ATAVRFBKIT Atmel, ATAVRFBKIT Datasheet
ATAVRFBKIT
Specifications of ATAVRFBKIT
Related parts for ATAVRFBKIT
ATAVRFBKIT Summary of contents
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... ATAVRFBKIT / EVLB001 Dimmable Fluorescent Ballast ............................................................................................................................... User Guide ...
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... ATAVRFBKIT / EVLB001 User Guide Section 1 Introduction ........................................................................................... 1-1 1.1 General Description ..................................................................................1-3 1.2 Ballast Demonstrator Features .................................................................1-3 Section 2 Ballast Demonstrator Device Features ................................................. 2-4 2.1 Atmel Supported Products ........................................................................2-4 ® 2.2 IXYS Supported Products .......................................................................2-4 Section 3 Microcontroller Port Pin Assignments ................................................... 3-6 Section 4 Ballast Demonstrator Operation ........................................................... 4-7 4 ...
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... ATAVRFBKIT / EVLB001 User Guide Efficient fluorescent lamps and magnetic ballasts have been the standard lighting fixture in commercial and industrial lighting for many years. Several lamp types, rapid start, high output, and others are available for cost effective and special applications. But incandescent lamps, in spite of the poor light to power ratio, typically one fourth of fluo- rescent, offer one feature - dimming - that hasn’ ...
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... ATAVRFBKIT / EVLB001 User Guide Figure 1-1. Fluorescent Tube Composition Since the argon conductivity increases and resistance across the lamp ends decreases as the gas becomes excited, an inductance (ballast) must be used to limit and control the gas current. In the past, an inductor could be designed to limit the current for a nar- row range of power voltage and frequency. A better method to control gas current is to vary an inductor’ ...
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... Power feedback for stable operation over line voltage range • Variable frequency half bridge inverter • 18W type T8 lamps • Automatic dimmable single lamp operation • Automatic detection of Swiss or DALI • Very versatile power saving options with microcontroller design for most functions ATAVRFBKIT / EVLB001 User Guide ...
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... IXYS Supported Products ATAVRFBKIT / EVLB001 User Guide Ballast Demonstrator Device Features AT90PWM2B/216 Microcontroller • High speed comparator for PFC zero crossover detection • 6 Analog inputs for A/D conversion, 2.56V reference level • 3 Digital inputs used for the dimming control input • ...
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... TXD/DALI/PD3 DALI_RX RXD/DALI/PD4 SWITCH_CTRL ADC7/PB6 V_LAMP ADC3/PD6 Inverter High PSCOUT20/PB0 I_LAMP AMP0+/PB4 Inverter Low PSCOUT21/PB1 AMP0-/PB3 RESONATING INDUCTOR TRANSFORMER AND FILAMENT INVERTER TRANSFORMER 15V IXD611 10 5 Driver C11 7 C14 Driver R28 ATAVRFBKIT / EVLB001 User Guide BALANCE AND LAMPS R42 ...
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... ATAVRFBKIT / EVLB001 User Guide Microcontroller Port Pin Assignments PD0 PCOUT00 PFC_OUTPUT - To IXI859 FET driver input PD1 PSCIN0 DUAL_LAMP - Dual lamp detection PD3 TXD/DALI DALI_TX - DALI transmit line PD4 RXD/DALI DALI_RX - DALI receive line PD5 ADC2 LAMP_EOL - Not supported in hardware nor software ...
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... General Requirements 4.2 Startup features ATAVRFBKIT / EVLB001 User Guide Ballast Demonstrator Operation Constant power as determined by DALI or Switch Control • 400 volt DC bus as provided by a power factor correcting boost regulator (PFC) 100 dimming setting One or two lamps, type T8 of 18W • ...
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... Circuit Topology 4.4 Startup and PFC Description ATAVRFBKIT / EVLB001 User Guide Input filter with varistor for noise suppression and protection. PFC / boost circuit including IXI859 MOSFET driver AT90PWM2B/216 microcontroller 24 pin SOIC half bridge driver half bridge power MOSFET stage for lamps ...
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... After PD7 comparator transition and 400VDC (2.368V at PB2), enable PFC control loop. -Adjust PB2 (400VDC sense) setpoint to 2.368V with deadband. -If PB2 > 2.50V then inhibit PD0 pulse. -If PB2 = < 2.368V then use the control loop to establish the PD0 PFC pulse width. ATAVRFBKIT / EVLB001 User Guide ...
