ST735 STMICROELECTRONICS | Alldatasheet

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■ 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. 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. ST735 -5V INVERTING, NEGATIVE OUTPUT CURRENT-MODE PWM REGULATOR SCHEMATIC DIAGRAM DIP-8 SO-8

Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. THERMAL DATA CONNECTION DIAGRAM (top view) PIN DESCRIPTION Symbol Parameter Value Unit VIN DC Input Voltage (VIN to GND) -0.3 to +7 V SHDN Shutdown Voltage (SHDN to GND) -0.3 to V ++0.3 V VLX Switch Voltage (Lx to VIN) -12.5 to +0.3 V VFB Feedback Voltage (VOUT to GND) - 1 1t o+ 0 . 3 V VOUT Output Voltage (VOUT to GND) - 1 1t o+ 0 . 3 V Other Input Voltage (SS, CC to GND) -0.3 to V ++0.3 V ILX Peack Switch Current 2A Ptot Power Dissipation at Tj= 70°C DIP-8 725 mWSO-8 470 Tstg Storage Temperature Range -55 to +150 °C Top Operating Junction Temperature Range -40 to +125 °C Symbol Parameter DIP-8 SO-8 Unit Rthj-case Thermal Resistance Junction-case 2 8 °C/W Pin N° Symbol Name and Function

1 SHDN SHUT-DOWN Control (V CC =ON GND=Shutdown

2V REF Reference Output Voltage

3 SS Soft Start

4 CC Compensation Input

OUT Negative Output Voltage

6 GND Ground

7 LX Switch Output

IN Positive Supply - Voltage Input

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 C2=47µF, C1=100pF. TYPE DIP-8 SO-8 SO-8 (T&R) ST735 ST735CN ST735CD ST735CD-TR

ELECTRICAL CHARACTERISTICS (Refer to test circuit, VIN=5V, CIN =4 . 7µF, COUT =1 0µF, L = 10µH, Tamb = -40 to 125°C, unless otherwise specified. Typical value are referred at Tamb = 25°C) Note1 : Tested at IVREF =0 m A Symbol Parameter Test Conditions Min. Typ. Max. Unit VIN Input Voltage 4 6.2 V VOUT Output Voltage V IN = 4.5V to 6.2V IOUT = 0 to 200mA Tamb = -40 to 125°C -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 IOUT Output Current VIN = 4.5V to 6.2V Tamb = 0 to 125°C 200 275 mA VIN = 4.5V to 6.2V IOUT = 0 to 175mA Tamb = -40 to 125°C 175 mA VIN = 4.0V V OUT = -5V 175 mA ISUPPLY Supply Current Includes Switch Current 0.8 1.6 mA ISTANDBY Standby Current V SHDN =0 V 1 1 0 µA ISC Short Circuit Current 1.5 A VLO Undervoltage Lock-out 3.5 4 V ΔVOUT Line Regulation V IN = 4.0V to 6.2V 0.1 %/V ΔV OUT Load Regulation I OUT = 0 to 200mA 0.003 %/mA VREF Reference Voltage Tamb =2 5°C (Note 1) 1.247 V ΔVREF Reference Drift Tamb = -40 to 125°C 50 ppm/°C R DSON LX ON Voltage 0.5 Ω ILEAK LX Leakage Current V DS = 10V 1 µA ISH Shutdown Pin Current 1 µA VIL Shutdown Input Low Threshold 0.25 V VIH Shutdown Input High Threshold fOSC Maximum Oscillator Frequency

160 KHz

ν Efficency I OUT = 100mA 72 % R CC Compensation Pin Impedance on CC Pin

7.5 K Ω

DIM. mm. inch A 3.3 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 0.5 0.020 b1 0.38 0.5 0.015 0.020 D 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 0.280 I 4.8 0.189 L 3.3 0.130 Z 0.44 1.6 0.017 0.063 Plastic DIP-8 MECHANICAL DATA P001F

DIM. mm. inch A 1.75 0.068 a1 0.1 0.25 0.003 0.009 a2 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 0.196 E 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 3.81 0.150 F 3.8 4.0 0.149 0.157 L 0.4 1.27 0.015 0.050 M 0.6 0.023 S ˚ (max.) SO-8 MECHANICAL DATA 0016023

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