TA9687GN O2MICRO | Alldatasheet

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Technical content

Customer Name : TPV O2 Part Number : ta9687GN R e v i s i o n : A Description : LCDM Inverter Controller Package Type : 16 SOP Lead-Free P a c k T y p e : T u b e Quantity per Type : 48 Quantity per Inner Box : 4,800 Quantity per Ship Box : 28,800 APPROVED BY: Print Name and Signature Date * Please fax back a signed copy to O2 Micro attn: Angela Chang at (03) 564-4273 * Tel : (02) 2545-9095 „ Fax : (02) 2545-9583 (03) 578-7448 „ (03) 578-7897 5F, No.36, Lane162, Keshiueyuan Road, Hsin Chu, Taiwan, 300 APPSHT080131-AC-DS-0.5 01/31/2008 Recipient#115828

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 4/14/2008 ta9687-DS-1.0 - TPV Page 1 Copyright © 2007-2008 by O2Micro All Rights Reserved CONFIDENTIAL 7,120,035; 6,900,993; 6,809,938 and others pending VSEN1 SSTCMP2 CT3 RT14 GNDA5 PDR26 ISEN 14 PWM 13 TIMER 12 VDDA 11 PDR1 10 NDR1 9NDR28 GNDP7 OVPT 15 ENA 16 LCDM Inverter Controller

FEATURES

  • Constant operating frequency
  • Drives positive/negative-impedance lamps during ignition
  • High drive current for external MOSFETs
  • User-defined ignition time and shutdown delay time
  • Built-in intelligence for ignition and normal operation of CCFLs
  • Built-in open-lamp protection and over- voltage protection for backlight system
  • Optimized soft-start function

ORDERING INFORMATION

Part Number Temp Range Package ta9687GN -20oC to +85oC Note(3), page 3 16-pin SOP Lead-Free GENERAL DESCRIPTION ta9687 is a high performance, cost-effective CCFL (Cold Cathode Fluorescent Lamp) controller designed for driving large-size Liquid Crystal Display (LCD) applications requiring 2 to 6 CCFLs. The controller converts unregulated DC voltages into a nearly sinusoidal lamp voltage and current waveforms. The ta9687 supports full-bridge power conversion topologies while maintaining high-efficiency operation. The controller provides a soft-start operation, current and voltage regulation, over- voltage and over-current protection, high drive capability. The control logic provides a regulated ignition voltage and appropriate pr otection features for over-voltage or over-current conditions. The ta9687 offers a high level of integration, while maintaining flexibility and high-efficiency operation that reduces external component heating, resulting in higher reliability and longer CCFL life. The proprietary design technique provides a simple, low-cost system solution. PIN DIAGRAM SIMPLIFIED APPLICATION CIRCUIT VSEN1 SSTCMP2 CT3 RT14 GNDA5 PDR26 ISEN 14 PWM 13 TIMER 12 VDDA 11 PDR1 10 NDR1 9NDR28 GNDP7 OVPT 15 ENA 16 C25 T22 VIN GND PWM VDDA ENA CCFL CCFL CCFL CCFL

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 CONFIDENTIAL ta9687-DS-1.0 Page 2 PIN DESCRIPTION Pin No. I/O Names Description

