ST735CD

ST735 -5V INVERTING, NEGATIVE OUTPUT CURRENT-MODE PWM REGULATOR ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ CONVERTS +4.0V TO + 6.2V INPUT TO -5V OUTPUT 1W GUARANTEED OUTPUT POWER 75% TYPICAL EFFICIENCY 0.8mA QUIESCENT CURRENT 10µA SHUTDOWN MODE 160KHZ FIXED FREQUENCY OSCILLATOR CURRENT MODE PWM CONVERTER LOW NOISE AND JITTER SOFT START SIMPLE APPLICATION CIRCUIT UNDERVOLTAGE LOCKOUT DESCRIPTION The ST735 is a Bi-CMOS, inverting switch mode DC-DC regulator with internal Power MOSFET's that generates a fixed -5V output voltage from a 4V to 6.2V input voltage; is guaranteed an output current of 200mA for inputs greater than 4.5V. The quiescent current for this device is typically of 0.8mA and, in shutdown mode it is reduced to 10µA. ) s ( ct SCHEMATIC DIAGRAM DIP-8 SO-8 ) s t( These power-conserving features, along with high efficiency and applications circuits, that lend itself to minaturization, make the ST735 excellent in a broad range of on-card, HDD and portable equipment applications. The ST735 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 160KHz, allowing for easy noise filtering. The regulator in production is tested to guarantee an output accuracy within ±5% over all specified conditions. c u d e t le o r P o s b O - u d o r P e t e l o s b O August 2002 1/9 ST735 ABSOLUTE MAXIMUM RATINGS Symbol VIN SHDN Parameter DC Input Voltage (VIN to GND) Shutdown Voltage (SHDN to GND) VLX Switch Voltage (Lx to VIN) VFB Feedback Voltage (VOUT to GND) VOUT Value -0.3 to +7 V -0.3 to V++0.3 V -12.5 to +0.3 V -11 to +0.3 V Output Voltage (VOUT to GND) Other Input Voltage (SS, CC to GND) -11 to +0.3 V -0.3 to V++0.3 V Peack Switch Current ILX Ptot Power Dissipation at Tj = 70°C Unit DIP-8 SO-8 2 A 725 470 mW Tstg Storage Temperature Range -55 to +150 °C Top Operating Junction Temperature Range -40 to +125 °C Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. THERMAL DATA Symbol Rthj-case Parameter Thermal Resistance Junction-case 2 CONNECTION DIAGRAM (top view) ) s ( ct 2/9 o r P u d o 2 VREF Reference Output Voltage 3 4 5 SS CC VOUT Soft Start Compensation Input Negative Output Voltage 6 7 8 GND LX VIN Ground Switch Output Positive Supply - Voltage Input t e l o SO-8 o s b O - 1 Pin N° s b O e t le r P e PIN DESCRIPTION Symbol SHDN c u d DIP-8 Name and Function SHUT-DOWN Control (VCC=ON GND=Shutdown 8 ) s t( Unit °C/W ST735 ORDERING CODES TYPE DIP-8 SO-8 SO-8 (T&R) ST735 ST735CN ST735CD ST735CD-TR TYPICAL APPLICATION CIRCUIT c u d e t le ) s t( o r P o s b O - NOTE: 1) All capacitors are X7R ceramic 2) C5 can be omitted if are used higher values for the input and output capacitors C2=47µF, C1=100pF. ) s ( ct u d o r P e t e l o s b O 3/9 ST735 ELECTRICAL CHARACTERISTICS (Refer to test circuit, VIN=5V, CIN = 4.7µF, COUT = 10µF, L = 10µH, Tamb = -40 to 125°C, unless otherwise specified. Typical value are referred at Tamb= 25°C) Symbol VIN Parameter Test Conditions Min. Input Voltage VOUT IOUT Max. 4 Output Voltage Output Current