.4

I_S2

at f_MAX

mA

1.1

1.4

1.1

1.4

1.2

1.5

1.3

1.6

-8.5

-11.5

-6.5

-8.8

4.75

-7.5

-9.5

-5.2

-6.8

5.00

-6.0

-7.5

-4.0

-4.8

5.25

BYPASS Pin

Charge Current

I_CH1

V_BP= 0 V, T_J= 25 °C

V_BP= 4 V, T_J= 25 °C

mA

BYPASS Pin

Charge Current

I_CH2

mA

V

BYPASS Pin Voltage

V_BP

BYPASS Pin

Shunt Voltage

V_SHUNT

I_BP= 5 mA

5.1

4.4

5.30

4.6

5.5

4.8

BYPASS Pin Power-Up

Reset Threshold Voltage

V_BP(RESET)

V

Circuit Protection

Current Limit

di/dt = 662 mA/µs

T_J= 25 °C

LYT33x4

LYT33x5

LYT33x6

LYT33x8

843

1232

1767

2860

130

907

1325

1900

3075

970

1418

2033

3290

di/dt = 974 mA/µs

T_J= 25 °C

I_LIMIT

mA

di/dt = 1403 mA/µs

T_J= 25 °C

di/dt = 2239 mA/µs

T_J= 25 °C

Leading Edge

Blanking Time

t_LEB

T_ILD

T_FB

T_J= 25 °C

165

160

142

ns

°C

Current Limit Delay

T_J= 25 °C, See Note A

See Note A

Thermal Foldback

Temperature

138

155

146

165

Thermal Shutdown

Temperature

T_SD

See Note A

160

°C

Thermal Shutdown

Hysteresis

T_SD(H)

See Note A

T_J= 25 °C

75

°C

ns

SOA Switch ON-Time

T_ON(SOA)

610

690

11

Rev. D 04/16

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LYT3314-3328

Conditions

SOURCE = 0 V

T_J= -40 °C to +125 °C

Parameter

Symbol

Min

Typ

Max

Units

(Unless Otherwise Speciﬁed)

Circuit Protection (cont.)

Auto-Restart Current

Threshold for Output

Undervoltage

I_OUV

T_J= 25 °C

40

52

58

µA

Threshold

T_J= 25 °C

116

120

5

124

Current Threshold for

Input Overvoltage

I_LOV+

Hysteresis

Latch-Off Current

Threshold for Output

Overvoltage

I_OOV

T_J= 25 °C

127

134

144

µA

LINE-SENSE Pin Voltage

Output

V_L

I_L= 100 µA, T_J= 25 °C

2.05

2.25

2.45

V

OUTPUT COMPENSATION

Pin Voltage

I_OC= 100 µA

T_J= 25 °C

V_OC

2.05

2.25

2.45

V

T_J= 25 °C

5.40

8.40

3.80

5.70

2.75

4.25

1.75

2.70

6.20

9.70

4.35

6.55

3.15

4.90

2.00

3.10

LYT33x4

I_D= 150 mA

T_J= 100 °Cdrdxd

T_J= 25 °C

LYT33x5

I_D= 200 mA

T_J= 100 °C

ON-State

Resistance

R_DS(ON)

W

T_J= 25 °C

LYT33x6

I_D= 300 mA

T_J= 100 °C

T_J= 25 °C

LYT33x8

I_D= 500 mA

T_J= 100 °C

V_BP= 5.3 V, V_FB> V_FB(SK), V_DS= 580 V

T_J= 125 °C

OFF-State Leakage

Breakdown Voltage

I_DSS

200

µA

V_BP= 5.3 V, V_FB

V_FB(SK)

>

LYT331x

LYT332x

650

725

BV_DSS

V

T_J= 25 °C

NOTES:

