View ST1S0307_1317315.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

ST1S03
1.5A, 1.5 MHz adjustable, step-down switching regulator in DFN6
Features

Step-down current mode PWM (1.5MHz) DC-DC converter 2% DC output voltage tolerance Internal soft start for START-UP current limitation and power on delay of 50-100s Typical efficiency: > 70% over all operating conditions 1.5A Output current capability Not switching quiescent current: max 2.5mA over temperature range Switch VDS: max 350mV @ ISW=750mA Uses tiny capacitors and inductors Available in DFN 3x3 exposed pad over an input voltage range of 3V to 16V. An high switching frequency (1.5MHz) allows the use of tiny surface-mount components: as well as the resistor divider to set the output voltage value, only an inductor, a schottky diode and two capacitors are required. Besides, a low output ripple is guaranteed by the current mode PWM topology and by the use of low E.S.R. SMD ceramic capacitors. The device is thermal protected and current limited to prevent damages due to accidental short circuit. The ST1S03 is available in DFN6.
DFN6 (3x3mm)
Description
The ST1S03 is a step down DC-DC converter optimized for powering low-voltage digital core in HDD applications and, generally, to replace the high current linear solution when the power dissipation may cause an high heating of the application environment. It provides up to 1.5A
Order codes
Part number ST1S03PM ST1S03PU March 2007 Packaging ST1S03PMR ST1S03PUR Rev. 5 Package DFN6 (3x3 mm) DFN6D (3x3 mm) 1/17
www.st.com
17
ST1S03
Contents
1 2 3 4 5 6 7 8 9 Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Application notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Typical application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Typical performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2/17
ST1S03
Diagram
1
Figure 1.
Diagram
Schematic diagram
3/17
Pin configuration
ST1S03
2
Figure 2.
Pin configuration
Pin connections (top view)
Table 1.
Pin N 1 2 3 4 5 6
Pin description
Symbol VFB GND SW VIN_SW VIN_A N.C. Voltage of Feedback System Ground Output of the internal Power Switch Power Supply for the MOSFET Switch Power Supply for the Analog Circuit Not Connected Name and function
4/17
ST1S03
Maximum ratings
3
Table 2.
Maximum ratings
Absolute maximum ratings
Parameter Positive Power Supply Voltage Positive Power Supply Voltage Max Voltage of output pin Feedback Voltage Common mode input voltage Max Junction Temperature Storage Temperature Range Lead Temperature (Soldering) 10 Sec. Value -0.3 to 16 -0.3 to 16 -0.3 to 16 2.5 1 150 -25 to 150 300 Unit V V V V mA C C C
Symbol VI_SW VI_SW SWITCH Voltage VFB IVFB TJ TSTG TLEAD
Note:
Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional Operation under these conditions is not implied.
Thermal data
Parameter Thermal resistance junction-case Thermal resistance junction-ambient Value 10 55 Unit C/W C/W
Table 3.
Symbol RthJC RthJA
5/17
Electrical characteristics
ST1S03
4
Table 4.
Symbol FB PSRR IFB BW IQ IO IMIN
Electrical characteristics
Electrical characteristics (VIN_SW = VIN_A = 5V, CI = 4.7F, CO = 22F, L1 = 3.3H, TJ = 0 to 125C, unless otherwise specified. Typical values are referred to 25C)
Parameter Feedback voltage Feedback PSRR VFB Pin bias current Bandwidth of error amplifier Quiescent current Output current Minimum output current VIN = 3V to 16V IO = 10mA to 1.2A VFB = 0.8V, TA =25C 1.2 Closed Loop No Switching VIN =3V to 16V 1.5 1 0.032 0.0014 1.5 87 1.65 ISW = 750 mA IO =10mA to 1.2A
(1)
Test Conditions
Min. 784
Typ. 800 -60
Max. 816
Unit mV dB
1Hz < Frequency VIN
600 300 2.5
nA KHz mA A mA
%VO/VIN Reference line regulation %VO/IO PWM fS DMAX ISWL VDS E TSHDN THYS VO/IO Reference load regulation PWM Switching frequency (1) Maximum duty cycle Switching current limitation Switch VDS Efficiency Thermal shut down
0.06 0.003 1.8
%VO/ VIN %VO/ mA MHz % A
200 70 130 150 15
350
mV % C C