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... Lamp Operation Description 4.5.1 Single Lamp Operation ATAVRFBKIT / EVLB001 User Guide Limit pulse width to 25uS or as determined by the haversine peak voltage. The adjustment of the PFC T and The T is automatically adjusted by hardware at each PFC inductor current zero OFF crossing detection, - The T ...
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... If Switch control, proceed to max power. A continuous pressing of this switch will cause a progressive increase of frequency at 33 kHz per second. The exception for a single lamp will be minimum frequency for 97mV (39 watts) at PB4 for 100% brightness. This is the default power for a single lamp with no dimming. ATAVRFBKIT / EVLB001 User Guide ...
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... Power Control Description ATAVRFBKIT / EVLB001 User Guide Calculate input power for both lamps = PB4 (lamp current) * (lamp voltage). Use this data for DALI feedback verification if required. Set programmable gain of AMP0 to 10. 78 watts will be 0.195 VDC at the input of AMP0+ or 1.95V internal A/D input. ...
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... USED AS CURRENT SOURCE 5.3 IXYS IXD611 Half- bridge MOSFET driver ATAVRFBKIT / EVLB001 User Guide Device Design & Application PFC – Power Factor Correction Without going into the derivations of the formulae used, the inductor design is as follows 1.4 * 90VAC * 25 µ 4.5A peak The ON time has been discussed earlier and the OFF time maximum will occur at high line condition at the peak of the haversine ...
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... IXYS IXI859 Charge Pump Regulator ATAVRFBKIT / EVLB001 User Guide Other features of the IXD611 driver include: Wide supply voltage operation 10-35V Matched propagation delay for both drivers Undervoltage lockout protection Latch up protected over entire operating range +/- 50V/ns dV/dt immunity The IXI859 charge pump regulator integrates three primary functions central to the PFC stage of the ballast demonstrator ...
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... While both AC and DC input versions are avail- able, the LDA111S input only model and features a rating, 3750V input to output isolation, and a 1000% current transfer ratio. RMS The LDA111S role is to isolate control signals within the ballast design. 100mA continuous load ATAVRFBKIT / EVLB001 User Guide ...
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... ATAVRFBKIT / EVLB001 User Guide ATPWMX Demonstrator Software This section of the application note describes the software architecture utilizing the fol- lowing source code files and related state machines: Main_fbkit.c Initialisation of peripherals (Ports, ADC, timer...). Clock pfc and lamp task each 200uS and let control task operating during free time. ...
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... Voltage and current variables are identified by the following examples. g_v or g_i global - voltage/current gv_v or gv_i global volatile - voltage/current gs_v or gs_i global static - voltage/current Analog comparator gv_v_haversine gv_v_bus COMMAND CTRL gv_pfc_state DALI gv_lamp_on gv_lamp_preset _current gv_lamp_state gv_i_lamp gv_v_lamp PFC CTRL PFC_OUTPUT LAMP CTRL INVERTER_HIGH INVERTER_LOW ATAVRFBKIT / EVLB001 User Guide ...
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... ATAVRFBKIT / EVLB001 User Guide This file executes all the peripheral initialization and then schedules the different control tasks. The ADC and the Command control state machines are also included in this file. The ADC machine is controlled via interrupts. ...
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... INIT_PFC_HAVERSINE_CHECK Initialize the control values of the PFC. Then jump to the HAVERSINE_CHECK state. HAVERSINE_MEASURE Measure the haversine peak voltage during HAVERSINE_MIN_CHECK_TIME. Then jump to the HAVERSINE_CHECK state. values, gv_lamp_state, can be set to the following values gv_lamp_preset_current ATAVRFBKIT / EVLB001 User Guide ...
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... PFC_PROBLEM PFC_DELAY_FOR_NEXT_SOFT_START SHUT_DOWN_PFC_AND_SLOW_DOWN_UC_SPEED ATAVRFBKIT / EVLB001 User Guide PFC_OFF gv_lamp_preset_current != 0 during control_task in control_FBKIT.c INIT_PFC INIT_PFC_HAVERSINE_CHECK HAVERSINE_MEASURE g_pfc_time_since_previous_timer_reset <= HAVERSINE_CHECK HAVERSINE_PEAK_MIN <= gs_v_haversine_peak <= (0.95 * gs_v_haversine_peak) <= gv_v_bus <= V_BUS_SET_POINT CONFIGURE_PFC_SOFT_START PFC_SOFT_START gs_pfc_soft_start_tries <= PFC_START_MAX_TRIES SPEED_UP_MICROCONTROLLER Get_v_bus() <= V_BUS_OVERSHOOT gvs_zcd_occures PFC_FIND_ZCD gvs_zcd_occures == 1 PFC_CONTROL_LOOP gv_lamp_preset_current == 0 during control_task in control_FBKIT.c HAVERSINE_CHECK PFC haversine peak must be between HAVERSINE_PEAK_MIN and HAVERSINE_ PEAK_MAX (90VAC and 265VAC) ...
