ST2S08B STMicroelectronics, ST2S08B Datasheet
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ST2S08B
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ST2S08B Summary of contents
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... Table 1. Device summary Order code ST2S08BPQR November 2010 Dual synchronous rectification, 1.5 A, 1.5 MHz adjustable step-down switching regulator = 1.2 V OUT ST2S08B is available in the QFN12L ( mm) package. Package QFN12L ( mm) Doc ID 18290 Rev 1 ST2S08B QFN12L ( mm) Packaging Tape and reel www.st.com ...
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... Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 5 Typical application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6 Typical performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 7 General information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 8 Application information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 8.2 Programming the output voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 8.3 Inductor selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 8.4 Input and output capacitor selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 8.5 Layout considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 9 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 10 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2/18 Doc ID 18290 Rev 1 ST2S08B ...
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... ST2S08B 1 Diagram Figure 1. Schematic diagram * Not available on the ST2S08B version. Doc ID 18290 Rev 1 Diagram 3/18 ...
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... Programing pin. It must be floating or connected to GND. Feedback voltage Power ground Switching pin Power input voltage pin Switching pin Power ground Feedback voltage/output voltage Not connect Inhibit pin: - High device on - Low device off Supply for analog circuit System ground Doc ID 18290 Rev 1 Function ST2S08B ...
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... ST2S08B 3 Maximum ratings Table 3. Absolute maximum ratings Symbol V Positive power supply voltage IN_SW V Positive power supply voltage IN_A V Inhibit voltage INH SWITCH voltage Max. voltage of output pin V Feedback voltage/output voltage FB1,2 Current into V pin Common mode input voltage FB T Max junction temperature ...
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... A O (2) Output short-circuit to ground Doc ID 18290 Rev µ 3.3 µH, 3 Min. Typ. Max. 784 800 816 600 1.5 20 1.5 1 1.2 1.3 0.4 2 0.04 10 1.2 1.5 1 0.1 0.1 0.15 0.3 0.2 0 150 15 3 5.3 ST2S08B Unit µ µ MHz % A µA µA Ω Ω °C °C V ...
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... VIN_SW INH NC GND1 C1 4.7 µF Note: R1, R2 and R3, R4 are calculated according to the following equations R2) O1 FB1 - R4) O2 FB2 L2 SW2 VFB2 ST2S08B 3.3 µF SW1 VFB1 GND2 HV GND_A R2 Doc ID 18290 Rev 1 Typical application 3.3 µ µF R4 AM07870v1 V ...
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... 1 LOAD 0.25 0.5 0.75 1 Output current 1 [A] Switching frequency vs. temperature 0 FB1 FB2 - Temperature [°C] Inhibit threshold vs. temperature 100 - [°C] ST2S08B AM07884v1 1.25 1.5 AM07886v1 100 125 AM07889v1 ON OFF 100 125 ...
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... ST2S08B Figure 10. Switching current limitation vs. temperature 2.4 2.2 2 1.8 1.6 1.4 1 Output1 maximum load current IN 0.8 0.6 -50 - Temperature [°C] Figure 12. Inhibit transient INH V = from 5 INH IN O1 Figure 11. Load transient response AM07888v1 50 75 100 125 1 Doc ID 18290 Rev 1 Typical performance characteristics from 250 ...
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... General information 7 General information The ST2S08B is a dual adjustable current mode PWM step-down DC-DC converter complete 1.5 A switching regulator with internal compensation that eliminates the need for additional components. The constant frequency, current mode, PWM architecture and stable operation with ceramic capacitors, results in low, predictable output ripple. ...
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... ST2S08B 8 Application information 8.1 Introduction The following technical information is used for estimating typical external component characteristics using standard equations. Nevertheless strongly recommended to validate the suitability of external components to the application requirements by thoroughly testing any solution at bench level on a real evaluation circuit. 8.2 Programming the output voltage The output voltage for both channels can be adjusted from 0 ...
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... MAX O × × × MAX continuous mode, for the step-down channel, can O_RIPPLE ⎡ ⎤ ⎢ ⎥ ESR × × ⎣ ⎦ OUT SW is the switching frequency. SW Doc ID 18290 Rev 1 ST2S08B . PEAK ...
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... ST2S08B 9 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: www.st.com. ECOPACK registered trademark. Doc ID 18290 Rev 1 Package mechanical data ...
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... L 0.45 14/18 QFN12L (4x4) mechanical data mm. Typ. Max. 0.90 1.00 0.02 0.05 0.20 0.30 0.35 4.00 4.10 2.15 2.25 4.00 4.10 2.15 2.25 0.80 0.55 0.65 Doc ID 18290 Rev 1 inch. Min. Typ. 0.031 0.035 0.001 0.008 0.010 0.012 0.154 0.157 0.079 0.085 0.154 0.157 0.079 0.085 0.031 0.018 0.022 7936361B ST2S08B Max. 0.039 0.002 0.014 0.161 0.089 0.161 0.089 0.026 ...
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... ST2S08B Tape & reel QFNxx/DFNxx (4x4) mechanical data Dim. Min 12 mm. Typ. Max. Min. 330 13.2 0.504 0.795 101 3.898 14.4 4.35 4.35 1 Doc ID 18290 Rev 1 Package mechanical data inch. Typ. Max. 12.992 0.519 3.976 0.567 0.171 0.171 0.043 ...
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... Package mechanical data Figure 13. QFN12L ( mm) footprint recommended data 16/18 Doc ID 18290 Rev 1 ST2S08B ...
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... ST2S08B 10 Revision history Table 7. Document revision history Date Revision 30-Nov-2010 1 Initial release. Doc ID 18290 Rev 1 Revision history Changes 17/18 ...
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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 18/18 Please Read Carefully: © 2010 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com Doc ID 18290 Rev 1 ST2S08B ...