TCA2002

TCA2002 TRIPATH | Alldatasheet

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Tripath Technology, Inc. - Technical Information 1 TCA2002 – KLi/0.95/04.06 TCA2002 STEREO CLASS-T™ AUDIO CONTROLLER USING DIGITAL POWER PROCESSING (DPP™) TECHNOLOGY GENERAL DESCRIPTION The TCA2002 is a two channel audio controller that uses Tripath’s proprietary Digital Power Processing (DPPTM) technology. When combined with switching power output stages, the TCA2002 allows the implementation of a complete Class-T audio amplifier. Class-T amplifiers offer both the audio fidelity of Class-AB and the power efficiency of Class-D amplifiers. The TCA2002 is pin compatible with the Tripath’s previous stereo controllers, the TC2000 and TC2001. The basis for Tripath controllers is a proprietary, fully scalable, feedback structure. The TCA2002 is capable of single ended or bridged operation, with single or split power supplies. When mated with the appropriate power stage, amplifiers with output powers of 25W to 1000W, or more, are possible. Both Tripath power stages as well as third party power stages, whether integrated, or discrete, can be used to make a complete, high-performance switching amplifier. Many features on the TCA2002 have been improved including increased supply range, elimination of turn-on pop, and automatic recovery from an overcurrent fault.

APPLICATIONS

¾ High End Amplifiers ¾ Professional Audio Amplifiers ¾ 5.1-Channel DVD ¾ Mini/Micro Component Systems BENEFITS ¾ High fidelity, high efficiency Class-T controller ¾ Feedback structure allows usage of unregulated power supply ¾ Analog inputs ¾ Improved Click and Pop performance ¾ Wider power supply range

FEATURES

¾ Class-T Architecture ¾ Audiophile Quality performance when mated with appropriate power circuitry ¾ Supply range configurable via external resistors ¾ Wide Dynamic Range >100dB ¾ Compatible with unregulated and regulated power supplies ¾ Break Before Make (BBM) circuitry ¾ Over voltage and Under voltage circuitry with wider supply range ¾ Fully deglitched comparators for overcurrent detection ¾ Automatic recovery from fault conditions ¾ Pin compatible with TC2000 and TC2001

Tripath Technology, Inc. - Technical Information 2 TCA2002 – KLi/0.95/04.06 ABSOLUTE MAXIMUM RATINGS (Note 1) SYMBOL PARAMETER Value UNITS V5 5V Power Supply 6 V Vlogic Input Logic Level -0.3 to V5 +0.3 V TA Operating Free-air Temperature Range -40 to 85 °C TSTORE Storage Temperature Range -55 to 150 °C TJMAX Maximum Junction Temperature 150 °C ESDHB ESD Susceptibility – Human Body Model (Note 2) 2000 V ESDMM ESD Susceptibility – Machine Model (Note 3) 200 V Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. See the table below for Operating Conditions. Note 2: Human body model, 100pF discharged through a 1.5kΩ resistor. Note 3: Machine model, 220pF – 240pF discharged through all pins. OPERATING CONDITIONS (Note 4) SYMBOL PARAMETER MIN. TYP. MAX. UNITS V5 Supply Voltage 4.5 5 5.5 V TA Operating Temperature Range -40 25 85 °C Note 4: Recommended Operating Conditions indicate conditions for which the device is functional. See Electrical Characteristics for guaranteed specific performance limits. THERMAL CHARACTERISTICS SYMBOL PARAMETER Value UNITS θJA Junction-to-ambient Thermal Resistance (still air) 80 °C/W