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... CONFIGURE_PFC_SOFT_START state. PFC_FIND_ZCD Find the Zero Crossing Detection in order to start the PFC_CONTROL_LOOP on a zero crossing. SHUT_DOWN_PFC_AND_SLOW_DOWN_UC_SPEED Switch off the PFC. Switch the microcontroller to a low power consumption mode. Then go back to PFC_OFF state. ATAVRFBKIT / EVLB001 User Guide ...
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... Lamp State Machine Figure 6-4. Lamp State Machine gv_lamp_preset_current == 0 during control_task in control_FBKIT.c TOO_MANY_LAMP_IGNITION_TRIES RESTART_PREHEAT ATAVRFBKIT / EVLB001 User Guide • gv_lamp_preset_current which is modified in control_FBKIT.c file makes the PFC state machine changing from PFC_OFF to INIT_PFC when the user request to switch the lamp on. ...
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... Normal control loop to have the light in accordance with the variable that is permanently updated in the command control state machine in the Main_pwmx_fluo_demo.c file. The transition from the RUN_MODE state to the LAMP_OFF state is done in the control state machine (control_FBKIT.c file) when the 0. gv_lamp_preset_current gv_lamp_preset_current variable is set to ATAVRFBKIT / EVLB001 User Guide ...
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... Output variables which can impact other state machine ATAVRFBKIT / EVLB001 User Guide TOO_MANY_LAMP_IGNITION_TRIES If the ignition has failed LAMP_IGNITION_MAX_TRIES, able will be set, and the lamp will be switched off thanks to control_FBKIT.c file which will switch off the ballast. The transition from LAMP_OFF to CONFIGURE_LAMP_PREHEAT is done • ...
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... Appendix 1: SWITCH DIM ATAVRFBKIT / EVLB001 User Guide The ballast demonstrator shows that the AT90PWM2B/216 microcontroller can control and regulate fluorescent lamps from any of the two (DALI and switch) methods of dim- ming. It can automatically sense the control method used thereby providing lamp controller manufacturers with maximum flexibility in their design ...
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... C1 charges to Vpk - ATAVRFBKIT / EVLB001 User Guide Small currents for the low voltage supply can be obtained from the AC line at low loss by means of capacitor coupling as shown in the figures below. To esti- mate the required size of the coupling capacitor, use the following relationships for current, charge, voltage and capacitance 1 ...
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... Figure 7-4. Main voltage supply cutting Main Supply Voltage Ipeak = Vin x Ton / L Imean = Ipeak/2 PFC DRIVING Ioff PFC Inductor PFC Switch Ion = (Vin Actual switching frequency is higher than shown ATAVRFBKIT / EVLB001 User Guide Vbus ...
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... Appendix 4: Bill of Material ATAVRFBKIT / EVLB001 User Guide Figure 7-5. Bill of Materials 1 Conclusion 7-28 7597B–AVR–10/07 ...
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... Conclusion Figure 7-6. Bill of Materials 2 7-29 7597B–AVR–10/07 ATAVRFBKIT / EVLB001 User Guide ...
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... Figure 7-7. Bill of Materials 3 ATAVRFBKIT / EVLB001 User Guide Conclusion 7-30 7597B–AVR–10/07 ...
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... Conclusion 7.5 Appendix 5: Schematics 7-31 7597B–AVR–10/ ATAVRFBKIT / EVLB001 User Guide ...
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... ATAVRFBKIT / EVLB001 User Guide Conclusion 7-32 7597B–AVR–10/07 ...
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... Disclaimer: The information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any intellectual property right is granted by this document or in connection with the sale of Atmel products. EXCEPT AS SET FORTH IN ATMEL’S TERMS AND CONDITIONS OF SALE LOCATED ON ATMEL’S WEB SITE, ATMEL ASSUMES NO LIABILITY WHATSOEVER AND DISCLAIMS ANY EXPRESS, IMPLIED OR STATUTORY WARRANTY RELATING TO ITS PRODUCTS INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT ...