UBA2071AT NXP [NXP Semiconductors], UBA2071AT Datasheet
UBA2071AT
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UBA2071AT Summary of contents
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UBA2071; UBA2071A Half bridge control IC for CCFL backlighting Rev. 01 — 23 June 2008 1. General description The UBA2071 and UBA2071A are high voltage ICs intended to drive Cold Cathode Fluorescent Lamps (CCFLs) or External Electrode Fluorescent Lamps (EEFLs) ...
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... UBA2071_A_1 Product data sheet Quick reference data VDD IREF Parameter Conditions voltage on pin SH voltage on pin VDD current on pin VDD EN pin grounded; V VDD UBA2071AT and UBA2071ATS oscillating disabled; V VDD oscillating 100 pF; GL and GH open PWMD V ...
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... PWMD is during each cycle low and the lamps are the time on, resulting in a light output Ordering information Table 2. Ordering information Type number Package Name UBA2071T SO24 UBA2071AT SO24 UBA2071TS SSOP24 UBA2071ATS SSOP24 UBA2071_A_1 Product data sheet Quick reference data VDD IREF EN Parameter Conditions overvoltage threshold voltage on ...
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NXP Semiconductors 6. Block diagram INTERNAL IREF SUPPLY VDD AND REFERENCE SGND CIRCUITS OSCILLATOR CSWP TRACK AND CVFB SWEEP OVER- VFB VOLTAGE SENSING ARCING DETECTION OVER- CURRENT DETECTION DOUBLE LAMP IFB SIDE CURRENT RECTIFIER SENSING Fig 1. ...
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NXP Semiconductors 7. Pinning information 7.1 Pinning Fig 2. 7.2 Pin description Table 3. Pin description Symbol Pin Description IFB 1 current feedback input. CIFB 2 current regulation capacitor. VFB 3 voltage feedback input CVFB 4 voltage regulation capacitor CSWP ...
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NXP Semiconductors Table 3. Pin description …continued Symbol Pin Description NONFAULT 12 status signal input/output PWMD 13 digital PWM dimming input/output PWMA 14 analog PWM dimming input EN 15 chip enable input VDD 16 supply input PGND 17 power ground ...
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NXP Semiconductors Fig 3. 8.1 Supply, Start-up and UnderVoltage LockOut (UVLO) Fig 4. The UBA2071 is supplied via the VDD pin as shown in either made by the inverter itself, using auxiliary fixed supply ...
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NXP Semiconductors 8.2 V clamp DD When the UBA2071 is disabled (EN pin low the stop state, the V activated. The V prevents the start-up current source from charging the V voltage. The maximum current that is allowed ...
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NXP Semiconductors Fig 5. 8.5 Non-overlap During each transition between the two states GL high/GH low and GL low/GH high, GL and GH will both be low for a fixed time charged or discharged by the load ...
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NXP Semiconductors When the voltage on the EN pin goes over V pin below V the voltage on the EN pin goes over V V th(L)(EN) mode. When the voltage on the EN pin goes over V initial ignition frequency ...
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NXP Semiconductors (H)2(EN) EN (H)1(EN) (L)(EN Fig 7. Remark: Due to the nature of the charging sequence, V charged to 0.5 charging mode longer than necessary, V constant made by R1 and C1 in example ...
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NXP Semiconductors (1) Indicates lamp-OFF. (2) Indicates lamp-ON. Fig 8. Advantage of the sweep rather than a fixed ignition frequency is that sensitivity for spread in resonance frequency is much lower. Once the lamps are ignited the frequency sweep-down continues, ...
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NXP Semiconductors Fig 9. The lamps start switching again on period GL and GH and the frequency is swept back to the regulation frequency f proportional to the capacitor connected to the CSWP pin. 8.9 Overvoltage control The overvoltage control ...
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NXP Semiconductors When the voltage on the VFB pin exceeds V handling of fault conditions, see changed to the discharge current I and the output voltage of the transformer will decrease VFB pin drops below V voltage of the transformer ...
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NXP Semiconductors to CCFLs Fig 11. Lamp frequency control circuit Under normal operating conditions, the voltage across capacitor C2, which is connected to the CVFB pin, will follow the voltage on the CIFB pin. During the lamps-on period of the ...
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NXP Semiconductors PWM lamp-on situation is reached again through a reverse sequence of events, starting the half bridge actions, increasing the voltage on CSWP, increasing the lamp current back to the controlled value. Switch S1 is closed (conducting) again when ...
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NXP Semiconductors Fig 13. PWM dimming configurations When the CPWM pin is connected to ground the IC is put in digital or slave mode and the PWMD pin is an input. The internal PWM generator is not used. The IC ...
