l6730cqtr STMicroelectronics, l6730cqtr Datasheet
l6730cqtr
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l6730cqtr Summary of contents
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... Selectable constant current or hiccup mode overcurrent protection after soft-start (L6730D) Order Codes Part number L6730CQ L6730CQTR L6730C L6730CTR L6730D L6730DTR June 2006 This is preliminary information on a new product foreseen to be developed. Details are subject to change without notice. ...
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Contents Contents 1 Summary description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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L6730C - L6730D 6 Application details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Summary description 1 Summary description The controller is an integrated circuit realized in BCD5 (BiCMOS-DMOS, version 5) fabrication that provides complete control logic and protection for high performance step-down DC-DC and niPOL converters designed to drive N-Channel MOSFETs ...
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L6730C - L6730D 1.1 Functional description Figure 1. Block diagram PGOOD OCL Monitor SS/INH Protection and Ref SYNCH OSC EAREF PGOOD + 0.6V SINK/OVP/UVLO* - 1.2V MASKING TIME TMASK ADJUSTMENT Note: In the L6730D the multifunction pin is: CC/OVP/UVLO. V ...
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Electrical data 2 Electrical data 2.1 Maximum rating Table 1. Absolute maximum ratings Symbol GND and PGND, OCH, PGOOD Boot Voltage BOOT - PHASE V V HGATE - PHASE V BOOT BOOT PHASE ...
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L6730C - L6730D 3 Pin connections and functions Figure 2. Pins connection (top view) PGOO D D ELAY PGOO D D ELAY NCH SY NCH 2 2 SINK/OVP/UVLO ASK TM ASK ...
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Pin connections and functions Table 3. Pins connection T 4 MASK 5 GND COMP 8 SS/INH 9 EAREF 10 OSC 8/50 By connecting this pin ground it is possible to select two different CCDR ...
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L6730C - L6730D Table 3. Pins connection 11 OCL 12 OCH 13 PHASE 14 HGATE 15 BOOT 16 PGND 17 LGATE V 18 CCDR PGOOD A resistor connected from this pin to ground sets the valley- ...
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L6730C - L6730D 4 Electrical characteristics V = 12V 25°C unless otherwise specified CC A Table 4. Electrical characteristics Symbol Parameter V supply current CC V Stand By current quiescent current CC Power-ON Turn-ON ...
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L6730C - L6730D Table 4. Electrical characteristics Symbol Parameter Error Amplifier R EAREF Input Resistance EAREF I I.I. bias current FB Ext Ref Clamp V Error amplifier offset OFFSET G Open Loop Voltage Gain V GBWP Gain-Bandwidth Product SR Slew-Rate ...
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Electrical characteristics Table 5. Thermal characterizations (V Symbol Parameter Oscillator f Initial Accuracy OSC Output Voltage (1.2V MODE) V Output Voltage FB Output Voltage (0.6V MODE) V Output Voltage FB 12/50 = 12V) CC Test Condition OSC = OPEN; T ...
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L6730C - L6730D 5 Device description 5.1 Oscillator The switching frequency is internally fixed to 400KHz. The internal oscillator generates the triangular waveform for the PWM charging and discharging an internal capacitor (F 400KHz). This current can be varied using ...
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Device description 5.2 Internal LDO An internal LDO supplies the internal circuitry of the device. The input of this stage is the V pin and the output (5V) is the V Figure 4. LDO block diagram. 4.5V 14V LDO 5.3 ...
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L6730C - L6730D 5.4 Internal and external references It is possible to set two internal references, 0.6V and 1.2V or provide an external reference from 0V to 2.5V. The maximum value of the external reference depends on the V the ...
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Device description 5.6 Soft start When both V and V CC the start-up phase takes place. Otherwise the SS pin is internally shorted to GND. At start-up, a ramp is generated charging the external capacitor C initial value for this ...
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L6730C - L6730D The reference of the error amplifier is clamped with this voltage (Vss) until it reaches the programmed value: 0.6V or 1.2V. During the soft-start phase the converter works in closed loop. The L6730C can only source current ...