Thermal shut down hysteresis (1) Load transient response (1) IO = 100mA to 700mA tR = tF 100ns, TA = 25C -5
+5 +5
%VO %VO
VO/IO@ Short circuit removal response(1) IO = 10mA to short, TA = 25C IO=short
1. Guaranteed by design, but not tested in production.
6/17
ST1S03
Application notes
5
Application notes
The ST1S03 is an adjustable current mode PWM step-down DC/DC converter with internal 1.5A power switch, packaged in 6-lead DFN 3x3. It's a complete 1.5A switching regulator with its internal compensation eliminating additional component. The constant frequency, current mode, PWM architecture and stable operation with ceramic capacitors results in low, predictable output ripple. However, in order to keep the output regulated, the devices goes in pulse skipping mode when a very light load is required. To clamp the error amplifier reference voltage a Soft Start control block generating a voltage ramp, has been implemented. Besides an On-Chip Power on Reset of 50 = 100s ensure the proper operation when switching on the power supply. Other circuits fitted to the device protection are the Thermal Shut down block which turn off the regulator when the junction temperature exceeds 150C typically and the Cycle-by-cycle Current Limiting that provides protection against shorted outputs. Being the ST1S03 an adjustable regulator, the output voltage is determined by an external resistor divider. The desired value is given by the following equation: VO = VFB [1+R1/R2] To make the device working, only other four external components are required: a Schottky diode, an inductor and two capacitors. The chosen inductor must be able to not saturate at the peak current level. Besides, its value can be selected keeping in account that a large inductor value increases the efficiency at low output current and reduces output voltage ripple, while a smaller inductor can be chosen when it is important to reduce the package size and the total cost of the application. Finally, the ST1S03 has been designed to work properly with X5R or X7R SMD ceramic capacitors both at the input and at the output. this kind of capacitors, thanks to their very low series resistance (ESR), minimize the output voltage ripple. Other low ESR capacitors can be used according to the need of the application without invalidating the right functioning of the device. Due to the high switching frequency and peak current, it is important to optimize the application environment reducing the length of the PCB traces and placing all the external component near the device.
7/17
Typical application
ST1S03
6
Figure 3.
Typical application
Application circuits
8/17
ST1S03
Typical performance characteristics
7
Figure 4.
Typical performance characteristics
(L1=3.3H, CI = 4.7F, CO = 22F, unless otherwise specified) Load voltage feedback vs temp. Figure 5. Voltage feedback vs temperature
Figure 6.
Line output voltage regulation vs temperature
Figure 7.
Line voltage feedback vs temperature
Figure 8.
Voltage feedback vs output current Figure 9.
PWM Switching frequency vs temperature
9/17
Typical performance characteristics
ST1S03
Figure 10. Quiescent current vs temperature
Figure 11. Quiescent current vs input voltage
Figure 12. Minimum operating voltage vs output voltage
Figure 13. Efficiency vs temperature
Figure 14. Efficiency vs output current
Figure 15. Switch VDS vs temperature
10/17
ST1S03
Typical performance characteristics
Figure 16. Switch RDS-ON vs temperature
Figure 17. Switch current limitation vs temperature
Figure 18. Load transient response
Figure 19. Load transient response
VCC=5V, IO=100mA to 780mA, CI=4.7F, CO=22F, L=3.3H, TON=38s, TJ=25C
VCC=5V, IO=200mA to 1.2A, CI=4.7F, CO=22F, L=3.3H, TON=38s, TJ=25C
Figure 20. Start-Up transient
Figure 21. Start-Up transient
VCC = 5V, TJ = 25C
VCC = 5V, TJ = 25C
11/17
Package mechanical data
ST1S03
8
Package mechanical data