1 I VSEN Voltage Sense Feedback

2 I/O SSTCMP Capacitor for Soft-Start and Loop Compensation

3 I/O CT Timing Resistor and Capacit or for Operation and Striking Frequency

4 I/O RT1 Timing Resistor for Striking Frequency

6 O PDR2 High Side Driver Output 2

8 O NDR2 Low Side Driver Output 2

9 O NDR1 Low Side Driver Output 1

10 O PDR1 High Side Driver Output 1

11 --- VDDA Input Power Pin

12 I/O TIMER Timing Capacitor for Delay Timer

13 I PWM External PWM Dimming Input

14 I ISEN Current Sense Feedback

15 I OVPT Over-Voltage Protection Threshold Voltage

16 I ENA IC Enable/Disable

I/O1: I=input, O=output, I/O=input/output ABSOLUTE MAXIMUM RATINGS(2) Input Voltage VDDA -0.3V to 7.0V GNDA, GNDP +/- 0.3V All other pins -0.3V to VDDA +0.3V ta9687Operating Temperature3 -20oC to 85oC Operating Junction Temp. 125 oC Storage Temperature3 -55 oC to 150oC RECOMMENDED OPERATING RANGE VDDA - Input Voltage 4.5V to 5.5V Other pins 0V to VDDA fop - Operating Frequency 20KHz to 150KHz Thermal Impedance3,4 θJ-A θJ-C 16-pin SOP 73 oC/W 8 oC/W Note (2): The “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. The device should not be operated at these limits. The “Electrical Characteristics” table defines the conditions for actual device operation. Exposure to absolute maximum rated conditions for extended periods may affect device reliability. Note (3) : Not to exceed the maximum junction temperature of the IC, which relates to the operating power of the IC and the thermal resistance of the IC/package as above Note (4) : Still air, low effective thermal conductivity board per JESD51-3.

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 CONFIDENTIAL ta9687-DS-1.0 Page 3

ELECTRICAL CHARACTERISTICS

All specifications below are at: VDDA=5V; RCT = 84.5KΩ; CCT = 220pF unless otherwise noted. Parameter Symbol Test Conditions Limits Unit Min Typ Max Supply Current Stand By Idds ENA=0V -- 2 5 µA Operating Idd Capacitance at NDR1/2 & PDR1/2 = 1nF 1.6 1.9 2.2 mA Soft Start Current Source ISSTCMP 1.90 2.55 3.20 µA Under Voltage Lockout Lock Out Threshold V UV,TH-OFF VDDA 5V Æ0V 3.2 3.4 3.6 V Resume Threshold V UV,TH-ON VDDA 0V Æ5V 3.3 3.6 4.0 V Reference Voltage ISEN=SSTCMP 1.17 1.23 1.29 V ISEN Reference Voltage Temperature Coefficient 330 ppm/ OC VSEN=SSTCMP 2.75 2.9 3.05 V VSEN Reference Voltage During Striking Temperature Coefficient 340 ppm/ OC Driver Frequency RRT1 = 300K 61.5 63.8 66.0 KHZ Striking f str Temperature Coefficient 200 ppm/ OC 48.0 49.5 51.0 kHz Normal Operation F op Temperature Coefficient 180 ppm/ OC Timer and Protection Striking Current Source ISEN =0V 2.2 3.0 3.8 uA Open Lamp and Over Voltage Protection Current Source SSTCMP > 3.3V or VSEN>OVPT 8.1 10.85 13.6 uA Drivers NDR1/2 Sink R ON_SRC, NDR 2 6 10 Ω NDR1/2 Source R ON_SNK, NDR 10 16 22 Ω PDR1/2 Sink R ON_SRC, PDR 6 12 18 Ω PDR1/2 Source R ON_SNK, PDR 5 9 13 Ω Maximum Overlap ratio 95 -- -- % 100 175 250 ns BBM1&4(PDR_L+NDR_L) 400 ppm/C 100 175 250 ns BBM2&3(PDR_H+NDR_H) 800 ppm/C

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 CONFIDENTIAL ta9687-DS-1.0 Page 4 ELECTRICAL CHARACTERISTICS (Continued) Parameter Symbol Test Conditions Limits Unit Min Typ Max PWM Dimming Control Logic High 2.0 ---- ---- V Logic Low ---- ---- 1.0 V ENABLE Enable Logic V ON 2.0 ---- ---- V Disable Logic V OFF ---- ---- 1.0 V

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 CONFIDENTIAL ta9687-DS-1.0 Page 5 SSTCMP CT +PWM GNDP 2.0V VDDA LO ENA 0.7V and TIMER OVP 1.2V RT1 PDR1 LO OVP NDR1 Lamp ON Ctrl Logic PDR2 ISEN NDR2 HF OSC OLP GNDA 3.0V Driver Logic OVPT LO VDDA Reference Generator VSEN + 3V CLK Protection Ctrl Logic VDDA FUNCTIONAL BLOCK DIAGRAM Figure 1