A. Guaranteed by design.

12

Rev. D 04/16

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LYT3314-3328

Typical Performance Curves

ꢀ00

1.ꢀ

1

ꢉꢊꢋꢌꢍꢎꢏ ꢐꢋꢊꢑꢒꢓꢔꢕ

ꢅꢆꢇꢃꢃꢀ4 1.0

ꢅꢆꢇꢃꢃꢀꢁ 1.4

ꢅꢆꢇꢃꢃꢀ6 ꢀ.0ꢁ

ꢅꢆꢇꢃꢃꢀꢈ ꢃ.ꢃꢁ

ꢄꢀꢃ ꢅ

6ꢃ0 ꢅ

1ꢂꢁ

1ꢁ0

0.ꢁ

0.6

1ꢀꢁ

100

ꢉꢊꢋꢌꢍꢎꢏ ꢐꢋꢊꢑꢒꢓꢔꢕ

ꢅꢆꢇꢃꢃ14 1.0

ꢅꢆꢇꢃꢃ1ꢁ 1.4

ꢅꢆꢇꢃꢃ16 ꢀ.0ꢁ

ꢅꢆꢇꢃꢃ1ꢈ ꢃ.ꢃꢁ

ꢂꢁ

ꢁ0

ꢀꢁ

0.4

0.ꢀ

0

ꢂꢀꢁ ꢄ

6ꢁ0 ꢄ

0

100 ꢀ00 ꢃ00 400 ꢁ00 600

0

100 ꢀ00 ꢂ00 400 ꢃ00 600 ꢄ00 ꢁ00

ꢀꢁꢂꢃꢄ ꢅꢆꢇꢈꢉꢊꢋ ꢌꢅꢍ

Figure 11. Power vs. Drain Voltage.

Figure 12. Maximum Allowable Drain Current vs. Drain Voltage.

1.ꢀ

1.6

1.4

1.ꢁ

1

ꢀ.ꢀ

ꢀ

1.ꢁ

1.6

1.4

1.ꢀ

1

0.ꢀ

0.ꢁ

0.6

ꢇꢈꢉꢊꢋꢌꢍ ꢎꢉꢈꢏꢐꢑꢒꢓ

0.6

0.4

0.ꢀ

0

ꢇꢈꢉꢊꢋꢌꢍ ꢎꢉꢈꢏꢐꢑꢒꢓ

ꢂꢃꢄꢅꢅ14 1.0

ꢂꢃꢄꢅꢅ1ꢆ 1.4

ꢂꢃꢄꢅꢅ16 ꢀ.0ꢆ

ꢂꢃꢄꢅꢅ1ꢁ ꢅ.ꢅꢆ

ꢔꢁꢆ ꢕ

ꢁꢆ ꢖꢗ

ꢔꢁꢆ ꢕ

1ꢁꢆ ꢖꢗ

6ꢆ0 ꢔ

ꢀꢆ ꢕꢖ

6ꢆ0 ꢔ

1ꢀꢆ ꢕꢖ

0.4

0.ꢁ

0

ꢂꢃꢄꢅꢅꢁ4 1.0

ꢂꢃꢄꢅꢅꢁꢆ 1.4

ꢂꢃꢄꢅꢅꢁ6 ꢁ.0ꢆ

ꢂꢃꢄꢅꢅꢁꢀ ꢅ.ꢅꢆ

0

ꢁ

4

6

ꢀ

10 1ꢁ 14 16 1ꢀ ꢁ0

0

ꢀ

4

6

ꢁ

10 1ꢀ 14 16 1ꢁ ꢀ0

ꢀꢁꢂꢃꢄ ꢅꢆꢇꢈꢉꢊꢋ ꢌꢅꢍ

Figure 13. Drain Current vs. Drain Voltage.

Figure 14. Drain Current vs. Drain Voltage.

10000

1000

100

1

ꢃꢀꢂ ꢄ

6ꢂ0 ꢄ

ꢉꢊꢋꢌꢍꢎꢏ ꢐꢋꢊꢑꢒꢓꢔꢕ

ꢅꢆꢇꢁꢁꢀ4 1.0

ꢅꢆꢇꢁꢁꢀꢂ 1.4

ꢅꢆꢇꢁꢁꢀ6 ꢀ.0ꢂ

ꢅꢆꢇꢁꢁꢀꢈ ꢁ.ꢁꢂ

ꢉꢊꢋꢌꢍꢎꢏ ꢐꢋꢊꢑꢒꢓꢔꢕ

ꢅꢆꢇꢁꢁ14 1.0

ꢅꢆꢇꢁꢁ1ꢂ 1.4

ꢅꢆꢇꢁꢁ16 ꢀ.0ꢂ

ꢅꢆꢇꢁꢁ1ꢈ ꢁ.ꢁꢂ

0

100 ꢀ00 ꢁ00 400 ꢂ00 600

ꢀꢁꢂꢃꢄ ꢅꢆꢇꢈꢉꢊꢋ ꢌꢅꢍ

Figure 15. Drain Capacitance vs. DRAIN Pin Voltage.