In order to meet environmental requirements, ST offers these devices in ECOPACK(R) packages. 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 is an ST trademark. ECOPACK specifications are available at: www.st.com.
12/17
ST1S03
Package mechanical data
DFN6 (3x3) MECHANICAL DATA
mm. DIM. MIN. A A1 A2 A3 b D D2 E E2 e L L1 L2 K 0.20 0.20 0.24 0.13 0.008 0.33 2.90 1.92 2.90 1.11 0.95 0.45 0.008 0.009 0.005 3.00 3.00 0.80 0 0.65 0.20 0.43 3.10 2.12 3.10 1.31 0.013 0.114 0.076 0.114 0.044 0.037 0.018 0.118 0.118 TYP MAX. 1.00 0.05 0.75 MIN. 0.031 0.0 0.026 0.08 0.017 0.122 0.083 0.122 0.052 TYP. MAX. 0.039 0.02 0.030 inch.
7387339A
13/17
Package mechanical data
ST1S03
DFN6D (3x3) MECHANICAL DATA
mm. DIM. MIN. A A1 A3 b D D2 E E2 e L 0.30 0.23 2.90 2.23 2.90 1.50 0.95 0.40 0.50 0.012 3.00 3.00 0.80 0 0.02 0.20 0.45 3.10 2.50 3.10 1.75 0.009 0.114 0.088 0.114 0.059 0.037 0.016 0.020 0.118 0.118 TYP MAX. 1.00 0.05 MIN. 0.031 0 0.001 0.008 0.018 0.122 0.098 0.122 0.069 TYP. MAX. 0.039 0.002 inch
7946637B
14/17
ST1S03
Package mechanical data
Tape & Reel QFNxx/DFNxx (3x3) MECHANICAL DATA
mm. DIM. MIN. A C D N T Ao Bo Ko Po P 3.3 3.3 1.1 4 8 12.8 20.2 60 18.4 0.130 0.130 0.043 0.157 0.315 TYP MAX. 330 13.2 0.504 0.795 2.362 0.724 MIN. TYP. MAX. 12.992 0.519 inch
15/17
Revision history
ST1S03
9
Table 5.
Date
Revision history
Revision history
Revision 1 2 3 4 5 First Release. Maturity Change. Mistake on Figure 1, TJ is changed 125 ==> 150C on Table 3. Add new package SO-8 exposed pad. Package SO-8 has been removed and the document has been reformatted. Changes
11-Nov-2004 08-Feb-2005 03-Mar-2005 13-Jul-2005 29-Mar-2007
16/17
ST1S03
Please Read Carefully:
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. Purchasers are solely responsible for the choice, selection and use of the ST products and services described herein, and ST assumes no liability whatsoever relating to the choice, selection or use of the ST products and services described herein. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. If any part of this document refers to any third party products or services it shall not be deemed a license grant by ST for the use of such third party products or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoever of such third party products or services or any intellectual property contained therein.
UNLESS OTHERWISE SET FORTH IN ST'S TERMS AND CONDITIONS OF SALE ST DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY WITH RESPECT TO THE USE AND/OR SALE OF ST PRODUCTS INCLUDING WITHOUT LIMITATION IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY JURISDICTION), OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT. UNLESS EXPRESSLY APPROVED IN WRITING BY AN AUTHORIZED ST REPRESENTATIVE, ST PRODUCTS ARE NOT RECOMMENDED, AUTHORIZED OR WARRANTED FOR USE IN MILITARY, AIR CRAFT, SPACE, LIFE SAVING, OR LIFE SUSTAINING APPLICATIONS, NOR IN PRODUCTS OR SYSTEMS WHERE FAILURE OR MALFUNCTION MAY RESULT IN PERSONAL INJURY, DEATH, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE. ST PRODUCTS WHICH ARE NOT SPECIFIED AS "AUTOMOTIVE GRADE" MAY ONLY BE USED IN AUTOMOTIVE APPLICATIONS AT USER'S OWN RISK.
Resale of ST products with provisions different from the statements and/or technical features set forth in this document shall immediately void any warranty granted by ST for the ST product or service described herein and shall not create or extend in any manner whatsoever, any liability of ST.
ST and the ST logo are trademarks or registered trademarks of ST in various countries. Information in this document supersedes and replaces all information previously supplied. The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners.
(c) 2007 STMicroelectronics - All rights reserved STMicroelectronics group of companies 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 www.st.com
17/17

▲Up To Search▲

Price & Availability of ST1S0307

	To Download ST1S0307 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .