TC110. PFM/PWM Step-Up DC/DC Controller. Features. General Description. Applications. Functional Block Diagram. Device Selection Table



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PFM/PWM Step-Up DC/DC Controller TC110 Features Assured Start-up at 0.9V 50µA (Typ) Supply Current (f OSC = 100kHz) 300mA Output Current @ V IN 2.7V 0.5µA Shutdown Mode 100kHz and 300kHz Switching Frequency Options Programmable Soft-Start 84% Typical Efficiency Small Package: 5-Pin SOT-23A Applications Palmtops Battery-Operated Systems Positive LCD Bias Generators Portable Communicators Device Selection Table Part Number Output Voltage (V)* Package Osc. Freq. (khz) Operating Temp. Range TC110501ECT 5.0 5-Pin SOT-23A 100-40 Cto+85 C TC110331ECT 3.3 5-Pin SOT-23A 100-40 Cto+85 C TC110301ECT 3.0 5-Pin SOT-23A 100-40 Cto+85 C TC110503ECT 5.0 5-Pin SOT-23A 300-40 Cto+85 C TC110333ECT 3.3 5-Pin SOT-23A 300-40 Cto+85 C TC110303ECT 3.0 5-Pin SOT-23A 300-40 Cto+85 C General Description The TC110 is a step-up (Boost) switching controller that furnishes output currents of up to 300mA while delivering a typical efficiency of 84%. The TC110 normally operates in pulse width modulation mode (PWM), but automatically switches to pulse frequency modulation (PFM) at low output loads for greater efficiency. Supply current draw for the 100kHz version is typically only 50µA, and is reduced to less than 0.5µA when the SHDN input is brought low. Regulator operation is suspended during shutdown. The TC110 accepts input voltages from 2.0V to 10.0V, with a guaranteed start-up voltage of 0.9V. The TC110 is available in a small 5-Pin SOT-23A package, occupies minimum board space and uses small external components (the 300kHz version allows for less than 5mm surface-mount magnetics). Functional Block Diagram + Battery 3V 5 4 EXT 10µF TC110 V DD 1 2 3 + GND SHDN/SS 47µH D1 IN5817 Si9410DY 47µF Tantalum + *Other output voltages are available. Please contact Microchip Technology Inc. for details. Package Type 5-Pin SOT-23A R C 3V to 5V Supply OFF ON *RC Optional EXT GND 5 4 TC110 1 2 3 V DD SHDN/SS NOTE: 5-Pin SOT-23A is equivalent to the EIAJ SC-74A 2002 Microchip Technology Inc. DS21355B-page 1

1.0 ELECTRICAL CHARACTERISTICS Absolute Maximum Ratings* Voltage on V DD,, SHDN Pins... -0.3V to +12V EXT Output Current... ±100mA pk Voltage on EXT Pin...-0.3V to V DD +0.3V Power Dissipation...150mW Operating Temperature Range...-40 C to +85 C Storage Temperature Range...-40 C to +125 C *Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions above those indicated in the operation sections of the specifications is not implied. Exposure to Absolute Maximum Rating conditions for extended periods may affect device reliability. TC110 ELECTRICAL SPECIFICATIONS Electrical Characteristics: Note 1, V IN =0.6xV R,V DD =,T A =25 C, unless otherwise noted. Symbol Parameter Min Typ Max Units Test Conditions V DD Operating Supply Voltage 2.0 10.0 V Note 2 V START Start-Up Supply Voltage 0.9 V I OUT =1mA V HOLD-UP Oscillator Hold-Up Voltage 0.7 V I OUT =1mA I DD Boost Mode Supply Current I STBY Standby Supply Current 120 130 180 50 50 70 20 20 22 11 11 11 190 200 280 90 100 120 34 35 38 20 20 22 µa = SHDN = (0.95 x V R ); f OSC =300kHz;V R =3.0V V R =3.3V V R =5.0V f OSC = 100kHz; V R =3.0V V R =3.3V V R =5.0V µa = SHDN =(V R +0.5V);f OSC =300kHz;V R =3.0V V R =3.3V V R =5.0V f OSC = 100kHz; V R =3.0V V R =3.3V V R =5.0V ISHDN Shutdown Supply Current 0.05 0.5 µa SHDN =GND,V O =(V R x0.95) f OSC Oscillator Frequency 255 85 Output Voltage V R x0.975 DTYMAX Maximum Duty Cycle (PWM Mode) 300 100 V R 345 115 V R x1.025 khz = SHDN = (0.95 x V R ); f OSC =300kHz f OSC = 100kHz V Note 3 92 % = SHDN =0.95xV R DTYPFM Duty Cycle (PFM Mode) 15 25 35 % I OUT =0mA V IH SHDN Input Logic High 0.65 V =(V R x0.95) V IL SHDN Input Logic Low 0.20 V =(V R x0.95) REXTH EXT ON Resistance to V DD REXTL EXT ON Resistance to GND 32 29 20 20 19 13 47 43 29 30 27 19 η Efficiency 84 % Note 1: V R =3.0V,I OUT =120mA V R =3.3V,I OUT =130mA V R =5.0V,I OUT =200mA 2: See Application Notes Operating Mode description for clarification. 3: V R is the factory output voltage setting. Ω Ω = SHDN =(V R x0.95);v R =3.0V V R =3.3V V EXT =( 0.4V) V R =5.0V = SHDN =(V R x0.95);v R =3.0V V R =3.3V V EXT =0.4V V R =5.0V DS21355B-page 2 2002 Microchip Technology Inc.

2.0 PIN DESCRIPTIONS ThedescriptionsofthepinsarelistedinTable2-1. TABLE 2-1: Pin No. (5-Pin SOT-23A) PIN FUNCTION TABLE Symbol Description 1 Internal device power and voltage sense input. This dual function input provides both feedback voltage sensing and internal chip power. It should be connected to the regulator output. (See Section 4.0, Applications). 2 V DD Power supply voltage input. 3 SHDN/SS Shutdown input. A logic low on this input suspends device operation and supply current is reducedtolessthan0.5µa. The device resumes normal operation when SHDN is again brought high. An RC circuit connected to this input also determines the soft-start time. 4 GND Ground terminal. 5 EXT External switch transistor drive complimentary output. This pin drives the external switching transistor. It may be connected to the base of the external bipolar transistor or gate of the external N-channel MOSFET. (See Section 4.0, Applications). 2002 Microchip Technology Inc. DS21355B-page 3

3.0 DETAILED DESCRIPTION The TC110 is a PFM/PWM step-up DC/DC controller for use in systems operating from two or more cells, or in low voltage, line-powered applications. It uses PWM as the primary modulation scheme, but automatically converts to PFM at output duty cycles less than approximately 25%. The conversion to PFM provides reduced supply current, and therefore higher operating efficiency at low loads. The TC110 uses an external switching transistor, allowing construction of switching regulators with maximum output currents of 300mA. The TC110 consumes only 70µA, typical, of supply current and can be placed in a 0.5µA shutdown mode by bringing the shutdown input (SHDN) low. The regulator remains disabled while in shutdown mode, and normal operation resumes when SHDN is brought high. Other features include start-up at V IN = 0.9V and an externally programmable soft start time. 3.1 Operating Mode The TC110 is powered by the voltage present on the V DD input. The applications circuits of Figure 3-1 and Figure 3-2 show operation in the bootstrapped and non-bootstrapped modes. In bootstrapped mode, the TC110 is powered from the output (start-up voltage is supplied by V IN through the inductor and Schottky diode while Q1 is off). In bootstrapped mode, the switching transistor is turned on harder because its gate voltage is higher (due to the boost action of the regulator), resulting in higher output current capacity. The TC110 is powered from the input supply in the nonbootstrapped mode. In this mode, the supply current to the TC110 is minimized. However, the drive applied to the gate of the switching transistor swings from the input supply level to ground, so the transistor s ON resistance increases at low input voltages. Overall efficiency is increased since supply current is reduced, and less energy is consumed charging and discharging the gate of the MOSFET. While the TC110 is guaranteed to start up at 0.9V the device performs to specifications at 2.0V and higher. 3.2 Low Power Shutdown Mode The TC110 enters a low power shutdown mode when SHDN is brought low. While in shutdown, the oscillator is disabled and the output switch (internal or external) is shut off. Normal regulator operation resumes when SHDN is brought high. SHDN maybetiedtotheinput supply if not used. Note: 3.3 Soft Start Because the TC110 uses an external diode, a leakage path between the input voltage and the output node (through the inductor and diode) exists while the regulator is in shutdown. Care must be taken in system design to assure the input supply is isolated from the load during shutdown. Soft start allows the output voltage to gradually ramp from 0V to rated output value during start-up. This action minimizes (or eliminates) overshoot, and in general, reduces stress on circuit components. Figure 3-3 shows the circuit required to implement soft start (values of 470K and 0.1µF for R SS and C SS, respectively, are adequate for most applications). 3.4 Input Bypass Capacitors Using an input bypass capacitor reduces peak current transients drawn from the input supply and reduces the switching noise generated by the regulator. The source impedance of the input supply determines the size of the capacitor that should be used. DS21355B-page 4 2002 Microchip Technology Inc.