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Device description Figure 9. Sink-mode disabled: Inductor current during and after soft-start (L6730C). During normal operation, if any under-voltage is detected on one of the two supplies (V the SS pin is internally shorted to GND by an internal switch ...
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L6730C - L6730D 5.7 Driver section The high-side and low-side drivers allow using different types of power MOSFETs (also multiple MOSFETs to reduce the R supplied by V while the high-side driver is supplied by the BOOT pin. A predictive ...
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Device description 5.8 Monitoring and protections The output voltage is monitored by the FB pin not within ±10% (typ.) of the programmed value, the Power-Good (PGOOD) output is forced low. The PGOOD signal can be delayed by ...
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L6730C - L6730D Figure 13. OVP latched It must be taken into account that there is an electrical network between the output terminal and the FB pin and therefore the voltage at this pin is not a perfect replica of ...
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Device description Figure 15. OVP with sink disabled: delay on the OVP operation. The L6730D can always sink current and so the OVP will operate always in advance. The device realizes the over-current-protection (OCP) sensing the current both on the ...
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L6730C - L6730D Figure 16. Constant current and Hiccup Mode during an OCP (L6730C). Using the L6730D there is the possibility to set the constant-current-protection also after the soft-start. The following figures show the behaviour of the L6730D during an ...
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Device description Figure 18. Peak OCP in case of heavy overcurrent (L6730D). V OUT OUT If the current is higher than the valley OCP threshold during the off-time, the high-side MOSFET(s) will not be turned-on. In this ...
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L6730C - L6730D During the constant-current-protection if the Vout becomes lower than 80% of the programmed value an UV (under-voltage) is detected and the device enters in HICCUP mode. The under- voltage-lock-out (UVLO) is adjustable by the multifunction pin (see ...
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Device description Table 6. S/O/U pin; CC/O/U pin R1 R2 N.C 0 11K 2.7K 6.2K 2.7K 4.3K 2.7K 2.7K 2.7K 1.8K 2.7K 1.2K 2.7K 0 N.C 5.11 Synchronization The presence of many converters on the same board can generate beating ...
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L6730C - L6730D 5.12 Thermal shutdown When the junction temperature reaches 150°C ±10°C the device enters in thermal shutdown. Both MOSFETs are turned OFF and the soft-start capacitor is rapidly discharged with an internal switch. The device does not restart ...
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Device description 5.14 Bootstrap anti-discharging system This built-in system avoids that the voltage across the bootstrap capacitor becomes less than 3.3V. An internal comparator senses the voltage across the external bootstrap capacitor keeping it charged, eventually turning-on the low-side MOSFET ...
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L6730C - L6730D 5.14.2 No-sink at zero current operation The L6730C can work in no-sink mode. If output current is zero the converter skip some pulses and works with a lower switching frequency. Between two pulses can pass a relatively ...
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Application details 6 Application details 6.1 Inductor design The inductance value is defined by a compromise between the transient response time, the efficiency, the cost and the size. The inductor has to be calculated to maintain the ripple current (∆I ...
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L6730C - L6730D 6.2 Output capacitors The output capacitors are basic components for the fast transient response of the power supply. They depend on the output voltage ripple requirements, as well as any output voltage deviation requirement during a load ...
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Application details 6.4 Compensation network The loop is based on a voltage mode control internal/external reference voltage and scaled by the external resistor divider. The error amplifier output V COMP width modulated (PWM) with an amplitude the ...
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L6730C - L6730D ● Compensation network design: – Put the gain R Place before the output filter resonance – Z1 Place at the output filter resonance – Z2 Place at the output capacitor ESR zero – P1 Place at one ...
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Application details 6.5 Two quadrant or one quadrant operation mode (L6730C) After the soft-start phase the L6730C can work in source only (one quadrant operation mode sink/source (two quadrant operation mode), depending on the setting of the multifunction ...
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L6730C - L6730D 7 L6730 Demoboard 7.1 Description L6730 demoboard realizes in a four layer PCB a step-down DC/DC converter and shows the operation of the device in a general purpose application. The input voltage can range from 4.5V to ...
