 |
|
| If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
|
|
| If you can't view the Datasheet, Please click here to try to view without PDF Reader . |
|
|
| Datasheet File OCR Text: |
| ST735S ST735T 300kHz, -5V/ADJ INVERTING, NEGATIVE OUTPUT CURRENT-MODE PWM REGULATOR s s s s s s s s s s s CONVERTS +4.0V TO + 6.2V INPUT TO -5V OUTPUT (735S) OR +3.5V TO + 9.0V TO A NEGATIVE ADJUSTABLE OUTPUT (735T) 1W GUARANTEED OUTPUT POWER 72% TYPICAL EFFICIENCY 0.8mA QUIESCENT CURRENT 1A SHUTDOWN MODE 300KHZ FIXED FREQUENCY OSCILLATOR CURRENT MODE PWM CONVERTER LOW NOISE AND JITTER SOFT START SIMPLE APPLICATION CIRCUIT UNDERVOLTAGE LOCKOUT (735S) DIP-8 SO-8 DESCRIPTION The ST735S/ST735T is a Bi-CMOS, inverting switch mode DC-DC regulator with internal Power MOSFET that generates a fixed -5V (S version) or a negative adjustable (T version) output voltage from a 4V (3.5V for the 735T) to 6.2V input voltage (9V for the 735T); is guaranteed an output current of 200mA for inputs greater than 4.5V. The quiescent current for this device is typically of SCHEMATIC DIAGRAM 0.8mA and, in shutdown mode it is reduced to 1A. These power-conserving features, along with high efficiency and applications circuits, thaT lend itself to minaturization, make the ST735S/ST735T excellent in a broad range of on-card, HDD and portable equipment applications. These device employ a high performance current mode pulse with modulation (PWM) control scheme to provide tight output voltage regulation and low noise. The fixed frequency oscillator is factory trimmed to 300KHz, allowing for easy noise filtering. The regulator in production is tested to guarantee an output accuracy within 5% over all specified conditions. October 2002 1/11 ST735S/ST735T ABSOLUTE MAXIMUM RATINGS Symbol VIN VIN SHDN VLX VFB VOUT ILX Ptot Tstg Top Parameter DC Input Voltage (VIN to GND) for ST735S DC Input Voltage (VIN to GND) for ST735T (Note 1) Shutdown Voltage (SHDN to GND) Switch Voltage (Lx to VIN) Feedback Voltage (VOUT to GND) Output Voltage (VOUT to GND) Other Input Voltage (SS, CC to GND) Peack Switch Current Power Dissipation at Tj = 70C Storage Temperature Range Operating Junction Temperature Range DIP-8 SO-8 Value -0.3 to +7 -0.3 to +11 -0.3 to VIN+0.3 -12.5 to +0.3 -11 to +0.3 -11 to +0.3 -0.3 to V++0.3 2 725 470 -55 to +150 -40 to +125 Unit V V V V V V V A mW C C Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. Note 1: The input to output differential voltage is limited to VIN+|VOUT|<12.7V THERMAL DATA Symbol Rthj-case Parameter Thermal Resistance Junction-case DIP-8 2 SO-8 8 Unit C/W CONNECTION DIAGRAM (top view) PIN DESCRIPTION Pin N 1 2 3 4 5 6 7 8 Symbol SHDN VREF SS CC VOUT GND LX VIN Reference Output Voltage Soft Start Compensation Input Negative Output Voltage Ground Switch Output Positive Supply - Voltage Input Name and Function SHUT-DOWN Control (VCC=ON GND=Shutdown 2/11 ST735S/ST735T ORDERING CODES TYPE ST735S ST735T DIP-8 ST735SCN ST735TCN SO-8 ST735SCD ST735TCD SO-8 (T&R) ST735SCD-TR ST735TCD-TR TYPICAL APPLICATION CIRCUIT NOTE: 1) All capacitors are X7R ceramic 2) C5 can be omitted if are used higher values for the input and output capacitors (suggested C2=47F, C1=100F). 