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 CONFIDENTIAL ta9687-DS-1.0 Page 6 FUNCTIONAL DESCRIPTION 1. Power Conversion The ta9687 controller supports full-bridge power conversion topology and provides symmetrical drive pulses to the tank circuit that includes the transformer(s), output capacitors and the CCFL/panel load that yields quasi-sinusoidal CCFL voltage and current waveforms. High efficiency operation of the ta9687 yields lower heat dissipation for the inve rter system resulting in higher reliability. To illustrate the controller functions, refer to Figures 1 and 2 on pages 5 and 8, respectively for the following sections. 2. Enable Applying a voltage level greater than 2V to ENA (pin 16) enables the IC. A voltage less than 1V will disable the IC. 3. Soft-Start (SST) Utilizing a patented multi-task technique, the soft- start function and the loop compensation function are combined to provide a good start-up characteristic. Connecting an external capacitor to SSTCMP (pin 2) provides the functions. In the start-up mode, current charges capacitor C21 connected to SSTCMP. The voltage at the capacitor controls the gradual increase in power to the transformer and subsequently to the output load. This reduces in-rush current and provides reliable operation to the CCFL. 4. Ignition When the VDDA voltage exceeds the under- voltage lockout threshold, the IC is enabled and internal striking timer is activated. During ignition, the striking frequency for the CCFL(s) can be chosen by the user to optimize the inverter operation. The approximate striking frequency is calculated by the following equation. () ][][//][1 1053.9][ pFCKRCTKRRTKHzF CT STRK ×ΩΩ 5. Aged CCFL Ignition ta9687 provides a striking timer function to ensure that any aged, slow-turn-on CCFL is provided with sufficient voltage and time to ignite. The transformer output voltage is sensed at VSEN (Pin 1). When the voltage at VSEN reaches a threshold of approximately 3.0V, the IC regulates the output volt age at the transformer secondary. If the lamps are not ignited when the voltage at TIMER (pin 12) reaches a threshold of approximately 3V, the IC will shutdown and latch The approximate striking time is calculated by the following equation. ][][ uFCsT TIMERSTRK = To resume normal operation, toggle the ENA signal or reset VDDA. 6. Normal Operation Once the lamps are ignited and the voltage at ISEN (pin 14) is > 0.7V, the IC enters the normal operation mode and the PWM dimming control is activated. The operating frequency is determined by resistor (R15) and capacitor (C22) connected to CT (pin 3). The control loop regulates the average current through the lamps by adjusting the overlap of the out put drives. Constant frequency operation eliminates interference with the inverter and LCD panel that often occurs in a variable frequency inverter system. The peak and valley of the CT waveform are 2V and 0V respectively. The approximate operating frequency is calculated by the following equation. ][][ 1053.9][ pFCKRKHzF CTCT OP 7. Open Lamp Protection If a CCFL is removed or damaged during normal operation, the voltage at SSTCMP (pin 2) rises rapidly because there is no current feedback at ISEN (pin 14). When the voltage at SSTCMP reaches a threshold of approximately 2V and ISEN is less than 0.7V, a current source charges the capacitor (C23) connected to TIMER (pin 12). Once the voltage level at the TIMER pin reaches a threshold of approximately 3V, the drive outputs shut down and latch. The shutdown delay feature avoids inverter shutdown due to a VIN tr ansient or if a lamp has a positive impedance characteristic.

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 CONFIDENTIAL ta9687-DS-1.0 Page 7 The approximate shutdown delay time is calculated by the following equation. ][33.0][ uFCsT TIMERDELAY ×= To resume operation, toggle the ENA signal or restart VDDA. 8. Over-Voltage and Over-Current Protection Over-voltage and over-current protection are monitored by the voltage on VSEN (pin 1). During normal operation, if a CCFL is damaged or removed, the volt age at VSEN increases. Once the voltage at VSEN exceeds the user- defined, preset voltage set by OVPT (pin 15), the driver output duty cycle is regulated and the shutdown delay timer is activated. OVPT sets the overall protection thre shold voltage that is lower than ~3V (VSEN threshold). Once the voltage at TIMR pin reaches ~3V, the IC will shut down and latch. OVPT voltage setting is determined by a resistor divider (R17 and R18) connected to the OVPT. The approximate shutdown delay time is calculated by the following equation. ][33.0][ uFCsT TIMERDELAY ×= To resume operation, toggle the ENA signal or restart VDDA. 9. Dimming Control External PWM dimming is implemented by applying external PWM pulse to PWM (pin 13). When PWM is higher than 2V, dimming is ON and vice versa.