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NXP Semiconductors Fig 14. Fault timer waveforms If the fault timer is inactive, the CT pin voltage is 1 Vbe, about 0.7 V. The CT timer has a protection that prevents the IC to start up if the CT pin ...
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NXP Semiconductors • OverCurrent Protection (OCP), • bad contact or ARCing (ARC), • Ignition Failure (IF), • open or shorted current feedback (IFB pin open/short), • open or shorted voltage feedback (VFB pin open/short) • Hard Switching (HS). There are ...
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NXP Semiconductors 8.14.2 Overvoltage protection The overvoltage control, see voltage from exceeding its maximum rating. The overvoltage control level has least at the required lamp ignition voltage, otherwise the lamps may not ignite. Once the lamps are ...
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NXP Semiconductors times in case overvoltage and overvoltage extra are detected at the same moment (curve (1)) and if overvoltage, overvoltage extra and hard switching are detected at the same moment (curve (2)). The first parts of the curves are ...
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NXP Semiconductors duration longer than t the control circuits that arcing has been detected. When arcing is detected, PWM dimming is disabled and the fault timer is started. 8.14.8 Ignition Failure (IF) When the current control loop comes close to ...
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NXP Semiconductors The signal from the voltage signal and the signal to the current signal. In this way a driving conflict is prevented. Also, it leaves the possibility for the outside world to see ...
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... CPWM connected to a capacitor, unless otherwise specified. All EN VDD Conditions and VDD UBA2071T and UBA2071TS UBA2071AT and UBA2071ATS UBA2071T and UBA2071TS UBA2071AT and UBA2071ATS pin grounded VDD Rev. 01 — 23 June 2008 UBA2071; UBA2071A Half bridge control IC for CCFL backlighting Min 0.1 0.1 0 ...
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... Product data sheet = and CPWM connected to a capacitor, unless otherwise specified. All EN VDD Conditions EN pin grounded; I UBA2071T and UBA2071TS EN pin grounded; I UBA2071T and UBA2071TS EN pin grounded; V UBA2071AT and UBA2071ATS VFB CVFB(max) oscillating at f sw(min 100 pF CF disabled; V VDD oscillating ...
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NXP Semiconductors Table 6. Characteristics …continued amb VDD IREF voltages are measured with respect to signal ground (SGND, pin 10). SGND and PGND connected together. GL, GH, COMM, NONFAULT and PWMD ...
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NXP Semiconductors Table 6. Characteristics …continued amb VDD IREF voltages are measured with respect to signal ground (SGND, pin 10). SGND and PGND connected together. GL, GH, COMM, NONFAULT and PWMD ...
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NXP Semiconductors 12. Application information Figure 19 from a high voltage DC source and the IC is supplied by means supply (C14, C15, Z1 and D1). Two lamps are connected, each to the output of its ...
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R2 HVDC NONFAULT C2 VDD GND CN1 PWMA CIFB C4 PWMD CVFB CSWP R1 IREF SGND C8 CPWM PWMA PWMD COMM (1) Optional lamp short protection is available via the NONFAULT pin. ...
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HVsupply UBA2071 VDD IREF CF CT CSWP CVFB CIFB CPWM SGND PWMA PWMA enable EN PWMD PWMD Fig 20. Example of balanced backlighting application PGND IFB VFB COMM NONFAULT UBA2073 GH VDD COMM ...
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NXP Semiconductors 13. Package outline SO24: plastic small outline package; 24 leads; body width 7 pin 1 index 1 e DIMENSIONS (inch dimensions are derived from the original mm dimensions) A UNIT ...
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NXP Semiconductors SSOP24: plastic shrink small outline package; 24 leads; body width 5 pin 1 index 1 e DIMENSIONS (mm are the original dimensions) A UNIT max. 0.21 1.80 mm ...
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NXP Semiconductors 14. Revision history Table 7. Revision history Document ID Release date UBA2071_A_1 20080623 UBA2071_A_1 Product data sheet Half bridge control IC for CCFL backlighting Data sheet status Change notice Product data sheet - Rev. 01 — 23 June ...
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NXP Semiconductors 15. Legal information 15.1 Data sheet status [1][2] Document status Product status Objective [short] data sheet Development Preliminary [short] data sheet Qualification Product [short] data sheet Production [1] Please consult the most recently issued document before initiating or ...
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NXP Semiconductors 17. Contents 1 General description . . . . . . . . . . . . . . . . . . . . . . 1 2 Features . . . . . . . . ...