Supply Current 6.2 V -5.25 -5 -4.75 V VIN = 4.0V to 6.2V IOUT = 0 to 175mA Tamb= -40 to 125°C -5.25 -5 -4.75 V VIN = 4.5V to 6.2V Tamb= 0 to 125°C 200 275 VIN = 4.5V to 6.2V IOUT = 0 to 175mA Tamb= -40 to 125°C 175 VOUT = -5V mA mA 175 Includes Switch Current ISTANDBY Standby Current VSHDN = 0V mA 0.8 1.6 mA 1 10 µA ISC Short Circuit Current 1.5 VLO Undervoltage Lock-out 3.5 A ∆VOUT Line Regulation VIN = 4.0V to 6.2V 0.1 Load Regulation IOUT = 0 to 200mA 0.003 Reference Voltage Tamb= 25°C (Note 1) VREF Reference Drift RDSON LX ON Voltage ILEAK LX Leakage Current ISH Shutdown Pin Current VIL Shutdown Input Low Threshold Shutdown Input High Threshold Maximum Oscillator Frequency Efficency VIH fOSC ν r P e Note1 : Tested at IVREF = 0mA t e l o s b O 4/9 VDS = 10V ct (s) IOUT = 100mA u d o Compensation Pin Impedance on CC Pin RCC r P e t le Tamb= -40 to 125°C o s b O - ) s t( 4 ∆VOUT ∆VREF Unit VIN = 4.5V to 6.2V IOUT = 0 to 200mA Tamb= -40 to 125°C VIN = 4.0V ISUPPLY Typ. uc od V %/V %/mA 1.247 V 50 ppm/°C 0.5 Ω µA 1 2 1 µA 0.25 V V 160 KHz 72 % 7.5 KΩ ST735 TYPICAL CHARACTERISTICS (Referred to typical application circuit, Tamb=25°C unless otherwise specified) Figure 1 : Output Voltage vs Temperature Figure 4 : Efficency vs Temperature c u d Figure 2 : Reference Voltage vs Temperature Figure 5 : Efficency vs Ouput Current e t le ) s ( ct u d o r P e ) s t( o r P o s b O - Figure 3 : Oscillator Frequency vs Temperature Figure 6 : Supply Current vs Temperature t e l o s b O 5/9 ST735 Figure 7 : Supply Current vs Input Voltage Figure 10 : Switch Current Limit vs Soft Start Voltage Figure 8 : Shutdown Threshold vs Temperature Figure 11 : LX On Resistance vs Temperature c u d e t le ) s ( ct u d o r P e Figure 9 : Peak Inductor Current vs Output Current t e l o s b O 6/9 ) s t( o r P o s b O - Figure 12 : LX On Resistance vs Input Voltage ST735 Plastic DIP-8 MECHANICAL DATA mm. inch DIM. MIN. TYP A MAX. MIN. 3.3 TYP. MAX. 0.130 a1 0.7 0.028 B 1.39 1.65 0.055 0.065 B1 0.91 1.04 0.036 0.041 b b1 0.5 0.38 0.020 0.5 D 0.015 0.020 9.8 0.386 E 8.8 0.346 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 F 7.1 I 4.8 L Z 0.44 1.6 ) s ( ct ro P e let 3.3 o s b O - c u d 0.017 ) s t( 0.280 0.189 0.130 0.063 u d o r P e t e l o s b O P001F 7/9 ST735 SO-8 MECHANICAL DATA mm. DIM. MIN. TYP A inch MAX. MIN. TYP. MAX. a1 1.75 0.1 0.068 0.25 a2 0.003 0.009 1.65 0.064 a3 0.65 0.85 0.025 0.033 b 0.35 0.48 0.013 0.018 b1 0.19 0.25 0.007 0.010 C 0.25 0.5 0.010 0.019 c1 45˚ (typ.) D 4.8 5.0 0.189 E 5.8 6.2 0.228 0.244 c u d e 1.27 0.050 e3 3.81 0.150 F 3.8 4.0 0.149 L 0.4 1.27 0.015 M e t le 0.6 S 8˚ (max.) ) s ( ct ) s t( 0.196 o r P 0.157 0.050 0.023 o s b O - u d o r P e t e l o s b O 0016023 8/9 ST735 c u d e t le ) s ( ct ) s t( o r P o s b O - u d o r P e t e l o s b O 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. © The ST logo is a registered trademark of STMicroelectronics © 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. © http://www.st.com 9/9