L6730C STMicroelectronics, L6730C Datasheet
L6730C
Specifications of L6730C
Related parts for L6730C
L6730C Summary of contents
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... Switching frequency programmable from 100KHz to 1MHz ■ Master/slave synchronization with 180° phase shift ■ Pre-bias start up capability (L6730C) ■ Selectable source/sink or source only capability after soft-start (L6730C) ■ Selectable constant current or hiccup mode overcurrent protection after soft-start (L6730D) Order Codes ...
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... Error amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5.6 Soft start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5.7 Driver section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 5.8 Monitoring and protections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 5.9 Adjustable masking time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 5.10 Multifunction pin (S/O/U L6730C) (CC/O/U L6730D 5.11 Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 5.12 Thermal shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 5.13 Minimum on-time (TON, MIN 5.14 Bootstrap anti-discharging system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 5.14.1 Fan’s power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 5 ...
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... L6730C - L6730D 6 Application details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 6.1 Inductor design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 6.2 Output capacitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 6.3 Input capacitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 6.4 Compensation network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 6.5 Two quadrant or one quadrant operation mode (L6730C L6730 Demoboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 7.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 7.2 PCB layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 8 I/O Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 9 Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 10 POL Demoboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 10.1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 11 Package mechanical data ...
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... During the soft-start phase a constant current protection is provided possible to select (before the device turn-on) the sink-source or the source-only mode capability by acting on a multifunction pin (L6730C). The L6730C disables the sink mode capability during the soft-start in order to allow a proper start-up also in pre-biased output voltage conditions. The L6730D can always sink current and so it can be used to supply the DDR Memory BUS termination. Other features are Master-Slave synchronization (with 180° ...
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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 =4.5V to14V CC OCH VCCDR LDO OSC L6730C PWM ...
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... Table 2. Thermal data Symbol (1) Max. Thermal Resistance Junction to ambient R thJA T Storage temperature range STG T Junction operating temperature range J T Ambient operating temperature range A 1. Package mounted on demoboard 6/50 Parameter = 500KHz) SW CCDR Description L6730C - L6730D Value Unit -0 BOOT PHASE -0 +24 -0 ±1500 ±1000 V ± ...
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... not used the SYNCH pin can be left floating. SW With this pin it is possible: – To enable-disable the sink mode current capability after SS (L6730C); – To enable-disable the constant current OCP after SS (L6730D); – To enable-disable the latch mode for the OVP; ...
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... Fsw 400 If the pin is left open, the switching frequency is 400 KHz. Normally this pin voltage of 1.2V. In OVP the pin is pulled up to 4.5V (only in latched mode). Don’t connect a capacitor from this pin to GND. L6730C - L6730D External Reference V =1.2V REF V =0 ...
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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- current-limit. The valley current is sensed through the low-side MOSFET(s). The internal current generator sources a current of 100 A (I external resistor (R ) ...
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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 V threshold CC 5V BUS Turn-OFF V threshold CC Turn-ON V threshold CC 12V BUS Turn-OFF V threshold CC Turn-ON V threshold OCH Turn-OFF V threshold OCH ...
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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 Gate Drivers R High Side Source Resistance HGATE_ON R High Side Sink Resistance ...
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... CC Test Condition OSC = OPEN; T =0°C~ 125° 0°C~ 125° -40°C~ 125° 0°C~ 125° -40°C~ 125°C J L6730C - L6730D Min Typ Max Unit 376 400 424 KHz 1.188 1.2 1.212 V 1.185 1.2 1.212 V 0.596 0.6 0.605 V 0 ...
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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 an external resistor (R pin and GND or V CCDR maintained at fixed voltage (typ. 1.2V), the frequency is increased (decreased) proportionally to the current sunk (sourced) from (into) the pin ...
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... CCDR least 1µF capacitor to sustain the internal LDO during the recharge of the bootstrap capacitor. V also represents a voltage reference for Tmask pin, S/O/U pin (L6730C) or CC/O/U pin CCDR (L6730D) and PGOOD pin (see If Vcc 5V the internal LDO works in dropout with an output resistance of about 1Ω. ...