3) R1 and R2 must be placed is ST735T applications only. Their values are calculated by the following formula R2=(|VOUT|/VREF)xR1. For R1 can be chosen any value between 2k and 20k APPLICATION CIRCUIT To achieve the best performances from switching power supply topology, particular care to layout drawing is needed, in order to minimize EMI and obtain low noise. Moreover, jitter free operation ensures the full device functionality. Layout design proposed on demoboard helps to lower the developing time. Wire lengths must be minimized, PRINTED DEMOBOARD (not in scale) filter and bypass capacitors must be low ESR type, placed as close as possible to the integrated circuit. The 4.7F (or 6.8F) inductor must be chosen built on a core, taking care that saturation current should be higher than the peak LX switch current. See the Peak Inductor Current vs Output Current graph. 3/11 ST735S/ST735T ELECTRICAL CHARACTERISTICS OF ST735S (Refer to test circuit, VIN=5V, CIN = 4.7F, COUT = 10F all X7R ceramic, L = 4.7H (Note1) , IOUT=0mA, Tamb = -40 to 125C, unless otherwise specified. Typical value are referred at Tamb= 25C) Symbol VIN VOUT Parameter Input Voltage Output Voltage VIN = 4.5V to 6.2V IOUT = 0 to 200mA Tamb= -40 to 125C VIN = 4.0V to 6.2V IOUT = 0 to 175mA Tamb= -40 to 125C IOUT Output Current VIN = 4.5V to 6.2V TJ= 0 to 125C VIN = 4.5V to 6.2V IOUT = 0 to 175mA Tamb= -40 to 125C VIN = 4.0V ISUPPLY ISC IPEAK VLO VOUT VOUT VREF VREF RDSON ILEAK ISH VIL VIH fOSC RCC Supply Current Short Circuit Current LX Max Peak Current Undervoltage Lock-out Line Regulation Load Regulation Reference Voltage Reference Drift LX ON Voltage LX Leakage Current Shutdown Pin Current Shutdown Input Low Threshold Shutdown Input High Threshold Maximum Oscillator Frequency Efficency Compensation Pin Impedance on CC Pin VDS = 10V VIN = 4.0V to 6.2V IOUT = 0 to 200mA Tamb= 25C (Note 3) Tamb= -40 to 125C ISTANDBY Standby Current VSHDN = 0V VIN = 5V (Note 2) VOUT = -5V Includes Switch Current Test Conditions Min. 4 -5.25 -5.25 200 175 175 0.8 1 0.9 1.5 3.5 0.1 0.003 1.225 50 0.5 1 1 0.25 2 300 IOUT = 100mA 72 7.5 4 1.6 10 -5 -5 275 Typ. Max. 6.2 -4.75 -4.75 Unit V V V mA mA mA mA A A A V %/V %/mA V ppm/C A A V V KHz % K Note 1: Utilize of 6.8H permits to reach higher current capability at the same operating conditions Note2: Guaranteed by design, but not tested in production Note3 : Tested at IVREF = 125A 4/11 ST735S/ST735T ELECTRICAL CHARACTERISTICS OF ST735T (Refer to test circuit, VIN=5V, CIN = 4.7F, COUT = 10F all X7R ceramic, L = 4.7H (Note1) , IOUT=0mA, VO adjusted to -5V, Tamb = -40 to 125C, unless otherwise specified. Typical value are referred at Tamb= 25C) Symbol VIN VO Parameter Input Voltage Output Voltage VIN = 4.5V to 6.2V IOUT = 0 to 200mA Tamb= -40 to 125C VIN = 4.0V to 6.2V IOUT = 0 to 175mA Tamb= -40 to 125C IO Output Current VIN = 4.5V to 6.2V Tamb= 0 to 125C VIN = 4.5V to 6.2V IOUT = 0 to 175mA Tamb= -40 to 125C VIN = 4.0V ISUPPLY ISC IPEAK VLO VOUT VOUT VREF VREF RDSON ILEAK ISH VIL VIH fOSC RCC Supply Current Short Circuit Current LX Max Peak Current Undervoltage Lock-out Line Regulation Load Regulation Reference Voltage Reference Drift LX ON Voltage LX Leakage Current Shutdown Pin Current Shutdown Input Low Threshold Shutdown Input High Threshold Maximum