Tripath Technology, Inc. - Technical Information 3 TCA2002 – KLi/0.95/04.06 ELECTRICAL CHARACTERISTICS (Note 5) TA = 25 °C. See Application/Test Circuit. SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNITS Iq Quiescent Current (Mute = 0V) V5 = 5V 45 60 mA IMUTE Mute Supply Current (Mute = 5V) V5 = 5V TBD TBD mA VIH High-level input voltage (MUTE) 3.5 V VIL Low-level input voltage (MUTE) 1.0 V VOH High-level output voltage (HMUTE) I OH = XmA TBD V VOL Low-level output voltage (HMUTE) I OL = XmA TBD V VOH High-level output voltage (Yx, YxB) I OH = XmA TBD V VOL Low-level output voltage (Yx, YxB) I OL = XmA TBD V VTOC Over Current Comparator Voltage Threshold (OCD1 and OCD2) 0.85 0.97 1.09 V IVPPSENSE VPPSENSE Threshold Currents Over-voltage turn on (muted) Over-voltage turn off (mute off) Under-voltage turn off (mute off) Under-voltage turn on (muted) 121.6 45.6 151.4 61.2 µA µA µA µA VVPPSENSE Threshold Voltages with RVPP1 = RVPP2 = 383KΩ (Note 6) Over-voltage turn on (muted) Over-voltage turn off (mute off) Under-voltage turn off (mute off) Under-voltage turn on (muted) 46.6 17.5 58.0 23.4 V V V V IVNNSENSE VNNSENSE Threshold Currents Over-voltage turn on (muted) Over-voltage turn off (mute off) Under-voltage turn off (mute off) Under-voltage turn on (muted) 118.7 41.0 153.4 58.3 µA µA µA µA VVNNSENSE Threshold Voltages with RVNN1 = 392KΩ RVNN2 = 1.2MΩ (Note 6) Over-voltage turn on (muted) Over-voltage turn off (mute off) Under-voltage turn off (mute off) Under-voltage turn on (muted) 46.5 16.1 60.1 22.9 V V V V Note 5: Minimum and maximum limits are guaranteed but may not be 100% tested. Note 6: These supply voltages are calculated using the I VPPSENSE and I VNNSENSE values shown in the Electrical Characteristics table. They are shown for example on ly and are based on a +/-45V typical supply voltage. The voltage values shown are calculated using R VPP and R VNN values without any tolerance variation. Tripath recommends 1% tolerance (or better) sense re sistors for all applications. Please refer to the Application Information section for a more detailed des cription of how to calculate the over and under voltage trip voltages for a given resistor value.

Tripath Technology, Inc. - Technical Information 4 TCA2002 – KLi/0.95/04.06 TCA2002 PIN DESCRIPTION Pin Function Description BIASCAP Bandgap reference times two (typically 2.5VDC). Used to set the common mode voltage for the input op amps. This pin is not capable of driving external circuitry. FBKP2 FBKP1 Positive switching feedback (Channels 2 & 1)

3 DCMP

Internal mode selection. Grounding this pin enables 16-pulses during startup. Connecting this pin to V5 disables 16-pulses during startup, which minimizes turn-on pop. DCMP must be grounded when connected to fet drivers or power stages using bootstrapped high-side supplies. FBKN2 FBKN1 Negative switching feedback (Channels 2 & 1) 5 VPWR Test pin. Must be left floating. 8 HMUTE Logic output. A logic high indicates both amplifiers are muted, due to the mute pin state, or a “fault”. 9, 12 Y1, Y2 Non-inverted switching modulator outputs. (Channels 1 & 2) 10, 11 Y1B, Y2B Inverted switching mo dulator outputs. (Channels 1 & 2)

13 NC No connect

14,16 OCD2, OCD1 Over Current Detect inputs. If either pin exceeds VTOC, both amplifiers are muted. Ground if not used. The TCA2002 will try to automatically recover from an over current fault with an approximately 950mS repetition rate. 15 REF Internal reference voltage; approximately 1.0 VDC. Connect and 8.25kΩ, 1% to AGND. 17 VNNSENSE Negative supply voltage sense input. This pin is used for both over and under voltage sensing for the VNN supply. 18 OVRLDB A logic low output indicates the in put signal has overloaded the amplifier. 19 VPPSENSE Positive supply voltage sense input. This pin is used for both over and under voltage sensing for the VPP supply.

20 AGND Ground

21 V5 5 Volt power supply input. OAOUT1 OAOUT2 Input stage output pins. (Channels 1 and 2) 23, 28 INV1, INV2 Single-ended inputs. Inputs are a “virtual” ground of an inverting opamp with approximately 2.5VDC bias. The bias at INV1 and INV2 is active, even if the MUTE pin is high.

24 MUTE

When set to logic high, both amplifiers are muted and in idle mode. When low (grounded), both amplifiers are fully operational. If left floating, the device stays in the mute mode. Ground if not used. 25, 26 BBM1, BBM0 Break-before-make timing control to prevent shoot-through in the output MOSFETs. Please refer to the Application Information section additional information.

Tripath Technology, Inc. - Technical Information 5 TCA2002 – KLi/0.95/04.06 TCA2002 PINOUT BIASCAP FBKP2 DCMP FBKN2 VPWR FBKP1 FBKN1 HMUTE Y1B Y2B NC OCD2 14 15 REF OCD1 VNNSENSE OVRLDB VPPSENSE AGND OAOUT1 INV1 MUTE BBM1 BBM0 OAOUT2 INV2

Tripath Technology, Inc. - Technical Information 6 TCA2002 – KLi/0.95/04.06 APPLICATION / TEST DIAGRAM TCA2002 Typical Application Circuit *RFBC *RFBB RI CA 0.1uF OUT1 TCA2002 CFB CI *RFBC RF CI OUT2 *RFBB RI *RFBC RREF 8.25kΩ, 1% PGND1 1 2 *RFBB PGND2 Y1B HMUTE Y2B REF OCD1 VNNSENSE AGND MUTE BBM1 BBM0 OAOUT2 INV2 BIASCAP FBKGND2 DCMP FBKOUT2 VPWR FBKGND1 FBKOUT1 HMUTE Y1B Y2B NC OCD2 *RVNN1 ROFB IN1 COF 0.1uF ROFA IN2 ROFB COF 0.1uF RF OAOUT1 INV1 ROFB ROFA

19 VPPSENSE

0.1uF RFBA RFBA *RFBB CFB RFBA RFBA *RVNN2 *RVPP1 *RVPP2 20kΩ 20kΩ 20kΩ 10kΩ 2.2uF 510kΩ 510kΩ 10kΩ 510kΩ ROFB 510kΩ 20kΩ 20kΩ 2.2uF 20kΩ 1KΩ 1.1KΩ 1KΩ 1.1KΩ 1KΩ 10KΩ 10KΩ 10KΩ 10KΩ 1.1KΩ 1KΩ 1.1KΩ *RFBC * Component values must be adjusted based on amplifier supply voltage

Tripath Technology, Inc. - Technical Information 7 TCA2002 – KLi/0.95/04.06 EXTERNAL COMPONENTS DESCRIPTION (Refer to the Application/Test Circuits) Component Description RI Inverting input resistance to provide AC gain in conjunction with R F. This input is biased at the BIASCAP voltage (approximately 2.5VDC). RF Feedback resistor to set AC gain in conjunction with R I. Please refer to the Amplifier Gain paragraph, in the Application Information section. CA BIASCAP decoupling capacitor. Should be located close to pin 1 and grounded at pin 20. CI AC input coupling capacitor, which, in conjunction with R I, forms a high pass filter at )CR2(1f IIC π= . RFBA Feedback resistor divider connected to 5V. This resistor is normally set to 1kΩ. RFBB Feedback divider resistor connected to AGND. The value of this resistor depends on the supply voltage setting and helps set gain in conjunction with RI, RF, RFBA ,RFBB, and RFBC. RFBC Feedback resistor connected from either the OUT1A/OUT2A to FBKOUT1/FBKOUT2 or OUT1B/OUT2B to FBKGND1/FBKGND2. The value of this resistor depends on the supply voltage setting and helps set gain in conjunction with R I, RF, RFBBA, RFBB, and RFBC. It should be noted that the resistor from OUT1/OUT2 to FBKOUT1/FBKOUT2 must have a power rating of greater than )(2RVPPP FBC2 DISS = . CFB Feedback delay capacitor that both lowers the idle switching frequency and filters very high frequency noise from the feedback signal, which improves amplifier performance. The value of CFB should be offset between channel 1 and channel 2 so that the idle switching difference is greater than 40kHz. ROFA Potentiometer used to manually trim the DC offset on the speaker output. ROFB Resistors that limit the manual DC offset trim range and allows for more precise adjustment. COF Supply decoupling for the offset trim circuit. RREF Bias resistor. Locate close to pin 15 and ground at pin 20. CS Supply decoupling for the power supply pins. For optimum performance, these components should be located close to the TCA2002 and returned to their respective ground as shown in the Application/Test Circuit. RVNN1 Main over-voltage and under-voltage sens e resistor for the negative supply (VNN). RVNN2 Secondary over-voltage and under-voltage sense resistor for the negative supply (VNN). This resistor accounts for the internal VNNSENSE bias of 1.25V. Nominal resistor value should be three times that of RVNN1. RVPP1 Main over-voltage and under-v oltage sense resistor for the positive supply (VPP). RVPP2 Secondary over-voltage and under-voltage se nse resistor for the positive supply (VNN). This resistor accounts for the internal VPPSENSE bias of 2.5V. Nominal resistor value should be equal to that of RVPP1.

Tripath Technology, Inc. - Technical Information 9 TCA2002 – KLi/0.95/04.06 Amplifier Gain The gain of an amplifier based on the TCA2002 is the product of the input stage gain and the modulator gain. Please refer to the sections, Input Stage Design, and Modulator Feedback Design, for a complete explanation of how to determine the external component values for the various amplifier configurations. MODULATORV EVINPUTSTAG VTK2150 A* AA = For example, using a TCA2002 with the following external components, in a Single Ended, Split Supply Application R I = 20kΩ RF = 30.1kΩ RFBA = 1kΩ R FBB = 1.1kΩ R FBC = 10.0kΩ V V13.35- 11.1k Ω*1.0k Ω )1.1k(1.0k Ω*10.0k Ω 30.1k Ω 20k ΩAVTCA2002 =  +Ω+−≈ Input Stage Design The TCA2002 input stage is configured as an inve rting amplifier, allowing the system designer flexibility in setting the input stage gain and frequency response. Figure 2 shows a typical application where the input stage is a constant gain invertin g amplifier. The input stage gain should be set so that the maximum input signal level will drive the input stage output to 4Vpp. TCA2002 INPUT2 OAOUT2 OAOUT1 CI INV1INPUT1 BIASCAP AGND RF RICI RF AGND INV2 RI Figure 2: Input Stage The gain of the input stage, above the low frequency high pass filter point, is that of a simple inverting amplifier: It should be noted that the input amplif iers are biased at approximately 2.5VDC. Thus, the polarity of CI must be followed as shown in Figure 2 for a standard ground referenced input signal I F STAGE INPUTV R RA −=

Tripath Technology, Inc. - Technical Information 12 TCA2002 – KLi/0.95/04.06 It should be noted that only one channel of the modulator is required to create a bridged amplifier. This is done by reversing the Y1 and Y1B connecti ons to the second FET driver. This creates an out of phase signal at HB OUTN with respect to HB OUTP. A bridged amplifier has the advantage of potentially 4 ti mes the output power for a given supply rail. But the disadvantage is that the required numbe r of FET drivers and MOSFETs per channel increases by a factor of two. The modulator feedback resistors are: Ω= 1Ktypically specified, UserRFBA 2)-(VPP VPP*RR FBA FBB = VPP*RR FBA FBC = 1R*R )R(R*RA FBBFBA FBBFBAFBC MODULATOR-V ++≈ The above equations assume that VPP=|VNN|. For example, in a system with a SPLIT-SUPPLY, BRIDGED OUTPUT amplifier of VPP MAX=60V and VNNMAX=-60V, R FBA = 1kΩ, 1% R FBB = 1.071kΩ, use 1.07kΩ, 1% R FBC = 15.0kΩ, use 15.0kΩ, 1% The resultant modulator gain is: 30.02V/V 11.07k Ω*1.0k Ω )1.07k(1.0k Ω*15.0k Ω MODULATOR-AV =+Ω+≈ For SINGLE-SUPPLY, BRIDGED OUTPUT operation: Figure 5: Single Supply, Bridged Output (One Channel) FET DriverTCA2002 MOSFETS Y1B HIN1 LIN1 VPP FBKN1FBKP1 HB OUTP RFBB RFBA RFBC RFBB RFBA RFBC HS OUT1 LS OUT1 HS GATE1 LS GATE1 HS OUT2 LS OUT2 HS GATE2 LS GATE2 HB OUTN HIN2 LIN2

Tripath Technology, Inc. - Technical Information 13 TCA2002 – KLi/0.95/04.06 Figure 5 shows the basic single supply, bridged ou tput amplifier using a TCA2002. The MOSFET output stage operates from a single power supply, VPP (for instance 60VDC). Both terminals of the speaker are actively driven. Differential feedback is taken from each half-bridge output. The resistor divider networks at the TCA2002 scale the feedback signals. The resistor values are determined based on the supply voltage, as explained below. It should be noted that only one channel of the modulator is required to create a bridged amplifier. This is done by reversing the Y1 and Y1B connecti ons to the second FET driver. This creates an out of phase signal at HB OUTN with respect to HB OUTP. A bridged amplifier has the advantage of potentially 4 ti mes the output power for a given supply rail. But the disadvantage is that the required numbe r of FET drivers and MOSFETs per channel increases by a factor of two. The modulator feedback resistors are: Ω= 1K typicallyspecified,User R FBB 1000*350R FBC −= VPP )R(1000 R* 2333.33R FBC FBC FBB 1R*R )R(R*RA FBBFBA FBBFBAFBC MODULATOR-V ++≈ For example, in a system with a SINGLE-SUPPLY, BRIDGED OUTPUT amplifier of VPPMAX = 60V, R FBA = 2.22kΩ, use 2.21kΩ, 1% R FBB = 1kΩ, 1% R FBC = 20kΩ, 1% The resultant modulator gain is: 30.05V/V 12.21k Ω*1.0k Ω )2.21k(1.0k Ω*20.0k ΩA MODULATOR-V =+Ω+≈ Mute Control When a logic high signal is supplied to MUTE, both amplifier channels are muted (both high- and low- side transistors are turned off). When a logic level low is supplied to MUTE, both amplifiers are fully operational. Please note, that unlike previous Tripath controllers such as TC2000 and TC2001, the state of MUTE does not effect the input stage biasing. Thus, even if MUTE is high, the bias at INV1 will be active. This will keep the input capacitor, CI, charged via RI, thus, minimizing turn-on pops. Please note that the TCA2002 requires about 250mS to become active, after the de-assertion of MUTE (MUTE logic high Æ MUTE logic low). Also, the TCA2002 requires about 350uS to go into mute, after the assertion of MUTE (MUTE logic low Æ logic high). Break-Before-Make (BBM) Timing Control The TCA2002 can also insert a delay between the Yx and YxB output signals. This dead time will minimize shoot thru currents, in the case that th e output driver or power stage does not have built in BBM circuitry. BBM0 and BBM1 are logic inputs (connected to logic high or pulled down to logic low) that control the break-before-make timing of the output transistors according to the following table.

Tripath Technology, Inc. - Technical Information 14 TCA2002 – KLi/0.95/04.06 BBM1 BBM0 Delay 0 0 120 ns 0 1 80 ns 1 0 40 ns 1 1 0 ns Table 1: BBM Delay The tradeoff involved in making this setting is that as the delay is reduced, distortion levels improve but shoot-through and power dissipation increase. The actual amount of BBM required is dependent upon components such as MOSFET type and gate resistor value as well as circuit board layout. The BBM value selected should be verified in the actual application circuit board. It should also be verified under maximum temperature and power conditions since shoot-through in the output MOSFETs can increase under these conditions, possibly requiring a higher BBM setting than at room temperature. The voltage at the BBM pins is sampled at the falling edge of mute. Thus, the BBM cannot be dynamically adjusted based on the output level of the amplifier. Output Voltage Offset The TCA2002 does not have internal compensation for DC offset. The circuit shown in the Typical Application circuit is a simple passive circuit that covers the range of expected offset voltage. Tripath has had success with both active and passive circuits for this purpose; please consult with the Tripath Applications team for further information. HMUTE The HMUTE pin is a 5V logic output that indicates various fault conditions within the device. Also, HMUTE will be high if the MUTE input is connected to a logic high level. OVRLDB The OVRLDB pin is a 5V logic output that is asse rted just at the onset of clipping. When low, it indicates that the level of the input signal has overloaded the amplifier resulting in increased distortion at the output. The OVRLDB signal can be used to cont rol a distortion indicator light or LED through a simple buffer circuit, as the OVRLDB cannot drive an LED directly. There is a 20K resistor on chip in series with the OVRLDB output. If only 1 channel of the TCA2002 is used, the OVERLDB pin will be permanently low, since one modulator will not be switching. This can be alleviated if the unused (not connected to a power stage) modulator is run in self-feedback mode, via a few ex ternal resistors. Please contact your local sales office for more information. Over-current Protection The TCA2002 has two over-current protection co mparator inputs, located at OCD1 and OCD2. These inputs can be connected to an external power stage, over current circuit output, such as that of TP2150B or similar. When the voltage across R OCR becomes greater than VTOC (approximately 0.97V) the TCA2002 will mute. Please note that the voltage at a given OCDx pin will need to exceed VTOC for 3uS for the fault to register. The low pass filter formed by ROCR and COCR further enhances this time-based deglitching. Upon an over-current fault, the HMUTE signal will be pulled high and both Yx and YxB will be low. Please note that both channels are muted if an over-current condition occurs. The reaction to an over-current fault is different than previous Tripath controllers. Unlike previous controllers that latched an over-current fault, the TCA2002 will automatically try to recover. Once an

Tripath Technology, Inc. - Technical Information 15 TCA2002 – KLi/0.95/04.06 over current fault has occurred, the HMUTE will be pulled high for approximately 700mS. At this point, HMUTE will go low, and the TCA2002 will begin its normal un-muting sequence for 250mS. Thus, the typical retry time from an over-current fault is 950mS If over-current detection is not needed, for example in the cases where the power stage has built in over-current protection, simply connect OCD0 and OCD1 to AGND. This will disable the over-current detection comparators in the TCA2002. Over- and Under-Voltage Protection The TCA2002 senses the power rails through external resistor networks connected to VNNSENSE and VPPSENSE. The over- and under-volt age limits are determined by the values of the resistors in the networks (see APPLICATION / TEST DIAGRAM) . If the supply voltage falls outside the upper and lower limits determined by the resistor networks, the TCA2002 will mute. The HMUTE pin will be pulled high and the Yx and YxB pins will be low. The removal of the over-voltage, or under-voltage condition, returns the amplifier to normal operation . Please note that trip points specified in the Electrical Characteristics table are at 25°C and may change over temperature. For applications where the TCA2002 is mated wi th a power stage that has built-in over and undervoltage protection, this protection feature can be disabled by connecting a 30kohm resistor from VPPSENSE (pin 19) to V5, and a 15k resistor from VNNSENSE (pin 17) to AG ND. Please note that the MUTE pin must be held high until all power su pplies are stable to eliminate any possible power supply sequencing problems. The TCA2002 has built-in over and under voltage pr otection for both the VPP and VNN supply rails. The nominal operating voltage will typically be chosen as the supply “center point.” This allows the supply voltage to fluctuate, both above and below, the nominal supply voltage. VPPSENSE (pin 19) performs the ov er and undervoltage sensing fo r the positive supply, VPP. VNNSENSE (pin 17) performs the same function for the negative rail, VNN. When the current through R VPPSENSE (or R VNNSENSE) goes below or above the values shown in the ELECTRICAL CHARACTERISTICS section (caused by changing the power su pply voltage), the amplifier will be muted. VPPSENSE is internally biased at 2.5V and VNNSENSE is biased at 1.25V. Once the supply comes back into the supply voltage operating range (as defined by the supply sense resistors), the amplifier will automatically be un-muted and will begin to amplify. There is a hysteresis range on both the VPPSENSE and VNNSENSE pins. If the amplifier is powered up in the hysteresis band the amplifier will be muted. Thus, the usable supply range is the difference between the over- voltage turn-off and under-voltage turn-off for both the VPP and VNN supplies. It should be noted that there is a timer of approximately 200mS with respect to the over and under voltage sensing circuit. Thus, the supply voltage must be outside of the user defined supply range for greater than 200mS for the amplifier to be muted. Figure 6 shows the proper connection for the Ov er / Under voltage sense circuit for both the VPPSENSE and VNNSENSE pins.

Tripath Technology, Inc. - Technical Information 16 TCA2002 – KLi/0.95/04.06 RVPP2 VNN RVNN1 RVPP1 RVNN2 VPPSENSE VNNSENSE VPPV5 TCA2002 Figure 6: Over / Under voltage sense circuit The equation for calculating R VPP1 is as follows: VPPSENSE VPP1 I VPPR = Set VPP1 VPP2 RR = . The equation for calculating R VNNSENSE is as follows: VNNSENSE VNN1 I VNNR = Set VNN1 VNN2 R3R ×= . IVPPSENSE or IVNNSENSE can be any of the currents shown in the Electrical Characteristics table for VPPSENSE and VNNSENSE, respectively. The two resistors, R VPP2 and R VNN2 compensate for the internal bias points. Thus, R VPP1 and R VNN1 can be used for the direct calculation of the actual VPP and VNN trip voltages without considering the effect of RVPP2 and RVNN2. Using the resistor values from above, the actual minimum over voltage turn off points will be: RN_OFF)(MIN_OV_TU VPPSENSEVPP1 N_OFFMIN_OV_TUR IRVPP ×= )IR(VNN RN_OFF)(MIN_OV_TU VNNSENSEVNN1 N_OFFMIN_OV_TUR ×−= The other three trip points can be calculated using the same formula but inserting the appropriate IVPPSENSE (or I VNNSENSE) current value. As stated earlier, t he usable supply range is the difference between the minimum overvoltage turn off and maximu m under voltage turn-off for both the VPP and VNN supplies. N_OFFMAX_UV_TURN_OFFMIN_OV_TUR RANGE VPP-VPPVPP = N_OFFMAX_UV_TURN_OFFMIN_OV_TUR RANGE VNN-VNNVNN =

Tripath Technology, Inc. - Technical Information 17 TCA2002 – KLi/0.95/04.06

Tripath Technology, Inc. - Technical Information 18 TCA2002 – KLi/0.95/04.06 PRELIMINARY INFORMATION – The above specification is for a device that is currently in development. All specifications and device descriptions are subject to change based on product analysis and characterization. Please contact Tripath Technology for additional information not included or covered in this advanced document. Tripath Technology Inc. reserves the right to make changes without further notice to any products herein to improve reliability, function or design. Tripath does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights, nor the rights of others. Tripath and Digital Power Processing are trademarks of Tripath Technology Inc. Other trademarks referenced in this document are owned by their respective companies. TRIPATH’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN CONSENT OF THE PRESIDENT OF TRIPATH TECHNOLOGY INC. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in this labeling, can be reasonably expected to result in significant injury to the user. 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. For more information on Tripath products, visit our web site at: www.tripath.com Contact Information TRIPATH TECHNOLOGY, INC

2560 Orchard Parkway, San Jose, CA 95131

408.750.3000 - P 408.750.3001 - F For more Sales Information, please visit us @ www.tripath.com/cont_s.htm For more Technical Information, please visit us @ www.tripath.com/data.htm