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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 clamp operates at about 2V (typ.), while with V reference is 2.5V (typ.). ● ...
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... After that it becomes 10µA until the final charge value of approximately 4V (see Figure 7. Device start-up: Voltage at the SS pin Vss 16/50 are above their turn-ON thresholds (V IN 0.5V 0. L6730C - L6730D is monitored by the OCH pin) IN with an internal current generator. The SS Figure 7.). Vcc V in Vin ...
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... Monitoring and protections) but not entering in HICCUP mode. The soft-start phase ends when Vss reaches 3.5V. After that the over-current-protection triggers the HICCUP mode (L6730C). With the L6730D there is the possibility to set the HICCUP mode or the constant current mode after the soft-start acting on the multifunction pin CC/O/U. With the L6730 the low-side MOSFET(s) management after soft-start phase depends on the S/O/U pin state (see related section) ...
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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 and so the SS capacitor is rapidly discharged. Two different turn-on UVLO thresholds can be set: 4.2V for 5V BUS and 8.6V for 12V BUS ...
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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 dead CCDR time control avoids MOSFETs cross-conduction maintaining very short dead time duration (see Figure 10 ...
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... Figure 12. OVP not latched 20/50 Table 3: Pins connection PGDelay 12.).If OVP latched-mode has been set the low-side MOSFET is turned Figure 13.). In case of latched-mode OVP the OSC pin is forced L6730C - L6730D and Figure [pF] (3) LGate FB OSC 11.); ...
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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 the output voltage. If the converter can sink current, in the most of cases the low-side will be turned-on before the output voltage exceeds the over-voltage threshold, because the error amplifier will throw off balance in advance. Even if the device doesn’ ...
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... HICCUP mode (L6730C): the high-side and low-side MOSFET(s) are turned off, the soft-start capacitor is discharged with a constant current of 10µA and when the voltage at the SS pin reaches 0 ...
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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 overcurrent event. Figure 17. Peak overcurrent-protection in constant-current-protection (L6730D). V OUT ...
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... 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 way the maximum current can be limited Figure 19. Valley OCP (L6730D). V OUT OFF 24/50 L6730C - L6730D Valley th T OFF (Figure 19.). ...
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... GND the resulting masking time is about 260ns. 5.10 Multifunction pin (S/O/U L6730C) (CC/O/U L6730D) With this pin it is possible: ● To enable-disable the sink-mode-current capability (L6730C) or the constant current protection (L6730D) at the end of the soft-start; ● To enable-disable the latch-mode for the OVP; ● ...
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... BUS 0.7 12V BUS 1 12V BUS shows the results of two modules in synchronization. Two or more INDUCTOR CURRENTS EXT SW L6730C - L6730D OVP SINK CC Not Latched Not Not Latched Yes Latched Not Latched Yes Not Latched Not Not Latched Yes Latched Not ...
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... L6730C - L6730D. In fact voltage mode controller the current has not to be sensed to perform the regulation and, in the case of L6730C - L6730D, neither for the over-current protection, given that during the off-time the valley-current-protection can operate. The first advantage related to this feature is the possibility to realize extremely low conversion ratios ...
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... MOTOR. With the L6730D the current can be limited without shutting down the system because a constant-current-protection is provided. In order to vary the MOTOR speed the output voltage of the converter must be varied. Both L6730C and L6730D have a dedicated pin called EAREF (see the related section) that allows providing an external reference to the non- inverting input of the error-amplifier. In these applications the duty cycle depends on the MOTOR’ ...
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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 long time (say 200-300µs) during which there’s no switching activity and the current into the inductor is zero ...
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... During this time the output current is supplied by the output capacitors. Minimizing the response time can minimize the output capacitor size. 30/50 Vin Vout Vout L Fsw I Vin L is the input voltage and L6730C - L6730D (6) is the output voltage. OUT ...
