L6599ATD STMicroelectronics, L6599ATD Datasheet

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... Desktop PCs, entry-level servers ■ Telecom SMPS ■ High efficiency industrial SMPS ■ AC-DC adapters, open frame SMPS Table 1. Device summary Order codes L6599ATD L6599ATDTR L6599ATN October 2009 Improved high-voltage resonant controller DIP16 Package SO16N SO16N DIP16 Doc ID 15534 Rev 3 L6599AT ...

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Contents Contents 1 Device description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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L6599AT 1 Device description The L6599AT is a temperature-extended version of the L6599A double-ended controller specifically designed for the series-resonant half-bridge topology. It provides a 50% complementary duty cycle: the high-side switch and the low-side switch are ...

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Block diagram 2 Block diagram Figure 1. Block diagram 4/31 Doc ID 15534 Rev 3 L6599AT ...

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L6599AT 3 Pin connection Figure 2. Pin connection (top view) Table 2. Pin description Pin n° Type 1 Css 2 DELAY 3 CF Function Soft-start. This pin connects an external capacitor to GND and a resistor to RFmin (pin 4) ...

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Pin connection Table 2. Pin description (continued) Pin n° Type 4 RFmin 5 STBY 6 ISEN 7 LINE 8 DIS 6/31 Function Minimum oscillator frequency setting. This pin provides a precise 2 V reference and a resistor connected from this ...

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L6599AT Table 2. Pin description (continued) Pin n° Type 9 PFC_STOP 10 GND 11 LVG 12 Vcc 13 N.C. 14 OUT 15 HVG 16 VBOOT Function Open-drain ON/OFF control of PFC controller. This pin, normally open, is intended for stopping ...

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Electrical data 4 Electrical data 4.1 Absolute maximum ratings Table 3. Absolute maximum rating Symbol Pin V 16 BOOT V 14 OUT dV /dt 14 OUT Vcc PFC_STOP I 9 PFC_STOP V 7 LINEmax I 4 RFmin ...

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L6599AT 5 Electrical characteristics T = -40 to 125 °C, Vcc = kΩ; unless otherwise specified RFmin Table 5. Electrical characteristics Symbol IC supply voltage Vcc Operating range Vcc Turn-on threshold On Vcc ...

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Electrical characteristics Table 5. Electrical characteristics (continued) Symbol DIS function I Input bias current DIS Vth Disable threshold Oscillator D Output duty cycle f Oscillation frequency osc T Dead-time D V Peak value CFp V Valley value CFv V Voltage ...

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L6599AT Table 5. Electrical characteristics (continued) Symbol Vth Restart threshold 3 Low-side gate driver (voltages referred to GND) V Output low voltage LVGL V Output high voltage LVGH I Peak source current sourcepk I Peak sink current sinkpk t Fall ...

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Application information 6 Application information The L6599AT is an advanced double-ended controller specifically designed for resonant half-bridge topology (see half-bridge leg are alternately switched on and off (180° out-of-phase) for exactly the same time interval. This is commonly referred to ...

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L6599AT Figure 4. Typical system block diagram 6.1 Oscillator The oscillator is programmed externally by means of a capacitor (CF) connected from pin 3 (CF) to ground, which is alternately charged and discharged by the current defined with the network ...

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Application information Figure 5. Oscillator internal block diagram The following approximate relationships hold for the minimum and the maximum oscillator frequency respectively: Equation 1 After fixing CF in the hundred range (consistent with the maximum source capability ...

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L6599AT Figure 6. Oscillator waveforms and their relationship with gate-driving signals In Figure 6 the timing relationship between the oscillator waveform and the gate-drive signal, as well as the swinging node of the half-bridge leg (HB) is shown. Note that ...

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Application information Figure 7. Burst-mode implementation: a) narrow input voltage range; b) wide input voltage range Essentially, RF max burst-mode operation. Once fixed f Equation 3 Note that, unlike the associated to a load Pout max transformer's ...

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L6599AT no-load consumption of this stage (0.5 1 W). There is no compliance issue because EMC regulations on low-frequency harmonic emissions refer to nominal load limit is imposed when the converter operates with light or no load. To ...

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Application information 6.3 Soft-start Generally speaking, the purpose of soft-start is to progressively increase the converter's power capability when it is started up avoid excessive inrush current. In resonant converters the deliverable power depends inversely on frequency, ...

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L6599AT Equation 5 where f is recommended least 4 times f start quite empirical and is a compromise between an effective soft-start action and an effective OCP (see next section). Please refer to the timing diagram of ...

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Application information Figure 11. Current sensing techniques: a) with sense resistor, b) “lossless”, with capacitive shunt The L6599AT is equipped with a current sensing input (pin 6, ISEN) and a sophisticated overcurrent management system. The ISEN pin is internally connected ...

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L6599AT The circuit shown in series small (not above a few hundred ohms, just to limit current spiking) the circuit A operates like a capacitive current divider low-loss type, and the sense resistor R ...

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Application information Figure 12. Soft-start and delayed shutdown upon overcurrent timing diagram This function is achieved with pin 2 (DELAY), by means of a capacitor C resistor R connected to ground. As the voltage on the ISEN pin exceeds 0.8 ...

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L6599AT The timing diagram in voltage of the L6599AT (V event and does not restart immediately after V is still higher than 0.3 V. Also the PFC_STOP pin stays low as long as V(DELAY) is greater than 0.3 V. Note ...

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Application information Figure 13. Line sensing function: internal block diagram and timing diagram With reference to (Vin ) and OFF (Vin ON Equation 11 Vin which, solved for R Equation 12 While the line undervoltage is active the start-up generator ...

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L6599AT the function is not used the pin must be connected to a voltage greater than 1.24 V but lower than 6 V (worst-case value of the 7 V threshold). 6.7 Bootstrap section The supply of the floating high-side section ...

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Application information Equation 13 where Q is the gate charge of the external power MOS bootstrap DMOS (150 W, typ.) and T equals about half the switching period minus the dead time T MOSFET with a total gate ...

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L6599AT Figure 15. Application example AC-DC adapter using L6563 and L6599AT Doc ID 15534 Rev 3 Application information 27/31 ...

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Package mechanical data 7 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 ...

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L6599AT Figure 17. SO16N mechanical data DIM. MIN 0 0. ( (1) 3 4. (1) "D" and "F" do not ...

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Revision history 8 Revision history Table 6. Document revision history Date 05-Jun-2009 11-Aug-2009 30-Oct-2009 30/31 Revision 1 Initial release. 2 Updated Table 5 on page 9 3 Updated Table 5 on page 9 Doc ID 15534 Rev 3 L6599AT Changes ...

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... L6599AT 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. ...