L5973AD STMicroelectronics, L5973AD Datasheet
L5973AD
Specifications of L5973AD
497-1417-5
497-4565-5
E-L5973AD
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Related parts for L5973AD
L5973AD Summary of contents
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... CERAMIC November 2009 2 A switch step down switching regulator Description The L5973AD is a step down monolithic power switching regulator with a switch current limit able to deliver more than 1 current to the load depending on the application conditions. The output voltage can be set from 1.235 ...
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... Inhibit function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 4.8 Thermal shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5 Additional features and protections . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.1 Feedback disconnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.2 Output overvoltage protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.3 Zero load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.4 Application circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 6 Application ideas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 7 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 8 Order code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 9 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 2/22 Doc ID 9552 Rev 9 L5973AD ...
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... L5973AD 1 Pin settings 1.1 Pin connection Figure 2. Pin connection (top view) 1.2 Pin description Table 1. Pin description N° Type 1 OUT 2 SYNC 3 INH 4 COMP VREF 7 GND 8 VCC OUT 1 8 SYNC 2 7 INH 3 6 COMP 4 5 D98IN955 Description Regulator output. Master/slave synchronization. When it is open, a signal synchronous with the turn-off of the internal power is present at the pin ...
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... Operating junction temperature range J T Storage temperature range STG 2.2 Thermal data Table 3. Thermal data Symbol R Maximum thermal resistance junction-ambient thJA 1. Package mounted on board 4/22 Parameter ≤ 60 °C A Parameter Doc ID 9552 Rev 9 L5973AD Value Unit int. limit -0. -0 2.25 W -40 to 150 °C -55 to 150 ° ...
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... L5973AD 3 Electrical characteristics ° unless otherwise specified J CC Table 4. Electrical characteristics Symbol Operating input voltage V CC range MOSFET on R DS(on) resistance Maximum limiting I l current f Switching frequency s Duty cycle Dynamic characteristics (see test circuit). V Voltage feedback 5 η Efficiency DC characteristics Total operating ...
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... V COMP 0.74 V sync V = 2.33 V sync source no load, V sync REF REF REF Doc ID 9552 Rev 9 Min Typ Max 2.3 2.5 V REF 0.74 (1) 0.11 0.25 0.21 0.45 2. 1.65 V 0.20 0.35 3.234 3.3 3.366 3.2 3.3 3.399 L5973AD Unit μ ...
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... L5973AD 4 Functional description The main internal blocks are shown in They are: ● A voltage regulator that supplies the internal circuitry. From this regulator, a 3.3 V reference voltage is externally available. ● A voltage monitor circuit that checks the input and internal voltages. ● A fully integrated sawtooth oscillator whose frequency is 500 kHz ● ...
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... Master and Slave. As Master to synchronize external devices to the internal switching frequency. As Slave to synchronize itself by external signal. 8/22 Figure 4) consists of a start-up circuit, an internal , STARTER IC BIAS D00IN1126 Doc ID 9552 Rev 9 and the voltages go higher than ref bg PREREGULATOR VREG BANDGAP VREF L5973AD that REG (UVLO). CC ...
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... Ibias_osc GENERATOR 4.4 Current protection The L5973AD has two current limit protections, pulse by pulse and frequency fold back. The schematic of the current limitation circuitry for the pulse by pulse protection is shown in Figure 6. The output power PDMOS transistor is split in two parallel PDMOS. The smallest one has a ...
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... Output voltage swing Input bias current The error amplifier output is compared with the oscillator sawtooth to perform PWM control. 10/22 VCC RSENSE I OFF A1 OUT PWM Doc ID 9552 Rev 9 RTH NOT I I D00IN1134 2300 μ 1500 μA/300 μA 0.4 V/3.65 V 2.5 μA L5973AD ...
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... L5973AD 4.6 PWM comparator and power stage This block compares the oscillator sawtooth and the error amplifier output signals generating the PWM signal for the driving stage. The power stage is a very critical block cause it has to guarantee a correct turn on and turn OFF of the PDMOS. The turn ON of the power element, or better, the rise time of the current at turn on very critical parameter to compromise ...
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... PDMOS area, so ensuring an accurate and fast temperature detection. An hysteresis of approximately 20 °C avoids that the devices turns on and off continuously 12/22 CLAMP GATE OFF ON/OFF CONTROL ON Doc ID 9552 Rev 9 L5973AD VCC I OFF PDMOS VOUT DRAIN L I LOAD ESR ...
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... L5973AD 5 Additional features and protections 5.1 Feedback disconnection In case of feedback disconnection, the duty cycle increases versus the maximum allowed value, bringing the output voltage close to the input supply. This condition could destroy the load. To avoid this dangerous condition, the device is turned off if the feedback pin remains floating ...
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... K, 1%, 0.1 W 0603 4.7 K, 1%, 0.1 W 0603 STPS2L25U DO3316P-153 Doc ID 9552 Rev 9 L1 15μH OUT STPS2L25U 5. 3.3K D03IN1454 Description Manufacturer 10 μ MURATA 330 μF, 6.3 V Sanyo 220 pF, 5 KEMET 22 nF, 10 KEMET Neohm Neohm Neohm μ COILCRAFT L5973AD VOUT=3.3V C2 330μF 6.3V ...
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... L5973AD Figure 9. Junction temperature vs output current Tj(°C ) Tj(°C ) 100 100 90 90 Vin=5V Vin= Tam b=25°C Tam b=25° 0.2 0.2 0.4 0.4 0.6 0.6 0.8 0 1.2 1.2 Io(A ) Io(A ) Figure 11. Efficiency vs output current Vin=5V Vin= 0.2 0.2 0.4 0.4 0.6 ...
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... GND 22nF C2 R3 220pF 4.7K D03IN1456 Doc ID 9552 Rev 9 L1 15μH OUT 1 D1 STPS2L25U 2. GND 100μF 24K 16V D03IN1455 D2 1N4148 N1/N2=2 OUT Lp 22μH D1 STPS25L25U FB C4 100μF 10V L5973AD VOUT=-12V/ 0.6A VOUT1=5V/ 50mA VOUT=3.3V/ 0.5A C5 47μF 10V ...
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... L5973AD Refer to L5973AD application note (AN1723) to have additional information, details, and more application ideas. L5973AD belongs to L597x family. Related part numbers are: ● L5970D: 1 ● L5972D ● L5973D: 2 case higher current is needed, the nearest DC-DC Converter family is L497x. ), 250 kHz step down DC-DC Converter in SO8 ...
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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 at: ECOPACK trademark. 18/22 Doc ID 9552 Rev 9 L5973AD www.st.com. ...
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... L5973AD Table 7. HSOP8 mechanical data Dim ccc Figure 16. Package dimensions mm. Min Typ Max 1.70 0.00 0.15 1.25 0.31 0.51 0.17 0.25 4.80 4.90 5.00 3 3.1 3.2 5.80 6.00 6.20 3.80 3.90 4.00 2.31 2.41 2.51 1.27 0.25 0.50 0.40 1. 0.10 Doc ID 9552 Rev 9 ...
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... Order code 8 Order code Table 8. Ordering information Order code L5973AD L5973ADTR 20/22 Package HSOP8 (Exposed pad) HSOP8 (Exposed pad) Doc ID 9552 Rev 9 L5973AD Packaging Tube Tape and reel ...
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... L5973AD 9 Revision history Table 9. Document revision history Date December 2003 January 2004 December 2004 November 2005 14-Dec-2006 15-Jan-2007 11-Oct-2007 24-Oct-2007 01-Nov-2009 Revision 1 First Issue 2 Migration to EDOCS 3 Added D1 and E1 dimensions in HSOP8 package information. 4 Updated the package information section. V value updated been reformatted. ...
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... Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Philippines - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America 22/22 Please Read Carefully: © 2009 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com Doc ID 9552 Rev 9 L5973AD ...