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... Vout Iout ESR ESR 2 Iout L COUT 2 Cout ( Vin , min D 2 Iout L Vout COUT 2 Cout Vout is the maximum duty cycle value that in the L6730C - L6730D is MAX value can be set. The ESR and C OUT 1 Vout I ( ESR L 8 Cout Irms Iout ESR Iout ) Application details ...
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... (R5, C18 and C19). The compensation network has to provide a FB /10) and the highest gain in DC conditions to minimize the SW 1 (13) L Cout ESR ESR 1 (15 (17 L6730C - L6730D 26.). The output voltage is regulated to the depending on the L-Cout resonance LC . OSC (14) Cout 1 (16 (18 OUT IN ...
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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 half of the switching frequency; – P2 – Check the loop gain considering the error amplifier open loop gain. ...
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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 pin (see Chapter 5.10 on page related to the application. One quadrant operation mode permits to have a higher efficiency at light load, because the converter works in discontinuous mode (see in some cases, in order to maintain a constant switching frequency, it’ ...
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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 14V and the output voltage is at 3.3V. The module can deliver an output current in excess of 30A ...
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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 1K8 1% 100mW R10 1K2 1% 100mW R11 2K7 1% 100mW R12 Manufacturer Neohm 0Ω Neohm Neohm Neohm Neohm ...
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... Neohm Kemet Kemet Kemet OSCON 20SA100M AVX Kemet Kemet Kemet Kemet POSCAP 6TPB330M Panasonic L6730C - L6730D Package Supplier SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 ...
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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 value(µF) C4532X5R1E156M C3225X5R0J107M ...
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... This test point is connected to the S/O/U pin (see 40/50 Function Vo V REF input (4.5-14V) and, in this case, jumper G1 must be left open. and Gndcc. In this case the pins 1 and 3 of the jumper G1 must be CCDR L6730C - L6730D pin) and in this case the pin 1 and 2 of the Table 3: Pins connection) ...
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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 different settings of the multifunction pin DIP SWITCH (S/O/U) (CC/O/U). Table 11. ...
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... 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 85.00% 80.00% 75.00% 1 Figure 37. Demoboard efficiency 645KHz 95.00% 90.00% 85.00% 80.00% 75.00% 70.00% 1 42/50 Fsw=400KHz 12V Iout (A) Fsw=645KHz 12V Iout (A) L6730C - L6730D ...
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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 (A) 12V-->3. OUTPUT CURRENT (A) Efficiency 3. 12V 400KHz 700KHz 1MHz 19 43/50 ...
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... Table 9. the part list. Multi-layer-ceramic-capacitors (MLCCs) Manufacturer Neohm Neohm Neohm Neohm Neohm Neohm 0Ω Neohm Neohm Neohm L6730C - L6730D Figure Package Supplier SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 IFARCAD SMD 0603 ...
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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 20V C14 6.8nF C3-C4-C5 15uF C15-C16-C17-C18 100uF L1 1 ...
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... These packages have a Lead-free second level interconnect . The category of second Level Interconnect is marked on the package and on the inner box label, in compliance with JEDEC Standard JESD97. The maximum ratings related to soldering conditions are also marked on the inner box label. ECOPACK trademark. ECOPACK specifications are available at: www.st.com. 46/50 L6730C - L6730D ® ...
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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 “D” does not include mold flash, protrusions or gate burrs. Mold flash, protrusions or gate burrs shall not exceed 0.15mm per side. 2. Dimension “ ...
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... E 3 0.40 Figure 43. Package dimensions 48/50 mm Typ Max 1.00 0.05 0.30 4.1 153.5 2.25 76.8 4.1 153.5 2.25 76.8 0.50 0.60 15.7 L6730C - L6730D inch Min Typ Max 39.4 0.0 7.1 11.8 161.4 88.6 161.4 88.6 19.7 23.6 2.0 ...
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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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... Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America 50/50 Please Read Carefully: © 2006 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com L6730C - L6730D ...