Datasheet

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This is information on a product in full production.

August 2013 DocID14419 Rev 9 1/32

VIPER17

Off-line high voltage converters

Datasheet

production data

Figure 1. Typical topology

Features

• 800 V avalanche rugged power section

• PWM operation with frequency jittering for low

EMI

• Operating frequency:

– 60 kHz for L type

– 115 kHz for H type

• 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

• Hysteresis thermal shutdown

Application

• Adapters for PDA, camcorders, shavers,

cellular phones, videogames

• Auxiliary power supply for LCD/PDP TV,

monitors, audio systems, computer, industrial

systems, LED driver, No el-cap LED driver

• SMPS for set-top boxes, DVD players and

recorders, white goods

Description

The device is an off-line converter with an 800 V

rugged power section, a PWM control, two levels

of overcurrent protection, overvoltage and

overload protections, hysteresis thermal

protection, soft-start and safe auto-restart after

any fault condition removal. The burst mode

operation and the device’s very low consumption

meet the standby energy saving regulations.

Advance frequency jittering reduces EMI filter

cost. Brown-out 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.

DIP-7

SO16 narrow

DC input high voltage

wide range

DC Output voltage

VIPER17

DRAIN

VDD

CONT

GND

Table 1. Device summary

Order codes Package Packaging

VIPER17LN / VIPER17HN DIP-7 Tube

VIPER17HD / VIPER17LD

SO16 narrow

Tube

VIPER17HDTR / VIPER17LDTR Tape and reel

www.st.com

Summary of content (32 pages)