FIGURE 3-1: BOOTSTRAPPED OPERATION 5 4 L1 100µH D1 IN5817 n MTP3055EL C2 47µF EXT TC110XX GND + C1 33µF V IN V DD SHDN 1 2 3 OFF ON FIGURE 3-2: NON-BOOTSTRAPPED OPERATION L1 100µH D1 IN5817 5 4 n MTP3055EL C2 47µF EXT GND TC110XX V DD SHDN 1 2 3 + V IN C1 33µF OFF ON FIGURE 3-3: SOFT START/SHUTDOWN CIRCUIT TC110XX SHDN/SS 3 TC110XX SHDN/SS 3 R SS 470K V IN R SS 470K SHDN C SS 0.1µF C SS 0.1µF Shutdown Not Used Shutdown Used 2002 Microchip Technology Inc. DS21355B-page 5

3.5 Output Capacitor The effective series resistance of the output capacitor directly affects the amplitude of the output voltage ripple. (The product of the peak inductor current and the ESR determines output ripple amplitude.) Therefore, a capacitor with the lowest possible ESR should be selected. Smaller capacitors are acceptable for light loads or in applications where ripple is not a concern. The Sprague 595D series of tantalum capacitors are among the smallest of all low ESR surface mount capacitors available. Table 4-1 lists suggested components and suppliers. 3.6 Inductor Selection Selecting the proper inductor value is a trade-off between physical size and power conversion requirements. Lower value inductors cost less, but result in higher ripple current and core losses. They are also more prone to saturate since the coil current ramps faster and could overshoot the desired peak value. This not only reduces efficiency, but could also cause the current rating of the external components to be exceeded. Larger inductor values reduce both ripple current and core losses, but are larger in physical size and tend to increase the start-up time slightly. A 22µH inductor is recommended for the 300kHz versions and a 47µH inductor is recommended for the 100kHz versions. Inductors with a ferrite core (or equivalent) are also recommended. For highest efficiency, use inductors with a low DC resistance (less than 20 mω). The inductor value directly affects the output ripple voltage. Equation 3-3 is derived as shown below, and can be used to calculate an inductor value, given the required output ripple voltage and output capacitor series resistance: EQUATION 3-1: where ESR is the equivalent series resistance of the output filter capacitor, and V RIPPLE is in volts. Expressing di in terms of switch ON resistance and time: EQUATION 3-2: Solving for L: EQUATION 3-3: V RIPPLE ESR(di) V RIPPLE ESR [(V IN V SW )t ON ] L L ESR [(V IN V SW )t ON ] V RIPPLE Care must be taken to ensure the inductor can handle peak switching currents, which can be several times load currents. Exceeding rated peak current will result in core saturation and loss of inductance. The inductor should be selected to withstand currents greater than I PK (Equation 3-10) without saturating. Calculating the peak inductor current is straightforward. Inductor current consists of an AC (sawtooth) current centered on an average DC current (i.e., input current). Equation 3-6 calculates the average DC current. Note that minimum input voltage and maximum load current values should be used: EQUATION 3-4: Input Power Re-writing in terms of input and output currents and voltages: EQUATION 3-5: (V INMIN )(I INMAX )= Solving for input curent: EQUATION 3-6: I INMAX = The sawtooth current is centered on the DC current level; swinging equally above and below the DC current calculated in Equation 3-6. The peak inductor current is the sum of the DC current plus half the AC current. Note that minimum input voltage should be used when calculating the AC inductor current (Equation 3-9). EQUATION 3-7: EQUATION 3-8: EQUATION 3-9: di = where: V SW =V CESAT oftheswitch(noteifacmos switch is used substitute V CESAT for r DSON xi IN ) Combining the DC current calculated in Equation 3-6, with half the peak AC current calculated in Equation 3-9, the peak inductor current is given by: EQUATION 3-10: = Output Power Efficiency (MAX ) (I OUTMAX ) Efficiency (MAX )(I OUTMAX ) (Efficiency)(V INMAX ) V di = L(di) dt = V(dt) dt [(V INMIN V SW )t ON ] L I PK = I INMAX +0.5(di) DS21355B-page 6 2002 Microchip Technology Inc.

3.7 Output Diode For best results, use a Schottky diode such as the MA735, 1N5817, MBR0520L or equivalent. Connect the diode between the FB (or SENSE) input as close to the IC as possible. Do not use ordinary rectifier diodes since the higher threshold voltages reduce efficiency. 3.8 External Switching Transistor Selection The EXT output is designed to directly drive an N-channel MOSFET or NPN bipolar transistor. N- channel MOSFETs afford the highest efficiency because they do not draw continuous gate drive current, but are typically more expensive than bipolar transistors. If using an N-channel MOSFET, the gate should be connected directly to the EXT output as shown in Figure 3-1 and Figure 3-1. EXT is a complimentary output with a maximum ON resistances of 43Ω to V DD when high and 27Ω to ground when low. Peak currents should be kept below 10mA. When selecting an N-channel MOSFET, there are three important parameters to consider: total gate charge (Qg); ON resistance (r DSON ) and reverse transfer capacitance (CRSS). Qg is a measure of the total gate capacitance that will ultimately load the EXT output. Too high a Qg can reduce the slew rate of the EXT output sufficiently to grossly lower operating efficiency. Transistors with typical Qg data sheet values of 50nC or less can be used. For example, the Si9410DY has a Qg (typ) of 17nC @ V GS = 5V. This equates to a gate current of: I GATEMAX =f MAX x Qg = 115kHz x 17nC = 2mA The two most significant losses in the N-channel MOSFET are switching loss and I 2 R loss. To minimize these, a transistor with low r DSON and low CRSS should be used. Bipolar NPN transistors can be used, but care must be taken when determining base current drive. Too little current will not fully turn the transistor on, and result in unstable regulator operation and low efficiency. Too high a base drive causes excessive power dissipation in the transistor and increase switching time due to over-saturation. For peak efficiency, make R B as large as possible, but still guaranteeing the switching transistor is completely saturated when the minimum value of h FE is used. 3.9 Board Layout Guidelines As with all inductive switching regulators, the TC110 generates fast switching waveforms which radiate noise. Interconnecting lead lengths should be minimized to keep stray capacitance, trace resistance and radiated noise as low as possible. In addition, the GND pin, input bypass capacitor and output filter capacitor ground leads should be connected to a single point. The input capacitor should be placed as close to power and ground pins of the TC110 as possible. 2002 Microchip Technology Inc. DS21355B-page 7

4.0 APPLICATIONS 4.1 Circuit Examples Figure 4-1 shows a TC110 operating as a 100kHz bootstrapped regulator with soft start. This circuit uses an NPN switching transistor (Zetex FZT690B) that has an h FE of 400 and V CESAT of 100 mv at I C = 1A. Other high beta transistors can be used, but the values of R B and C B may need adjustment if h FE is significantly different from that of the FZT690B. Figure 4-2 and Figure 4-3 both utilize an N-channel switching transistor (Silconix Si9410DY). This transistor is a member of the Littlefoot TM family of small outline MOSFETs. The circuit of Figure 4-2 operates in bootstrapped mode, while the circuit of Figure 4-3 operates in non-bootstrapped mode. TABLE 4-1: SUGGESTED COMPONENTS AND SUPPLIERS Type Inductors Capacitors Diodes Transistors Surface Mount Sumida CD54 Series (300kHz) CD75 (100kHz) Matsuo 267 Series Nihon EC10 Series N-channel Silconix Si9410DY Through-Hole Coiltronics CTX Series Sumida RCH855 Series RCH110 Series Renco RL1284-12 Sprague 595D Series Nichicon F93 Series Sanyo OS-CON Series Nichicon PL Series Matsushita MA735 Series ON Semiconductor 1N5817-1N5822 ON Semiconductor MTP3055EL MTD20N03 NPN Zetex ZTX694B DS21355B-page 8 2002 Microchip Technology Inc.

FIGURE 4-1: 100kHz BOOTSTRAPPED REGULATOR WITH SOFT START USING A BIPOLAR TRANSISTOR V IN C IN 10µF/16V L1 47µH Sumida CD75 CB 10nF Ceramic D1 Matsushita MA737 5 EXT RB 1K TC110301 4 GND Q1 FZT690BCT C OUT 47µF, 10V Tant. V C DD SHDN/SS SS 0.1µF 1 2 3 Ceramic R SS 470K SHUTDOWN (Optional) FIGURE 4-2: 300kHz BOOTSTRAPPED, N-CHANNEL TRANSISTOR V IN C IN 10µF/16V L1 22µH Sumida CD54 5 4 D1 ON Semiconductor MBR0520L Q1 Silconix Si9410DY C OUT 47µF, 16V Tant. EXT GND TC110303 V DD SHDN/SS 1 2 3 FIGURE 4-3: 300kHz NON-BOOTSTRAPPED, N-CHANNEL TRANSISTOR V IN C IN 10µF/16V L1 22µH Sumida CD54 5 4 D1 ON Semiconductor MBR0520L Q1 Silconix Si9410DY C OUT 47µF, 16V Tant. EXT GND TC110303 V DD SHDN/SS 1 2 3 2002 Microchip Technology Inc. DS21355B-page 9

5.0 TYPICAL CHARACTERISTICS (Unless Otherwise Specified, All Parts Are Measured At Temperature = 25 C) Note: The graphs and tables provided following this note are a statistical summary based on a limited number of samples and are provided for informational purposes only. The performance characteristics listed herein are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified operating range (e.g., outside specified power supply range) and therefore outside the warranted range. Output Voltage vs. Output Current TC110 (300kHz, 3.3V) L = 22µH, CL = 94µF (Tantalum) 3.5 100 Efficiency vs. Output Current TC110 (300kHz, 3.3V) L = 22µH, CL = 94µF (Tantalum) OUTPUT VOLTAGE ( ) (V) 3.4 3.3 3.2 3.1 V IN = 0.9V 1.2V 1.8V 1.5V 2.0V 2.7V EFFICIENCY (%) 80 2.7V 60 40 20 V IN = 0.9V 1.2V 1.5V 2.0V 1.8V 3.0 0.1 1 10 100 1000 OUTPUT CURRENT I OUT (ma) 0 0.1 1 10 100 1000 OUTPUT CURRENT I OUT (ma) DS21355B-page 10 2002 Microchip Technology Inc.

6.0 PACKAGING INFORMATION 6.1 Package Marking Information 1 represents product classification; TC110 = M 2 represents first integer of voltage and frequency Symbol (100kHz) Symbol (300kHz) Voltage B 1 1. C 2 2. D 3 3. E 4 4. F 5 5. H 6 6. 3 represents first decimal of voltage and frequency Symbol (100kHz) Symbol (300kHz) Voltage 0 A.0 1 B.1 2 C.2 3 D.3 4 E.4 5 F.5 6 H.6 7 K.7 8 L.8 9 M.9 4 represents production lot ID code 2002 Microchip Technology Inc. DS21355B-page 11