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L6730 Demoboard 7.2 PCB layout Figure 30. Top layer Figure 32. Signal ground layer 36/50 Figure 31. Power ground layer Figure 33. Bottom layer L6730C - L6730D ...
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L6730C - L6730D Figure 34. Demoboard schematic Table 7. Demoboard part list Reference Value R1 820Ω N.C. R4 10Ω 1% 100mW R5 11K 1% 100mW R6 6K2 1% 100mW R7 4K3 1% 100mW R8 2K7 1% 100mW R9 ...
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... IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD RADIAL 10X10.5 SANYO SMA6032 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD SANYO SMD ST SOT23 IFARCAD DO216AA STMicroelectronics SO8 STMicroelectronics SO8 STMicroelectronics HTSSOP20 STMicroelectronics STMicroelectronics ...
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L6730C - L6730D Table 8. Other inductor manufacturer Manufacturer WURTH ELEKTRONIC SUMIDA EPCOS TDK TOKO COILTRONICS Table 9. Other capacitor manufacturer Manufacturer TDK NIPPON CHEMI-CON PANASONIC Series Inductor Value (µH) 744318180 CDEP134-2R7MC-H HPI_13 T640 SPM12550T-1R0M220 FDA1254 HCF1305-1R0 HC5-1R0 Series Capacitor ...
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I/O Description 8 I/O Description Figure 35. Demoboard Table 10. I/O Functions Symbol The input voltage can range from 1.8V to 14V. If the input voltage is between 4.5V and 14V Input ( can supply also the ...
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L6730C - L6730D Table 10. I/O Functions SYNCH This pin is connected to the synch pin of the controller (see PWRGD This pin is connected to the PGOOD pin of the controller. Different positions of the dip switch correspond to ...
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Efficiency 9 Efficiency The following figures show the demoboard efficiency versus load current for different values of input voltage and switching frequency: Figure 36. Demoboard efficiency 400KHz 95.00% 90.00 ...
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L6730C - L6730D Figure 38. Demoboard efficiency 1MHz 95.00% 90.00% 85.00% 80.00% 75.00% 70.00% 65.00% 60.00% 1 Figure 39. Efficiency with 2xSTS12NH3LL+2XSTSJ100NH3LL 0.96 0.95 0.94 0.93 0.92 0.91 0.9 0.89 0.88 0. Fsw=1MHz Iout ...
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POL Demoboard 10 POL Demoboard 10.1 Description A compact demoboard has been realized to manage currents in the range of 10-15A. 36. shows the schematic and have been used on the input and the output in order to reduce the ...
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L6730C - L6730D Table 12. Pol demoboard part list. R11 15Ω 1% 100mW R12 4K7 1% 100mW R13 1K 1% 100mW R14 2.2Ω R15 2.2Ω C1-C7 220nF C6- C19-C20-C9 100nF C2 1nF C11 N.C. C12 68nF C13 220pF C8 4.7uF ...
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Package mechanical data 11 Package mechanical data In order to meet environmental requirements, ST offers these devices in ECOPACK packages. These packages have a Lead-free second level interconnect . The category of second Level Interconnect is marked on the package ...
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L6730C - L6730D Table 13. HTSSOP20 mechanical data DIM. Min 0.800 b 0.190 c 0.090 (1) 6.400 D (3) 2.200 D1 E 6.200 (2) 4.300 E1 (3) 1.500 0.450 L1 k aaa 1. Dimension ...
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Package mechanical data Table 14. QFN 4mm x 4mm 24L mechanical data Dim Min A A1 0.00 b 0.18 D 3.9 D2 1.95 E 3 0.40 Figure 43. Package dimensions 48/50 mm Typ Max 1.00 0.05 ...
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L6730C - L6730D 12 Revision history Table 15. Revision history Date Revision 21-Dec-2005 07-Jun-2006 1 Initial release. 2 Added QFN package information, new template Revision history Changes 49/50 ...
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