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 CONFIDENTIAL ta9687-DS-1.0 Page 8 REFERENCE APPLICATION CIRCUIT Figure 2: Typical Application VIN: 12V ~ 18V ENA: 0V—1V Disable; 2V—5V Enable VDDA: 4.75V – 5.25V PWM: 3.3Vpp, 200Hz, 10% Min Brightness, 100% Max Brightness R18 100K PDR2 NDR2 C50 4.7u R31 CN2 VIN VIN GND GND ENA PWM PDRA C24 0.1u C63 22p NDR1 C22 220p C65 10p 16VSEN SSTCMP CT RT1 GNDA PDR2 ISEN PWM TIMER VDDA PDR1 NDR1NDR2 GNDP OVPT ENA VS2 ZD1 5.6v 5% R63 D19 DIODE R26 5.1k C38 470u/35V C35 33n AP4502 4 5 C64 2.2n R30 360 CN24 C20 10n VS4 C62 10p AP4502 4 5 C27 0.047u R16 270K C36 0.1u R20 5.1K ENA F1 3A R72 20K 2N3904 ENA R64 4.3K PWM VS1 DIODE R33 R34 100K C21 47n VS4 PWM R67 100K R32 100K VDDA R69 2.2K C39 10u R66 4.3K NDR1 PDR1 ConfidentialCopyright 2007 O2 MicroInc.All Rights ReservedPatent Pending VS3 R71 100K VDDA CN19 R70 2.2K VS2 R65 C26 0.047u R19 5.1K PDRB R68 20K VS3 BAV70/SOT CN22 BAV70/SOT 5.6V NDR2 D17 BAV99/SOT C25 R17 100K T22 VS1 PDRA C66 22p 5.6V R15 84.5K R14 C23 PDRB C67 2.2n D18 DIODE C37 CN23

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 CONFIDENTIAL ta9687-DS-1.0 Page 9 PACKAGE INFORMATION – 16-PIN SOP (150 mil)

Recipient #118203 printed on 4/15/2008. This is a ONE-TIME copy. Updates will not be provided. ta9687 CONFIDENTIAL ta9687-DS-1.0 Page 10 IMPORTANT NOTICE No portion of O2Micro specifications/datasheets or any of its subparts may be reproduced in any form, or by any means, without prior written permission from O2Micro. O2Micro and its subsidiaries reserve the right to make changes to their datasheet s and/or products or to discontinue any product or service without notice, an d advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and c onditions of sale supplied at the time of order acknowledgment, including those pertaining to warranty, patent infringement, and limitation of liability. O2Micro warrants performance of its products to the s pecifications applicable at the time of sale in accordance with O2Micro’s standard warranty. Testing and other quality control techniques are utilized to the extent O2Micro deems necessary to support this warranty. S pecific testing of all parameters of each device is not necessarily performed, except those mandated by government requirements. Customer acknowledges that O 2Micro products are not designed, manufactured or intended for incorporation into any systems or products intended for use in connection with life support or other hazardous activities or environments in which the failure of the O 2Micro products could lead to death, bodily injury, or property or environmental damage (“High Risk Activities”). O2Micro hereby disclaims all warranties, and O2Micro will have no liability to Customer or any third party, relating to the use of O 2Micro products in connection with any High Risk Activities. Any support, assistance, recommendation or inf ormation (collectively, “Support”) that O2Micro may provide to you (including, without limitation, regarding the des ign, development or debugging of your circuit board or other application) is provided “AS IS.” O 2Micro does not make, and hereby disclaims, any warranties regarding any such Support, including, without limitati on, any warranties of merchantability or fitness for a particular purpose, and any warranty that such Support will be accurate or error free or that your circuit board or other application will be operational or functional. O 2Micro will have no liability to you under any legal theory in connection with your use of or reliance on such Support. COPYRIGHT © 2007-2008, O2Micro International Limited