6.2 Taping Form Component Taping Orientation for 5-Pin SOT-23A (EIAJ SC-74A) Devices Device Marking User Direction of Feed W PIN 1 P Standard Reel Component Orientation TR Suffix Device (Mark Right Side Up) Carrier Tape, Number of Components Per Reel and Reel Size Package Carrier Width (W) Pitch (P) Part Per Full Reel Reel Size 5-Pin SOT-23A 8 mm 4 mm 3000 7 in 6.3 Package Dimensions SOT-23A-5.075 (1.90) REF..122 (3.10).098 (2.50).071 (1.80).059 (1.50).020 (0.50).012 (0.30) PIN 1.037 (0.95) REF..122 (3.10).106 (2.70).057 (1.45).035 (0.90).006 (0.15).000 (0.00) 10 MAX..010 (0.25).004 (0.09).024 (0.60).004 (0.10) Dimensions: inches (mm) DS21355B-page 12 2002 Microchip Technology Inc.

Sales and Support Data Sheets Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following: 1. Your local Microchip sales office 2. The Microchip Corporate Literature Center U.S. FAX: (480) 792-7277 3. The Microchip Worldwide Site (www.microchip.com) Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using. New Customer Notification System Register on our web site (www.microchip.com/cn) to receive the most current information on our products. 2002 Microchip Technology Inc. DS21355B-page13

NOTES: DS21355B-page14 2002 Microchip Technology Inc.

Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip s products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, under any intellectual property rights. Trademarks The Microchip name and logo, the Microchip logo, FilterLab, KEELOQ, microid, MPLAB, PIC, PICmicro, PICMASTER, PICSTART, PRO MATE, SEEVAL and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. dspic, ECONOMONITOR, FanSense, FlexROM, fuzzylab, In-Circuit Serial Programming, ICSP, ICEPIC, microport, Migratable Memory, MPASM, MPLIB, MPLINK, MPSIM, MXDEV, MXLAB, PICC, PICDEM, PICDEM.net, rfpic, Select Mode and Total Endurance are trademarks of Microchip Technology Incorporated in the U.S.A. Serialized Quick Turn Programming (SQTP) is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. 2002, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. Printed on recycled paper. Microchip received QS-9000 quality system certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona in July 1999 and Mountain View, California in March 2002. The Company s quality system processes and procedures are QS-9000 compliant for its PICmicro 8-bit MCUs, KEELOQ code hopping devices, Serial EEPROMs, microperipherals, non-volatile memory and analog products. In addition, Microchip s quality system for the design and manufacture of development systems is ISO 9001 certified. 2002 Microchip Technology Inc. DS21355B-page 15

WORLDWIDE SALES AND SERVICE AMERICAS Corporate Office 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7200 Fax: 480-792-7277 Technical Support: 480-792-7627 Web Address: http://www.microchip.com Rocky Mountain 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7966 Fax: 480-792-7456 Atlanta 500 Sugar Mill Road, Suite 200B Atlanta, GA 30350 Tel: 770-640-0034 Fax: 770-640-0307 Boston 2 Lan Drive, Suite 120 Westford, MA 01886 Tel: 978-692-3848 Fax: 978-692-3821 Chicago 333 Pierce Road, Suite 180 Itasca, IL 60143 Tel: 630-285-0071 Fax: 630-285-0075 Dallas 4570 Westgrove Drive, Suite 160 Addison, TX 75001 Tel: 972-818-7423 Fax: 972-818-2924 Detroit Tri-Atria Office Building 32255 Northwestern Highway, Suite 190 Farmington Hills, MI 48334 Tel: 248-538-2250 Fax: 248-538-2260 Kokomo 2767 S. Albright Road Kokomo, Indiana 46902 Tel: 765-864-8360 Fax: 765-864-8387 Los Angeles 18201 Von Karman, Suite 1090 Irvine, CA 92612 Tel: 949-263-1888 Fax: 949-263-1338 New York 150 Motor Parkway, Suite 202 Hauppauge, NY 11788 Tel: 631-273-5305 Fax: 631-273-5335 San Jose Microchip Technology Inc. 2107 North First Street, Suite 590 San Jose, CA 95131 Tel: 408-436-7950 Fax: 408-436-7955 Toronto 6285 Northam Drive, Suite 108 Mississauga, Ontario L4V 1X5, Canada Tel: 905-673-0699 Fax: 905-673-6509 ASIA/PACIFIC Australia Microchip Technology Australia Pty Ltd Suite 22, 41 Rawson Street Epping 2121, NSW Australia Tel: 61-2-9868-6733 Fax: 61-2-9868-6755 China - Beijing Microchip Technology Consulting (Shanghai) Co., Ltd., Beijing Liaison Office Unit 915 Bei Hai Wan Tai Bldg. No. 6 Chaoyangmen Beidajie Beijing, 100027, No. China Tel: 86-10-85282100 Fax: 86-10-85282104 China - Chengdu Microchip Technology Consulting (Shanghai) Co., Ltd., Chengdu Liaison Office Rm. 2401, 24th Floor, Ming Xing Financial Tower No. 88 TIDU Street Chengdu 610016, China Tel: 86-28-86766200 Fax: 86-28-86766599 China - Fuzhou Microchip Technology Consulting (Shanghai) Co., Ltd., Fuzhou Liaison Office Unit 28F, World Trade Plaza No. 71 Wusi Road Fuzhou 350001, China Tel: 86-591-7503506 Fax: 86-591-7503521 China - Shanghai Microchip Technology Consulting (Shanghai) Co., Ltd. Room 701, Bldg. B Far East International Plaza No. 317 Xian Xia Road Shanghai, 200051 Tel: 86-21-6275-5700 Fax: 86-21-6275-5060 China - Shenzhen Microchip Technology Consulting (Shanghai) Co., Ltd., Shenzhen Liaison Office Rm. 1315, 13/F, Shenzhen Kerry Centre, Renminnan Lu Shenzhen 518001, China Tel: 86-755-2350361 Fax: 86-755-2366086 China - Hong Kong SAR Microchip Technology Hongkong Ltd. Unit 901-6, Tower 2, Metroplaza 223 Hing Fong Road Kwai Fong, N.T., Hong Kong Tel: 852-2401-1200 Fax: 852-2401-3431 India Microchip Technology Inc. India Liaison Office Divyasree Chambers 1 Floor, Wing A (A3/A4) No. 11, O Shaugnessey Road Bangalore, 560 025, India Tel: 91-80-2290061 Fax: 91-80-2290062 Japan Microchip Technology Japan K.K. Benex S-1 6F 3-18-20, Shinyokohama Kohoku-Ku, Yokohama-shi Kanagawa, 222-0033, Japan Tel: 81-45-471-6166 Fax: 81-45-471-6122 Korea Microchip Technology Korea 168-1, Youngbo Bldg. 3 Floor Samsung-Dong, Kangnam-Ku Seoul, Korea 135-882 Tel: 82-2-554-7200 Fax: 82-2-558-5934 Singapore Microchip Technology Singapore Pte Ltd. 200 Middle Road #07-02 Prime Centre Singapore, 188980 Tel: 65-6334-8870 Fax: 65-6334-8850 Taiwan Microchip Technology Taiwan 11F-3, No. 207 Tung Hua North Road Taipei, 105, Taiwan Tel: 886-2-2717-7175 Fax: 886-2-2545-0139 EUROPE Denmark Microchip Technology Nordic ApS Regus Business Centre Lautrup hoj 1-3 Ballerup DK-2750 Denmark Tel: 45 4420 9895 Fax: 45 4420 9910 France Microchip Technology SARL Parc d Activite du Moulin de Massy 43 Rue du Saule Trapu Batiment A - ler Etage 91300 Massy, France Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79 Germany Microchip Technology GmbH Gustav-Heinemann Ring 125 D-81739 Munich, Germany Tel: 49-89-627-144 0 Fax: 49-89-627-144-44 Italy Microchip Technology SRL Centro Direzionale Colleoni Palazzo Taurus 1 V. Le Colleoni 1 20041 Agrate Brianza Milan, Italy Tel: 39-039-65791-1 Fax: 39-039-6899883 United Kingdom Microchip Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5869 Fax: 44-118 921-5820 05/01/02 DS21355B-page 16 2002 Microchip Technology Inc.