ST VIPER15 User Manual

Features



%5

=&'

'5$,1

*1'

9'')%

6)0%2

'&2XWSXW9ROWDJH









'&,QSXW9ROWDJH

!-V

■ 800 V avalanche rugged power section

■ Quasi-resonant (QR) control for valley

switching operation

■ Standby power < 50 mW at 265 Vac

■ Limiting current with adjustable set point

■ Adjustable and accurate overvoltage

protection

■ On-board soft-start

■ Safe auto-restart after a fault condition

■ Hysteretic thermal shutdown

Applications

■ Adapters for PDA, camcorders, shavers,

cellular phones, cordless phones, videogames

■ Auxiliary power supply for LCD/PDP TV,

monitors, audio systems, computer, industrial
systems, LED driver, No el-cap LED driver,
utility power meter

■ SMPS for set-top boxes, DVD players and

recorders, white goods

VIPER15

Off-line high voltage converters

SO16 narrow

-

Description

The device is an off-line converter with an 800 V
rugged power section, a PWM control, double
levels of overcurrent protection, overvoltage and
overload protections, hysteretic thermal
protection, soft-start and safe auto-restart after
any fault condition removal. Burst mode operation
and device very low consumption helps to meet
the standby energy saving regulations. The quasi­resonant feature reduces EMI filter cost. Brown­out and brown-in function protects the switch
mode power supply when the rectified input
voltage level is below the normal minimum level
specified for the system. The high voltage start-up
circuit is embedded in the device.

Figure 1. Typical topology

DIP-7

Table 1. Device summary

VIPER15HDTR / VIPER15LDTR Tape and reel

August 2010 Doc ID 15455 Rev 5 1/40

Order codes Package Packaging

VIPER15LN / VIPER15HN DIP-7 Tube

VIPER15HD / VIPER15LD

SO16 narrow

Tube

www.st.com

40

Contents VIPER15

Contents

1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2 Typical power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

3 Pin settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

4 Electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

4.1 Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

4.2 Thermal data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

4.3 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

5 Typical electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

6 Typical circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

7 Operation description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

7.1 Power section and gate driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

7.2 High voltage startup generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

7.3 Power-up description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

7.4 Power-down description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

7.5 Auto-restart description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

7.6 Quasi-resonant operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

7.7 Frequency foldback function and valley skipping mode . . . . . . . . . . . . . . 22

7.8 Double blanking time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

7.9 Starter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

7.10 Current limit set point and feed-forward option . . . . . . . . . . . . . . . . . . . . . 24

7.11 Overvoltage protection (OVP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

7.12 Summary on ZCD pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

7.13 Feedback and overload protection (OLP) . . . . . . . . . . . . . . . . . . . . . . . . . 28

7.14 Burst-mode operation at no load or very light load . . . . . . . . . . . . . . . . . . 32

7.15 Brown-out protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

7.16 2nd level overcurrent protection and hiccup mode . . . . . . . . . . . . . . . . . . 34

2/40 Doc ID 15455 Rev 5

VIPER15 Contents

8 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

9 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Doc ID 15455 Rev 5 3/40

Block diagram VIPER15

1 Block diagram

Figure 2. Block diagram

6$$

)

"2

:#$

)

"2

HYST

/60$%4%#4)/.

,/')#

!

6

"2TH

$%-!'

,/

')#





/60

2

,/')#

3/&4

34!24

2

6IN?/+

)NTERNAL3UPPLYBUS

2EFERENCE6OLTAGES

/#0



/3#),,!4/2

34!24%2&2%1#,!-0

,/')#

/#0





07-





"5234-/$%

,/')#

,%"

ND

/#0







"5234

3500,9



56,/

3500,9

"5234

3

2

/40

1

/60

(6?/.

56,/

4(%2-!,

3(54$/7.

/40

3

(6?/.

1

2

6IN?/+

2

$$CH

SENSE

$2

!).

2 Typical power

Table 2. Typical power

Part number

VIPER15 9 W 10 W 5 W 6 W

1. Typical continuous power in non ventilated enclosed adapter measured at 50 °C ambient.

2. Maximum practical continuous power in an open frame design at 50 °C ambient, with adequate heat
sinking.

&"

Adapter

(1)

230 V

AC

Open frame

(2)

Adapter

85-265 V

(1)

'.$

!-V

AC

Open frame

(2)

4/40 Doc ID 15455 Rev 5

VIPER15 Pin settings

3 Pin settings

Figure 3. Connection diagram (top view)

!-V

Note: The copper area for heat dissipation has to be designed under the DRAIN pins.

Table 3. Pin description

Pin n.

Name Function

DIP-7 SO16

1 1...2 GND This pin represents the device ground and the source of the power section.

-4N.A.

25VDD

Not available for user. It can be connected to GND (pins 1-2) or left not
connected.

Supply voltage of the control section. This pin also provides the charging
current of the external capacitor during power-up.

This is a multifunction pin.

1. Input for the zero current detection circuit for transformer demagnetization
sensing. (i.e. R

LIM

, RFF, R

OVP

and D

, Figure 32)

OVP

2. User defined drain current limit set-point and voltage feed forward.The
resistor, R
I

36ZCD

ZCD

3. The resistor R

and then it limits the static maximum drain current.

, connected between ZCD pin and GND causes the current

LIM

, between ZCD pin and the auxiliary winding, performs

FF

the feed-forward operation and then the drain current limitation changes
according to the converter input voltage.

4. Output overvoltage protection. A voltage exceeding V

threshold,

OVP

(see Table 8 on page 8), shuts the IC down reducing the device
consumption. This function is strobed and digitally filtered for high noise
immunity.

Control input for duty cycle control. Internal current generator provides bias

47FB

current for loop regulation. A voltage below the threshold V
the burst-mode operation. A level close to the threshold V

FBbm

means that

FBlin

activates

we are approaching the cycle-by-cycle overcurrent set point.

Brownout protection input with hysteresis. A voltage below the threshold

shuts down (not latch) the device and lowers the power consumption.

V

58BR

BRth

Device operation restarts as the voltage exceeds the threshold V

. It can be connected to ground when not used.

V

BRhyst

BRth

+

High voltage drain pin. The built-in high voltage switched start-up bias

7,8 13...16 DRAIN

current is drawn from this pin too. Pins connected to the metal frame to
facilitate heat dissipation.

Doc ID 15455 Rev 5 5/40

Electrical data VIPER15

4 Electrical data

4.1 Maximum ratings

Table 4. Absolute maximum ratings

Symbol

V

DRAIN

E

AV

I

AR

I

DRAIN

V

ZCD

V

FB

V

BR

V

DD

I

DD

P

TOT

T

J

T

STG

Pin

(DIP7)

Parameter

Val ue

Min. Max.

7, 8 Drain-to-source (ground) voltage 800 V

Repetitive avalanche energy

7, 8

(limited by T

Repetitive avalanche current

7, 8

(limited by T

= 150 °C)

J

= 150 °C)

J

2mJ

1A

7, 8 Pulse drain current (limited by TJ = 150 °C) 2.5 A

3 Control input pin voltage (with I

= 1 mA) -0.3 Self limited V

ZCD

4 Feedback voltage -0.3 5.5 V

5 Brown-out input pin voltage (with IBR = 0.5 mA) -0.3 Self limited V

2 Supply voltage (IDD = 25 mA) -0.3 Self limited V

2 Input current 25 mA

Power dissipation at TA < 40 °C (DIP-7) 1 W

Power dissipation at T

< 60 °C (SO16N) 1 W

A

Operating junction temperature range -40 150 °C

Storage temperature -55 150 °C

Unit

4.2 Thermal data

Table 5. Thermal data

Symbol Parameter

R

R

R

1. When mounted on a standard single side FR4 board with 100 mm2 (0.155 sq in) of Cu (35 μm thick)

6/40 Doc ID 15455 Rev 5

Thermal resistance junction pin

thJP

(Dissipated power = 1 W)

Thermal resistance junction ambient

thJA

(Dissipated power = 1 W)

Thermal resistance junction ambient

thJA

(Dissipated power = 1 W)

(1)

Max. value

SO16N

Max. value

DIP7

35 40 °C/W

90 110 °C/W

80 90 °C/W

Unit

VIPER15 Electrical data

4.3 Electrical characteristics

(TJ = -25 to 125 °C, VDD = 14 V

Table 6. Power section

Symbol Parameter Test condition Min. Typ. Max. Unit

V

BVDSS

I

OFF

R

DS(on)

C

OSS

Table 7. Supply section

Symbol Parameter Test condition Min. Typ. Max. Unit

Break-down voltage

OFF state drain current

Drain-source on state
resistance

Effective (energy related)
output capacitance

(a)

; unless otherwise specified)

I

= 1 mA, VFB = GND

DRAIN

TJ = 25 °C

V

V

I

= max rating,

DRAIN

= GND

FB

= 0.2 A, VFB = 3 V,

DRAIN

VBR = GND, TJ = 25 °C

I

= 0.2 A, VFB = 3 V ,

DRAIN

VBR = GND, TJ = 125 °C

= 0 to 640 V 10 pF

V

DRAIN

800 V

60 μA

20 24 Ω

40 48 Ω

Volt ag e

V

DRAIN

Drain-source start voltage 60 80 100 V

_START

= 120 V,

V

DRAIN

VBR = GND, VFB = GND,

-2 -3 -4 mA

VDD = 4 V

I

DDch

V

DD

V

DDclamp

V

DDon

V

DDoff

V

DD(RESTART)

Start-up charging current

V

= 120 V,

DRAIN

VBR = GND, VFB = GND,

= 4 V after fault.

V

DD

-0.4 -0.6 -0.8 mA

Operating voltage range After turn-on 8.5 23.5 V

VDD clamp voltage IDD = 20 mA 23.5 V

VDD start-up threshold

VDD under voltage
shutdown threshold

VDD restart voltage
threshold

V

V

V

V

= 120 V,

DRAIN

= GND, VFB = GND

BR

= 120 V,

DRAIN

= GND, VFB = GND

BR

13 14 15 V

7.588.5V

44.55 V

Current

I

DD0

I

DD1

I

DD_FAULT

I

DD_OFF

Operating supply current,
not switching

Operating supply current,
switching

Operating supply current,
with protection tripping

Operating supply current
with V

DD

< V

DDoff

VFB = GND, FSW = 0 k H z ,
VBR = GND, VDD = 10 V

V

= 120 V, 2.5 mA

DRAIN

0.9 mA

400 μA

VDD = 7 V 270 μA

a. Adjust VDD above V

start-up threshold before settings to 14 V.

DDon

Doc ID 15455 Rev 5 7/40

Electrical data VIPER15

Table 8. Controller section

Symbol Parameter Test condition Min. Typ. Max. Unit

Feedback pin

V

FBolp

V

FBlin

V

FBbm

V

FBbmhys

I

FB

R

FB(DYN)

H

FB

Overload shutdown threshold 4.5 4.8 5.2 V

Linear dynamics upper limit 3.2 3.3 3.4 V

Burst mode threshold Voltage falling 0.4 0.45 0.5 V

Burst mode hysteresis Voltage rising 50 mV

Feedback sourced current

Dynamic resistance V

ΔVFB / ΔI

ZCD pin

V

ZCDCLh

V

ZCDAth

V

ZCDTth

I

ZCD

T

BLANK

Upper clamp voltage I

Arming voltage threshold Positive-going edge 0.8 V

Triggering voltage threshold Negative-going edge 0.6 V

Internal pull-up -2 µA

Turn-on inhibit time after
MOSFET’s turn-off

Current limitation

I

Dlim

Max drain current limitation

V

= 0.3 V -150 -200 -280 uA

FB

3.3 V < V

FB

D

ZCD

V

ZCD

V

ZCD

< 4.8 V -3 uA

FB

< 3.3 V 14 19 kΩ

26V/A

= 1 mA 5 5.5 6 V

< 1 V 6.3 µs

>1 V 2.5 µs

VFB = 4 V,
I

= -10 µA

ZCD

0.38 0.4 0.42 A

TJ = 25 °C

t

SS

t

SU

T

ON_MIN

Soft start time

Start up time

Minimum turn ON time 220 400 480 ns

td Propagation delay 100 ns

t

LEB

I

D_BM

Overcurrent protection (2

I

DMAX

Overvoltage protection

V

OVP

T

STROBE

Leading edge blanking 300 ns

Peak drain current during
burst mode

nd

OCP)

Second overcurrent threshold 0.6 A

Overvoltage protection
threshold

Overvoltage protection strobe
time

8/40 Doc ID 15455 Rev 5

VIPER15L 3.5 ms

VIPER15H 4.2 ms

VIPER15L 7.5 15 ms

VIPER15H 9.5 18 ms

V

= 0.6 V 90 mA

FB

3.8 4.2 4.6 V

2.2 μs

VIPER15 Electrical data

Table 8. Controller section (continued)

Symbol Parameter Test condition Min. Typ. Max. Unit

Oscillator section

F

OSClim

F

STARTER

F

OSCmin

Internal frequency limit VIPER15H 200 225 250 kHz

Starter frequency

Brown-out protection

Internal frequency limit VIPER15L 122 136 150 kHz

V

BRth

V

BRhyst

I

BRhyst

V

BRclamp

V

DIS

Brown-out threshold Voltage falling 0.41 0.45 0.49 V

Voltage hysteresis above
V

BRth

Current hysteresis 7 12 μA

Clamp voltage IBR = 250 µA 3 V

Brown-out disable voltage 50 150 mV

Thermal shutdown

T

SD

Thermal shutdown
temperature

=1 V,

V

FB

V

ZCD<VZCDT th

t<tSU

VFB=1 V,
V

ZCD<VZCDT th

t>tSU

VFB = 1 V,
V

ZCD>VZCDA_th

1/4

F

OSClim

1/8

F

OSClim

1/64

F

OSClim

kHz

kHz

kHz

Violate rising 50 mV

150 160 °C

T

HYST

Thermal shutdown hysteresis 30 °C

Doc ID 15455 Rev 5 9/40

Electrical data VIPER15

Figure 4. Minimum turn-on time test circuit

V

DRAIN

GND

14 V

3.5 V

VDD

ZCD

FB

DRAIN

DRAIN

50 Ω

BR

30 V

90 %

10 %

I

Dlim

I

DRAIN

T

ONmin

Time

Time

Figure 5. Brown-out threshold test circuits

V

BRth+VBRhyst

V

BRth

V

I

BRhyst

DIS

I

DRAIN

BR

I

BR

Time

Time

14 V

GND

VDD

ZCD

FB

DRAIN

DRAIN

I

BRhyst

BR

10 kΩ

V

30 V

2 V

Note: Adjust V

Figure 6. OVP threshold test circuits

GND

DRAIN

VDD

DRAIN

14 V

above V

DD

start-up threshold before settings to 14 V

DDon

2 V

ZCD

FB

BR

10 kΩ

30 V

Time

V

ZCD

V

OVP

V

DRAIN

Time

Time

10/40 Doc ID 15455 Rev 5

VIPER15 Typical electrical characteristics

5 Typical electrical characteristics

Figure 7. Current limit vs TJ Figure 8. Drain start voltage vs T

J

Figure 9. HFB vs T

Figure 11. Brown-out hysteresis vs T

J

J

Figure 10. Brown-out threshold vs T

J

Figure 12. Brown-out hysteresis current

vs T

J

Doc ID 15455 Rev 5 11/40

Typical electrical characteristics VIPER15

Figure 13. Operating supply current

(no switching) vs T

J

Figure 14. Operating supply current

(switching) vs T

J

Figure 15. V

V

(mV )

ZCD

500

450

400

350

300

0.0 50.0 100.0 150.0 200.0 250.0

ZCD

vs I

I

ZCD

ZCD

(μA)

Figure 17. Power MOSFET on-resistance

vs T

J

Figure 16. Current limit vs I

ZCD

Figure 18. Power MOSFET break down

voltage vs T

J

12/40 Doc ID 15455 Rev 5