13

Rev. D 04/16

www.power.com

LYT3314-3328

ꢀꢁ-1ꢂꢃ

3

4

ꢌꢍꢌ1ꢠ ꢎꢌꢍ48ꢏ

ꢌꢍꢌ13 ꢎꢌꢍ33ꢏ

ꢌꢍꢌꢒꢌ ꢎ1ꢍ2ꢡꢏ

14ꢢ

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8 Lꢄꢅꢞ Tꢇꢤꢚ

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ꢌꢍꢌ1ꢌ ꢎꢌꢍ2ꢒꢏ

1ꢂ

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ꢌꢍ23ꢠ ꢎꢂꢍꢌꢡꢏ

2

ꢕꢅꢖꢉꢄ ꢊꢋꢅꢈꢄ

ꢀꢄꢅꢆꢇꢈꢉ ꢊꢋꢅꢈꢄ

ꢦ

ꢌꢍꢌꢌꢒ ꢎꢌꢍ13ꢏ ꢣ

ꢂ Lꢄꢅꢞ Tꢇꢤꢚ

8

ꢌ

1

8

ꢃ

ꢣ

ꢊꢇꢈ ꢗ1 ꢘꢍꢓꢍ

ꢙLꢅꢚꢄꢛ ꢜꢅꢛꢝꢄꢞꢟ

ꢌꢍꢌ32 ꢎꢌꢍ81ꢏ

ꢌꢍꢌ22 ꢎꢌꢍꢒꢂꢏ

ꢌꢍ13ꢒ ꢎ3ꢍ43ꢏ

ꢐꢄꢑꢍ

2

ꢔ

ꢌꢍ3ꢠꢌ ꢎꢠꢍꢠ1ꢏ

ꢌꢍꢌꢌ4 ꢎꢌꢍ1ꢌꢏ ꢣ ꢔ 2ꢢ

DETAIL A

TOP VIEW

ꢊꢋꢌeꢍꢎ

1. Dꢏꢐeꢑꢍꢏꢋꢑꢏꢑꢒ ꢓꢑꢔ ꢌꢋꢕeꢖꢓꢑꢗꢏꢑꢒ ꢘeꢖ

ꢉꢇꢙꢚ ꢛ14.ꢅꢙꢂ1ꢜꢜ4.

ꢌꢍꢌꢂꢂ ꢎ1ꢍꢂꢠꢏ

ꢌꢍꢌꢒꢡ ꢎ1ꢍ4ꢂꢏ

ꢌꢍꢌꢒ4 ꢎ1ꢍ38ꢏ ꢐꢄꢑꢍ

ꢓꢄꢆꢅꢇꢋ ꢔ

ꢝ. Dꢏꢐeꢑꢍꢏꢋꢑꢍ ꢑꢋꢌeꢔ ꢓꢖe ꢔeꢌeꢖꢐꢏꢑeꢔ ꢓꢌ ꢌꢞe

ꢋꢟꢌeꢖꢐꢋꢍꢌ eꢠꢌꢖeꢐeꢍ ꢋꢡ ꢌꢞe ꢘꢕꢓꢍꢌꢏꢗ ꢢꢋꢔꢣ eꢠꢗꢕꢟꢍꢏve

ꢋꢡ ꢐꢋꢕꢔ ꢡꢕꢓꢍꢞꢤ ꢌꢏe ꢢꢓꢖ ꢢꢟꢖꢖꢍꢤ ꢒꢓꢌe ꢢꢟꢖꢖꢍꢤ ꢓꢑꢔ

ꢏꢑꢌeꢖꢂꢕeꢓꢔ ꢡꢕꢓꢍꢞꢤ ꢢꢟꢌ ꢏꢑꢗꢕꢟꢔꢏꢑꢒ ꢓꢑꢣ ꢐꢏꢍꢐꢓꢌꢗꢞ

ꢢeꢌꢥeeꢑ ꢌꢞe ꢌꢋꢘ ꢓꢑꢔ ꢢꢋꢌꢌꢋꢐ ꢋꢡ ꢌꢞe ꢘꢕꢓꢍꢌꢏꢗ ꢢꢋꢔꢣ.

ꢙꢓꢠꢏꢐꢟꢐ ꢐꢋꢕꢔ ꢘꢖꢋꢌꢖꢟꢍꢏꢋꢑ ꢏꢍ 0.ꢝꢅ ꢐꢐ ꢘeꢖ ꢍꢏꢔe.

ꢀꢄꢅꢆꢇꢈꢉ

ꢊꢋꢅꢈꢄ

ꢌꢍꢌ1ꢌ ꢎꢌꢍ2ꢒꢏ

ꢌꢍꢌꢌ4 ꢎꢌꢍ1ꢌꢏ

ꢄ. Dꢏꢐeꢑꢍꢏꢋꢑꢍ ꢑꢋꢌeꢔ ꢓꢖe ꢏꢑꢗꢕꢟꢍꢏve ꢋꢡ ꢘꢕꢓꢌꢏꢑꢒ

ꢌꢞꢏꢗꢦꢑeꢍꢍ.

ꢣ

ꢌꢍꢌ1ꢌ ꢎꢌꢍ2ꢒꢏ

ꢌꢍꢌꢌ4 ꢎꢌꢍ1ꢌꢏ

ꢌꢍꢌꢌ4 ꢎꢌꢍ1ꢌꢏ ꢣ

14 Lꢄꢅꢞꢚ

4. Dꢋeꢍ ꢑꢋꢌ ꢏꢑꢗꢕꢟꢔe ꢏꢑꢌeꢖꢂꢕeꢓꢔ ꢡꢕꢓꢍꢞ ꢋꢖ ꢘꢖꢋꢌꢖꢟꢍꢏꢋꢑꢍ.

ꢅ. Dꢏꢐeꢑꢍꢏꢋꢑꢍ ꢏꢑ ꢁꢑꢗꢞeꢍ ꢧꢐꢐꢨ.

END VIEW

6. Dꢓꢌꢟꢐꢍ ꢉ ꢓꢑꢔ ꢈ ꢌꢋ ꢢe ꢔeꢌeꢖꢐꢏꢑeꢔ ꢏꢑ Dꢓꢌꢟꢐ ꢩ.

ꢃ. ꢪꢚDꢚꢫ ꢖeꢡeꢖeꢑꢗeꢎ ꢙꢇ − 01ꢝ.

SIDE VIEW

ꢀꢁꢂꢃ4ꢃꢄꢂ061ꢅ1ꢅ

ꢀꢆDꢂꢇꢆꢂ16ꢈ Rev ꢉ

14

Rev. D 04/16

www.power.com

LYT3314-3328

ꢄꢅꢆꢇꢅꢈꢉ ꢊꢅꢋꢇꢌꢍꢈ

ꢀꢁ-1ꢂꢃ

ꢚ

ꢊ

1ꢀ4ꢀ

ꢁꢂꢃꢄꢄꢅꢆD

ꢇ4ꢈ16ꢉꢊ

ꢞ

D

ꢊ. ꢈꢎꢏeꢐ ꢋꢑꢒeꢓꢐꢔꢒꢕꢎꢑꢖ Reꢓꢕꢖꢒeꢐeꢗ ꢃꢐꢔꢗeꢘꢔꢐꢙ

ꢚ. ꢊꢖꢖeꢘꢛꢜꢝ Dꢔꢒe ꢞꢎꢗe ꢟꢜꢔꢖꢒ ꢒꢏꢎ ꢗꢕꢓꢕꢒꢖ ꢎꢠ ꢝeꢔꢐ ꢠꢎꢜꢜꢎꢏeꢗ ꢛꢝ ꢡꢌꢗꢕꢓꢕꢒ ꢏꢎꢐꢙ ꢏeeꢙꢢ

ꢞ. ꢈꢐꢎꢗꢣꢤꢒ ꢋꢗeꢑꢒꢕꢠꢕꢤꢔꢒꢕꢎꢑ ꢟꢈꢔꢐꢒ ꢥ/ꢈꢔꢤꢙꢔꢓe ꢃꢝꢦeꢢ

D. ꢁꢎꢒ ꢋꢗeꢑꢒꢕꢠꢕꢤꢔꢒꢕꢎꢑ ꢞꢎꢗe

ꢈꢋꢌꢉꢆ01ꢌ111ꢍ1ꢀ

15

Rev. D 04/16

www.power.com

LYT3314-3328

MSL Table

Part Number

MSL Rating

LYT33x4

LYT33x5

LYT33x6

LYT33x8

3

ESD and Latch-Up Table

Test

Conditions

JESD78D

Results

Latch-up at 125 °C

Human Body Model ESD

Machine Model ESD

> ±100 mA or > 2.5 kV (max) on all pins

> ±2000 V on all pins

JESD22-A114F

JESD22-A115CA

> ±200 V on all pins

Part Ordering Information

• LYTSwitch-3 Product Family

• Series Number

• Package Identiﬁer

D

SO-16B

• Tape & Reel and Other Options

Blank

Tube of 50 pcs.

TL

Tape & Reel, 2500 pcs min/mult.

LYT 33x4 D - TL

16

Rev. D 04/16

www.power.com

LYT3314-3328

Notes

17

Rev. D 04/16

www.power.com

Revision Notes

Date

A

B

C

D

Code S Release.

09/15

11/09/15

02/16

Added Block diagram and Typical Performance Curves.

Code A Release.

Corrected I_S2parameter. Added V_OCand V_Lparameters.

03/16

T_ON(MAX)parameter errors ﬁxed.

04/01/16

For the latest updates, visit our website: www.power.com

Power Integrations reserves the right to make changes to its products at any time to improve reliability or manufacturability. Power Integrations

does not assume any liability arising from the use of any device or circuit described herein. POWER INTEGRATIONS MAKES NO WARRANTY

HEREIN AND SPECIFICALLY DISCLAIMS ALL WARRANTIES INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT OF THIRD PARTY RIGHTS.

Patent Information

The products and applications illustrated herein (including transformer construction and circuits external to the products) may be covered by one

or more U.S. and foreign patents, or potentially by pending U.S. and foreign patent applications assigned to Power Integrations. A complete list of

Power Integrations patents may be found at www.power.com. Power Integrations grants its customers a license under certain patent rights as set

forth at http://www.power.com/ip.htm.

Life Support Policy

POWER INTEGRATIONS PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS

WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF POWER INTEGRATIONS. As used herein:

1. A Life support device or system is one which, (i) is intended for surgical implant into the body, or (ii) supports or sustains life, and (iii) whose

failure to perform, when properly used in accordance with instructions for use, can be reasonably expected to result in signiﬁcant injury or

death to the user.

2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the

failure of the life support device or system, or to affect its safety or effectiveness.

The PI logo, TOPSwitch, TinySwitch, LinkSwitch, LYTSwitch, InnoSwitch, DPA-Switch, PeakSwitch, CAPZero, SENZero, LinkZero, HiperPFS,

HiperTFS, HiperLCS, Qspeed, EcoSmart, Clampless, E-Shield, Filterfuse, FluxLink, StakFET, PI Expert and PI FACTS are trademarks of Power

Power Integrations Worldwide Sales Support Locations

World Headquarters

5245 Hellyer Avenue

San Jose, CA 95138, USA.

Main: +1-408-414-9200

Customer Service:

Phone: +1-408-414-9665

Fax: +1-408-414-9765

e-mail: usasales@power.com

Germany

Lindwurmstrasse 114

80337 Munich

Japan

Kosei Dai-3 Bldg.

2-12-11, Shin-Yokohama,

Kohoku-ku

Yokohama-shi, Kanagawa

222-0033 Japan

Phone: +81-45-471-1021

Fax: +81-45-471-3717

e-mail: japansales@power.com

Taiwan

5F, No. 318, Nei Hu Rd., Sec. 1

Nei Hu Dist.

Taipei 11493, Taiwan R.O.C.

Phone: +886-2-2659-4570

Fax: +886-2-2659-4550

e-mail: taiwansales@power.com

Germany

Phone: +49-895-527-39110

Fax: +49-895-527-39200

e-mail: eurosales@power.com

India

#1, 14th Main Road

Vasanthanagar

Bangalore-560052 India

Phone: +91-80-4113-8020

Fax: +91-80-4113-8023

e-mail: indiasales@power.com

UK

China (Shanghai)

Rm 2410, Charity Plaza, No. 88

North Caoxi Road

Shanghai, PRC 200030

Phone: +86-21-6354-6323

Fax: +86-21-6354-6325

e-mail: chinasales@power.com

Cambridge Semiconductor,

a Power Integrations company

Westbrook Centre, Block 5, 2nd Floor

Korea

RM 602, 6FL

Korea City Air Terminal B/D, 159-6 Milton Road

Samsung-Dong, Kangnam-Gu,

Seoul, 135-728, Korea

Phone: +82-2-2016-6610

Fax: +82-2-2016-6630

e-mail: koreasales@power.com

Cambridge CB4 1YG

Phone: +44 (0) 1223-446483

e-mail: eurosales@power.com

Italy

China (Shenzhen)

17/F, Hivac Building, No. 2, Keji Nan 20099 Sesto San Giovanni (MI)

Via Milanese 20, 3rd. Fl.

8th Road, Nanshan District,

Shenzhen, China, 518057

Phone: +86-755-8672-8689

Fax: +86-755-8672-8690

e-mail: chinasales@power.com

Italy

Singapore

51 Newton Road

Phone: +39-024-550-8701

Fax: +39-028-928-6009

e-mail: eurosales@power.com

#19-01/05 Goldhill Plaza

Singapore, 308900

Phone: +65-6358-2160

Fax: +65-6358-2015

e-mail: singaporesales@power.com


型号：	LYT3325D
厂家：	Power Integrations
描述：	IC LED DVR DIM 8.8W 1-ST 16SOIC
文件：	总18页 (文件大小：1833K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

LYT3325D [POWERINT]

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