Oscillator Frequency Efficency Compensation Pin Impedance on CC Pin VDS = 10V VIN = 4.0V to 6.2V IOUT = 0 to 200mA Tamb= 25C (Note 3) Tamb= -40 to 125C ISTANDBY Standby Current VSHDN = 0V VIN = 5V (Note 2) VOUT = -5V Includes Switch Current Test Conditions Min. 3.5 -5.25 -5.25 200 175 175 0.8 1 0.9 1.5 3.5 0.1 0.003 1.225 50 0.5 1 1 0.25 2 300 IOUT = 100mA 72 7.5 4 1.6 10 -5 -5 275 Typ. Max. 9 -4.75 -4.75 Unit V V V mA mA mA mA A A A V %/V %/mA V ppm/C A A V V KHz % K Note 1: Utilize of 6.8H permits to reach higher current capability at the same operating conditions Note2: Guaranteed by design, but not tested in production Note3 : Tested at IVREF = 125A 5/11 ST735S/ST735T TYPICAL CHARACTERISTICS (Referred to typical application circuit, Tamb=25C unless otherwise specified) Figure 1 : Output Voltage vs Temperature Figure 4 : Efficency vs Ouput Current Figure 2 : Reference Voltage vs Temperature Figure 5 : Efficency vs Low Ouput Current Figure 3 : Efficency vs Temperature Figure 6 : Supply Current vs Temperature 6/11 ST735S/ST735T Figure 7 : Supply Current vs Input Voltage for ST735S Figure 10 : Peack Inductor vs Output Current Figure 8 : Supply Current vs Input Voltage for ST734T Figure 11 : Switch Current Limit vs Soft Start Voltage Figure 9 : Shutdown Threshold vs Temperature Figure 12 : Oscillator Frequency Vs Temperature 7/11 ST735S/ST735T Figure 13 : LX On Resistance vs Temperature Figure 16 : Load Transient VI=5V, I O=20mA to 200mA, CI = 4.7F, CO=100F, tf=1s Figure 14 : LX On Resistance vs Input Voltage Figure 17 : Load Transient VI=5V, I O=20mA to 200mA, CI = 4.7F, CO=100F, tr=1s Figure 15 : Load Transient Figure 18 : Switching Waveform VI=5V, I O=20mA to 200mA, CI = 4.7F, CO=100F, tr=tf=1s VI=5V, I O=100mA 8/11 ST735S/ST735T Plastic DIP-8 MECHANICAL DATA mm. DIM. MIN. A a1 B B1 b b1 D E e e3 e4 F I L Z 0.44 3.3 1.6 0.017 8.8 2.54 7.62 7.62 7.1 4.8 0.130 0.063 0.38 0.7 1.39 0.91 0.5 0.5 9.8 0.346 0.100 0.300 0.300 0.280 0.189 0.015 1.65 1.04 TYP 3.3 0.028 0.055 0.036 0.020 0.020 0.386 0.065 0.041 MAX. MIN. TYP. 0.130 MAX. inch P001F 9/11 ST735S/ST735T SO-8 MECHANICAL DATA DIM. A a1 a2 a3 b b1 C c1 D E e e3 F L M S 3.8 0.4 4.8 5.8 1.27 3.81 4.0 1.27 0.6 8 (max.) 0.149 0.015 5.0 6.2 0.65 0.35 0.19 0.25 0.1 mm. MIN. TYP MAX. 1.75 0.25 1.65 0.85 0.48 0.25 0.5 45 (typ.) 0.189 0.228 0.050 0.150 0.157 0.050 0.023 0.196 0.244 0.025 0.013 0.007 0.010 0.003 MIN. inch TYP. MAX. 0.068 0.009 0.064 0.033 0.018 0.010 0.019 0016023 10/11 ST735S/ST735T Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics. (c) The ST logo is a registered trademark of STMicroelectronics (c) 2002 STMicroelectronics - Printed in Italy - All Rights Reserved STMicroelectronics GROUP OF COMPANIES Australia - Brazil - Canada - China - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco Singapore - Spain - Sweden - Switzerland - United Kingdom - United States. (c) http://www.st.com 11/11 |
Price & Availability of ST735TCD-TR
 |
|
|
|
|
All Rights Reserved © IC-ON-LINE 2003 - 2022 |
| [Add Bookmark] [Contact Us] [Link exchange] [Privacy policy] |
|
Mirror Sites : [www.datasheet.hk]
[www.maxim4u.com] [www.ic-on-line.cn]
[www.ic-on-line.com] [www.ic-on-line.net]
[www.alldatasheet.com.cn]
[www.gdcy.com]
[www.gdcy.net] |