PAGE 1
VIPER17 Off-line high voltage converters Datasheet - production data • On-board soft-start • Safe auto-restart after a fault condition • Hysteresis thermal shutdown SO16 narrow SO-16 Application DIP-7 • Adapters for PDA, camcorders, shavers, cellular phones, videogames Figure 1.
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Contents VIPER17 Contents 1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2 Typical power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3 Pin settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4 Electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4.1 Maximum ratings . . . . .
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VIPER17 1 Block diagram Block diagram Figure 2. Block diagram VDD Vcc BR DRAIN + Vin_OK VBRth Internal Supply bus & Ref erence Voltages SUPPLY & UVLO HV_ON I DDch 15uA UVLO - CONT OCP BLOCK OTP OCP BURST + SOFT START . OVP LOGIC + THERMAL SHUTDOWN OSCILLATOR PWM TURN-ON LOGIC LEB S Q R1 R2 6uA + OVP 2nd OCP LOGIC Ref OLP OVP OTP Rsense BURST-MODE LOGIC BURST FB 2 GND Typical power Table 2.
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Pin settings 3 VIPER17 Pin settings Figure 3. Connection diagram (top view) '5$,1 '5$,1 '5$,1 '5$,1 $0 Y 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. - 4 N.A. Not available for user. It can be connected to GND (pins 1-2) or left not connected. 2 5 VDD Supply voltage of the control section.
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VIPER17 Electrical data 4 Electrical data 4.1 Maximum ratings Table 4. Absolute maximum ratings Symbol Value Pin (DIP7) Parameter Unit Min VDRAIN 7, 8 Drain-to-source (ground) voltage EAV 7, 8 IAR Max 800 V Repetitive avalanche energy (limited by TJ = 150 °C) 2 mJ 7, 8 Repetitive avalanche current (limited by TJ = 150 °C) 1 A IDRAIN 7, 8 Pulse drain current 2.5 A VCONT 3 Control input pin voltage (with ICONT = 1 mA) -0.3 Self limited V VFB 4 Feed-back voltage -0.3 5.
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Electrical data 4.3 VIPER17 Electrical characteristics (TJ = -25 to 125 °C, VDD = 14 V(a); unless otherwise specified) Table 6. Power section Symbol VBVDSS IOFF RDS(on) COSS Parameter Test condition Break-down voltage IDRAIN = 1 mA, VFB = GND TJ = 25 °C OFF state drain current VDRAIN = max rating, Min Typ Max Unit 800 V 60 μA VFB = GND IDRAIN = 0.2 A, VFB = 3 V, VBR = GND, TJ = 25 °C 20 24 Ω IDRAIN = 0.
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VIPER17 Electrical data Table 7. Supply section (continued) Symbol IDD_FAULT IDD_OFF Parameter Test condition Min Typ Max Unit Operating supply current, with protection tripping Operating supply current with VDD < VDD_off VDD = 7 V 400 μA 270 μA Table 8. Controller section Symbol Parameter Test condition Min Typ Max Unit Feed-back pin VFBolp Overload shut down threshold 4.5 4.8 5.2 V VFBlin Linear dynamics upper limit 3.2 3.3 3.
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Electrical data VIPER17 Table 9. Controller section (continued) Symbol Parameter Test condition Min Typ Max Unit Overcurrent protection (2nd OCP) IDMAX Second over current threshold 0.6 A Overvoltage protection VOVP TSTROBE Overvoltage protection threshold 2.7 Overvoltage protection strobe time 3 3.3 V 2.2 μs Brown out protection VBRth Brown out threshold Voltage falling 0.41 0.45 0.
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VIPER17 Electrical data Figure 4. Minimum turn-on time test circuit VDRAIN 14 V GND DRAIN VDD DRAIN 90 % TONmin 50 Ω CONT 10 % IDRAIN BR FB 30 V 3.5 V Time IDLIM Time Figure 5. Brown out threshold test circuit VBR GND DRAIN VBRth+VBRhyst VBRth VDD DRAIN VDIS IBR Time IDRAIN Time 10 kΩ CONT IBRhyst IBRhyst BR FB 14 V 30 V 2V Time Figure 6.
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Typical electrical characteristics 5 10/32 VIPER17 Typical electrical characteristics Figure 7. Current limit vs TJ Figure 8. Switching frequency vs TJ Figure 9. Drain start voltage vs TJ Figure 10. HFB vs TJ Figure 11. Brown out threshold vs TJ Figure 12.
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VIPER17 Typical electrical characteristics Figure 13. Brown out hysteresis current vs TJ Figure 14. Operating supply current (no switching) vs TJ Figure 15. Operating supply current (switching) vs TJ Figure 16. current limit vs RLIM Figure 17. Power MOSFET on-resistance vs TJ Figure 18.
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Typical electrical characteristics VIPER17 Figure 19.
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VIPER17 6 Typical circuit Typical circuit Figure 20. Min-features flyback application D3 Vout R1 AC IN C2 BR C1 C5 AC IN D1 GND D2 R2 R3 OPTO VVcc DD DRAIN R5 BR CONTROL C3 R4 C6 CONT FB GND SOURCE U2 C4 R6 Figure 21.
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Operation descriptions 7 VIPER17 Operation descriptions VIPER17 is a high-performance low-voltage PWM controller chip with an 800 V, avalanche rugged power section. The controller includes: the oscillator with jittering feature, the start up circuits with soft-start feature, the PWM logic, the current limit circuit with adjustable set point, the second over current circuit, the burst mode management, the brown-out circuit, the UVLO circuit, the auto-restart circuit and the thermal protection circuit.
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VIPER17 Operation descriptions CVDD capacitor must be sized enough to avoid fast discharge and keep the needed voltage value higher than VDDoff threshold. In fact, a too low capacitance value could terminate the switching operation before the controller receives any energy from the auxiliary winding.
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Operation descriptions VIPER17 Figure 23. Timing diagram: normal power-up and power-down sequences VIN VIN < VDRAIN_START HV startup is no more activated VDRAIN_START VDD regulation is lost here time VDDon VDDoff VDD(RESTART) VDRAIN time IDD time IDDch (3mA) time Power-off Normal operation Power-on Figure 24.
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VIPER17 7.4 Operation descriptions Power down operation At converter power down, the system loses regulation as soon as the input voltage is so low that the peak current limitation is reached. The VDD voltage drops and when it falls below the VDDoff threshold (see Table 7 on page 6) the power MOSFET is switched OFF, the energy transfers to the IC interrupted and consequently the VDD voltages decreases, Figure 23 on page 16.
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Operation descriptions 7.6 VIPER17 Oscillator The switching frequency is internally fixed to 60 kHz or 115 kHz. In both case the switching frequency is modulated by approximately ±4 kHz (60 kHz version) or ±8 kHz (115 kHz version) at 250 Hz (typical) rate, so that the resulting spread-spectrum action distributes the energy of each harmonic of the switching frequency over a number of sideband harmonics having the same energy on the whole but smaller amplitudes. 7.
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VIPER17 Operation descriptions Equation 2 V OVP k OVP = --------------------------------------------------------------------------------------------------N AUX -------------- ⋅ ( V OUTOVP + V DSEC ) – V DAUX N SEC Equation 3 R LIM k OVP = ---------------------------------R LIM + R OVP Where: • VOVP is the OVP threshold (see Table 9 on page 8) • VOUT OVP is the converter output voltage value to activate the OVP (set by designer) • NAUX is the auxiliary winding turns • NSEC is the secondary windin
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Operation descriptions VIPER17 Figure 26. OVP timing diagram t VAUX 0 VCONT t V OVP t 2 µs STROBE 0.5 µs t OVP t COUNTER RESET COUNTER STATUS t 0 0 0 →1 0 1 →2 2 →0 0 0 →1 2 →3 1 →2 3 →4 FAULT t NORMAL OPERATION 7.9 TEMPORARY DISTURBANCE t FEEDBACK LOOP FAILURE About CONT pin Referring to the Figure 27, through the CONT pin, the below features can be implemented: 1. Current Limit set point 2.
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VIPER17 Operation descriptions Table 10. CONT pin configurations Function / component RLIM (1) ROVP DAUX IDlim reduction See Figure 16 No No OVP ≥ 80 KΩ See Equation 4 Yes IDlim reduction + OVP See Figure 16 See Equation 4 Yes 1. RLIM has to be fixed before of ROVP 7.10 Feed-back and overload protection (OLP) The VIPER17 is a current mode converter: the feedback pin controls the PWM operation, controls the burst mode and actives the overload protection.
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Operation descriptions VIPER17 After the start up time, tSS, during which the feedback voltage is fixed at VFBlin, the output capacitor could not be at its nominal value and the controller interpreter this situation as an over load condition. In this case, the OLP delay helps to avoid an incorrect device shut down during the start up.
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VIPER17 Operation descriptions Figure 28. FB pin configuration From sense FET PWM To PWM Logic + PWM CONTROL - Cfb BURST BURST-MODE LOGIC BURST-MODE References OLP comparator To disable logic + VFBolp - Figure 29. FB pin configuration From RSENSE PWM To GATE driver + PWM CONTROL - Rfb1 Cfb BURST Cfb1 BURST-MODE References BURST-MODE LOGIC OLP comparator + VFBolp 7.
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Operation descriptions VIPER17 Figure 30. Burst mode timing diagram, light load management VFB 100 50 mV hyster. VFBbm t IDRAIN Normal -mode 7.12 Burst-mode Normal -mode t Brown-out protection Brown-out protection is a not-latched shutdown function activated when a condition of mains under voltage is detected. The Brown-out comparator is internally referenced to VBRth threshold, see Table 8 on page 7, and disables the PWM if the voltage applied at the BR pin is below this internal reference.
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VIPER17 Operation descriptions Figure 31.
PAGE 26
Operation descriptions 7.13 VIPER17 2nd level overcurrent protection and hiccup mode The VIPER17 is protected against short circuit of the secondary rectifier, short circuit on the secondary winding or a hard-saturation of fly-back transformer. Such as anomalous condition is invoked when the drain current exceed the threshold IDMAX (see Table 8 on page 7). To distinguish a real malfunction from a disturbance (e.g. induced during ESD tests) a “warning state” is entered after the first signal trip.
PAGE 27
VIPER17 8 Package mechanical data Package mechanical data In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK® packages, depending on their level of environmental compliance. ECOPACK® specifications, grade definitions and product status are available at: www.st.com. ECOPACK® is an ST trademark. Table 11. DIP-7 mechanical data mm Dim.
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Package mechanical data VIPER17 Figure 33.
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VIPER17 Package mechanical data Table 12. SO16 narrow mechanical data Dimensions Databook (mm.) Ref. Min Typ. A Max 1.75 A1 0.1 A2 1.25 b 0.31 0.51 c 0.17 0.25 D 9.8 9.9 10 E 5.8 6 6.2 E1 3.8 3.9 4 e 0.25 1.27 h 0.25 0.5 L 0.4 1.27 k 0 8 ccc 0.
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Package mechanical data VIPER17 Figure 34.
PAGE 31
VIPER17 9 Revision history Revision history Table 13. Document revision history Date Revision Changes 14-Feb-2008 1 Initial release 19-Feb-2008 2 Updated: Figure 1 on page 1, Figure 3 on page 4 21-Jul-2008 3 Added new SO16 package 30-Sep-2008 4 Updated Equation 9, Equation 10 16-Jan-2009 5 Updated Chapter 7.
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VIPER17 Please Read Carefully: Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale.