View EL7556BC_113399.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
Features
* EL7556C/EL7556AC Pincompatible * Improved temperature and voltage ranges * 6A continuous load current * Precision internal 1% reference * 1.0V to 3.8V output voltage * Internal power MOSFETs * >90% efficiency * Synchronous switching * Adjustable slope compensation * Over-temperature indicator * Pulse-by-pulse current limiting * Operates up to 1MHz * 1.5% typical output accuracy * Adjustable oscillator with sync * Remote enable/disable * Intel P54- and P55-compatible * VCC2DET interface * Internal soft-start
General Description
The EL7556BC is an adjustable synchronous DC:DC switching regulator optimized for a 5V input and 1.0V-3.8V output. By combining integrated NMOS power FETS with a fused-lead package, the EL7556BC can supply up to 6A continuous output current without the use of external power devices or discrete heat sinks, thereby minimizing design effort and overall system cost. On-chip resistorless current sensing is used to achieve stable, highly efficient, current-mode control. The EL7556BC also incorporates the VCC2DET function to directly interface with the Intel P54 and P55 microprocessors. Depending on the state of VCC2DET, the output voltage is internally preset to 3.5V or a user-adjustable voltage using two external resistors. In both internal and external feedback modes the active-high PWRGD output indicates when the regulator output is within 10% of the programmed voltage. An on-board sensor monitors die temperature (OT) for over-temperature conditions and can be connected directly to OUTEN to provide automatic thermal shutdown. Adjustable oscillator frequency and slope compensation allow added flexibility in overall system design. The EL7556BC is available in a 28-pin SO package and is specified for operation over the full -40C to +85C temperature range.
Applications
* * * * * * PC motherboards Local high power CPU supplies 5V to 1.0V DC:DC conversion Portable electronics/instruments P54 and P55 regulators GTL+ Bus power supply
Connection Diagram
R4 R3 100 150
VIN
D3
1 C4 0.1F 2 C7 39pF 3 C8 R5 5 5.1 6 220pF 4
FB1 CREF CSLOPE COSC VDD VIN VSSP VIN VSSP
FB2 28 CP C2V VSS 27 R1 26 20 25 R6 VHI 24 C6 LX LX LX LX VSSP VSSP TEST 23 0.1F 22 21 20 19 18 17 L1 2.5H C10 1mF 39.2 D1 C11 0.22F C5 1F D2 D4* (Optional)
Ordering Information
Part No EL7556BCM EL7556BCM-T13 Package 28-Pin SO 28-Pin SO Tape & Reel 13" Outline # MDP0027 MDP0027
7 C9 C12 1F C3 1F 8 9
VOUT = 1V*(1+R3/R4)
VIN
660F
10 VSSP 11 VSSP 12 VSSP Connect to VSSP for external feedback 13
October 5, 2001
VCC2DET 16 PWRGD OT 15
14 OUTEN
EL7556BC
C12 - 1F C3, C4, C5, C6, C7 C8 - ceramic C5, C11 - ceramic or tantalum C9 - Sprague 293D337X96R3 2X330F C10 - Sprague 293D337X96R3 3X330F L1 - Pulse Engineering, PE-53681 D1-D4: BAT54S fast diode D4 Required for EL7556ACM Only
Manufactured under U.S. Patents No. 5,723,974 and No. 5,793,126
Note: All information contained in this data sheet has been carefully checked and is believed to be accurate as of the date of publication; however, this data sheet cannot be a "controlled document". Current revisions, if any, to these specifications are maintained at the factory and are available upon your request. We recommend checking the revision level before finalization of your design documentation.
(c) 2001 Elantec Semiconductor, Inc.
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
Absolute Maximum Ratings (T
Storage Temperature Range Supply (VIN) Ambient Operating Temperature
A
= 25C)
-65C to +150C 6.0V -40C to +85C
Output Pins Operating Junction Temperature Peak Output Current
-0.3V below GND, +0.3V above VDD 135C 9A
Important Note: All parameters having Min/Max specifications are guaranteed. Typ values are for information purposes only. Unless otherwise noted, all tests are at the specified temperature and are pulsed tests, therefore: TJ = TC = TA.
Electrical Characteristics
VDD = VIN = 5V, COSC = 1nF, CSLOPE = 470pF, TA = 25C unless otherwise specified. Parameter General IDD IDDOFF IVIN VOUT1 VOUT2 VOUTLINE VOUTLOAD RSHORT II MAX VOUTTC TOT THYS VPWRGD VDDOFF VDDON VHYS MSS DMAX IPUP ICSLOPE IFB1 ROT VIH VIL VOH PWGD VOL PWGD VREF VREFTC VREFLOAD VDD Supply Current VDD Standby Current VIN No Load Current Output Initial Accuracy Output Initial Accuracy Output line Regulation Output Load Regulation Short Circuit Load Resistance Current Limit Output Tempco Over Temperature Threshold Over Temperature Hysteresis Power Good Threshold Relative to Programmed Output Voltage Minimum VDD for Shutdown Maximum VDD for Startup Input Hysteresis Soft start slope Maximum duty cycle VCC2DET, OUTEN Pull Up Current Cslope Charging Current FB1 Input Pull Up Current Over Temperature Pull Up Resistance VCC2DET, OUTEN Input High VCC2DET, OUTEN Input Low Powergood Drive High Powergood Drive Low Reference Accuracy Reference Voltage Tempco Reference Load Regulation 0Controller - Inputs
Controller - Reference
2
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
Electrical Characteristics
VDD = VIN = 5V, COSC = 1nF, CSLOPE = 470pF, TA = 25C unless otherwise specified. Parameter Controller - Doubler VC2V FRAMP IOSC CHG IOSC DIS FOSC tSYNC Power - FET ILEAK RDSON RDSONTC tBRM tLEB LX Output Leakage to VSS Composite FET Resistance RDSON Tempco FET break before make delay High side FET minimum on time (LEB) LX = 0V 18 0.1 10 140 100 30 A m m/C ns ns Voltage Doubler Output Oscillator Ramp Amplitude Oscillator Charge Current Oscillator Discharge Current Oscillator initial accuracy Minimum oscillator sync width 0.2V3
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
Typical Performance Curves
Efficiency vs I LOAD (VOUT =3.5V) VDD=VIN=5.0V (10%) VDD=4.5V Efficiency vs I LOAD (VDD=5.0V) 100 95 90 85 80 75 TA=25C 1.5 2.5 3.5 IOUT (A) Line Regulation (C SLOPE=100pF) 3.54 3.53 3.52 3.51 VOUT (V) 3.50 3.49 3.48 3.47 3.46 4.5 IOUT=6A 5.0 VIN (V) Line Regulation vs CSLOPE (IOUT=3A) VDD=VIN=5.0V 10% TA=25C TA=25C 5.5 IOUT=3A IOUT=0.5A VOUT (V) 3.54 3.53 3.52 3.51 3.50 3.49 3.48 3.47 3.46 0.5 TA=25C 3.0 IOUT (A) VIN=4.5V 6.0 VIN=5V VIN=5.5V 4.5 5.5 6.5 70 0.5 1.5 2.5 3.5 IOUT(A) 4.5 5.5 6.0 VCC=3.5V VCC=2.5V
96 94 92 Efficiency (%)
88 86 84 82 80 0.5 VDD=5.5V
Efficiency (%)
90
VDD=5V
VCC=1V
Load Regulation (C SLOPE=100pF)
0.8 0.7 0.6 VOUT () (%)
0.6 0.5
Load Regulation vs CSLOPE (VIN=5.0V) IOUT=3A, +3A, -2.5A TA=25C VOUT=3.5A
0.4 0.3 0.2 0.1 0.0 50 75
VOUT=3.5A VOUT=2.5A
VOUT () (%)
0.5
0.4 0.3 0.2 0.1 VOUT=1A
VOUT=2.5A
VOUT=1A 100 125 150 175 0.0 50 75 100 125 150 175
CSLOPE (pF)
CSLOPE (pF)
4
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
Typical Performance Curves
Line Regulation vs CSLOPE VIN=VDD=5.0V 10% TA=25C Load Regulation vs CSLOPE IOUT=3A, +3A, -2.5A TA=25C
0.8 0.7 0.6 VOUT () (%)
0.8 0.7 0.6 VOUT () (%) 0.5 0.4 0.3 0.2 0.1
0.5 0.4 0.3 0.2 0.1 0.0 50 75 100 125 150 175 IOUT=0.5A IOUT=6A
VIN=4.5V
VIN=5V
VIN=5.5V
0.0 50
75
100
125
150
175
CSLOPE (pF) VOUT vs CSLOPE (VIN=5.0V, ILOAD=0.5A)
CSLOPE (pF) VOUT Variation vs Programmed Output Voltage [VIDEAL=(1+R3/R4)] TA=25C 1.0
CS CO
1.5 1.0 0.5 VOUT () (%) 0.0 -0.5 -1.0 -1.5 -2.0 -2.5
1.5
VOUT=1V
Deviation in VOUT (%)
VOUT=2.5V VOUT=3.5V
0.5 0.0 -0.5 -1.0
SC =
LO PE = 1
22
00
0p
pF
F
TA=25C 75 100 125 150 175
Loop Gain Induced Error -1.5 1.0 1.5 2.0 2.5 VIDEAL (V) FOSC vs Temperature 520 3.0 3.5 4.0
-3.0 50
CSLOPE (pF) FOSC vs C OSC 1000 TA=25C 1000 FOSC (kHz) FOSC (kHz)
510 500 490 480 470 460 VDD=5V
VDD=4.5V
100
VDD=5.5V
10
1 10
100 COSC (pF)
1k
100k
450
0
20
40
60
80
100
120
140
Temperature (C)
5
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
Typical Performance Curves
I(VDD) + I(VIN) vs FOSC 60 50 40 IVIN (mA) IQ (mA) 30 20 10 Discontinuous Mode 0 200 400 600 FOSC (kHz) I(V DD) vs FOSC 50 45 40 35 IDD (mA) 30 25 20 15 10 5 0 200 400 600 FOSC (kHz) Power On Reset 40 TA=25C OUTEN=VDD 30 IQ (mA)) FOSC=500k VOUT (V) 2.3 2.1 1.9 1.7 1.5 1.3 1.1 0.9 0 2.5 3.0 3.5 VDD(V) 4.0 4.5 5.0 0.7 FOSC (kHz) VDD=4.5V VDD=5V TJ=120C VDD=5.5V 800 1000 1.0 10 100 FOSC (kHz) Minimum Output Voltage vs FOSC 100 VDD=4.5V VDD=5V TA=25C OUTEN=VDD VDD=5.5V IDD (mA) + IVIN VDD=5.5V 1.5 VDD=4.5V 2.0 IDD + IVIN vs FOSC Continuous Mode 800 1000 VDD=4.5V VDD=5V TA=25C OUTEN=VDD VDD=5.5V 16 14 12 10 8 6 4 2 Discontinuous Mode 0 200 400 VDD=4.5V Continuous Mode 600 FOSC (kHz) 800 1000 VDD=5V TA=25C OUTEN=VDD VDD=5.5V I(VIN) vs FOSC
VDD=5V
20
10
6
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
Typical Performance Curves
JA vs Cu Area 41 39 37 JA (C/W) ILOAD (A) 35 33 31 29 27 25 0.00 1.00 2.00 3.00 Board with Inductor Board with no Components 8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 5.00 6.00 4.0 25 OUTEN connected to OT 30 35 40 45 50 55 60 65 70 Still Air 100 LFPM Maximum ILOAD vs Temperature 7556 Demo Board (31C/W)
4.00
Bare Cu Area (in2) RDSON vs Temperature 38 36 34 RDSON (m ) 32 30 28 26 24 22 20 0 25 50 75 100 125
TA (C)
Temperature (C)
7
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
Pin Descriptions
I = Input, O = Output, S = Supply Pin Number 1 Pin Name FB1 Pin Type I Function Voltage feedback pin for the buck regulator. Active when VCC2DET is logic low. Normally connected to external resistor divider between VOUT and GND. A 2A pull-up current forces VOUT to VSS in the event that FB1is floating and VCC2DET is inadvertently connected to GND. Bandgap reference bypass capacitor. Typically 0.1F to VSS. Slope compensation capacitor. Ramp width corresponds to LX duty cycle. CSLOPE to COSC ratio is normally 1:1.5. Oscillator timing capacitor. FOSC(Hz) can be approximated by: FOSC(Hz) = 0.0001/COSC. COSC in Farads. Power Supply for PWM control circuitry. Normally the same potential as VIN. Power supply for the buck regulator. Connected to the drain of the high-side NMOS FET. Ground return for the buck regulator. Connected to the source of the low-side synchronous NMOS FET. Same as pin 6. Same as pin 7. Same as pin 7. Same as pin 7. Same as pin 7. VCC2DET interface logic input. When driven to logic 1 VOUT = 3.500V. When driven to logic 0 the PWM uses FB1 to determine VOUT: VOUT = 1.0V*(1+R3/R4). The switching regulator output is enabled when logic 1. The reference voltage output operates whenever the power supply is qualified (VDD>VPOR) regardless of the state of this pin. Over temperature indicator. Normally high. Pulls low when die temperature exceeds 135C, returns to the high state when die temperature has cooled to 100C. Power good window comparator output. Logic 1 when regulator output is within 10% of programmed voltage. Test pin. Must be connected to VSSP in normal operation. Same as pin 7. Same as pin 7. Inductor drive pin. High current switching output whose average voltage equals the regulator output voltage. Same as pin 20. Same as pin 20. Same as pin 20. Gate drive to high-side driver. Bootstrapped from LX with a 0.1F capacitor. Ground return for the control circuitry. Connected to voltage doubler output. Supplies gate drive to the low-side driver. Drives the negative side of charge pump capacitor at one-half the oscillator frequency FOSC. Voltage feedback pin. Active when VCC2DET is logic 1. Internally preset to VOUT = 3.5V.
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
CREF CSLOPE COSC VDD VIN VSSP VIN VSSP VSSP VSSP VSSP VCC2DET OUTEN OT PWRGD TEST VSSP VSSP LX LX LX LX VHI VSS C2V CP FB2
I I I S S S S S S S S I I O O I S S O O O O I S I O I
8
Block Diagram
FB1, Pin1 FB2, Pin 28 2-1 MUX V2X VHI, Pin 24 + Current LEB TDELAY + Current Limit Q R S Q LX, Pin 20-23 + PWM VDD RSS VDD R UVLO CSS FF S VSSP, Pin 9-12, 18-19 + VDD and VIN, Pin 5,6,8 C2V, Pin 26 +
+
PWRGD, Pin 16 CP, Pin 27
VCCDET, Pin 13
CSLOPE, Pin 3
CREF, Pin 27 1.26V
+ 4V
OUTEN, Pin 14
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
9
+ S R +
Zero Cross Detect
COSC, Pin 4 OT, Pin 15 Over Temp Sensor VSS, Pin 25
EL7556BC
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
Applications Information
Circuit Description General
The EL7556BC is a fixed frequency, current mode controlled DC:DC converter with integrated N-channel power MOSFETS and a high precision reference. The device incorporates all of the active circuitry required to implement a cost effective, user-programmable 6A synchronous buck converter suitable for use in CPU power supplies. By combining fused-lead packaging technology with an efficient synchronous switching architecture, high power outputs (21W) can be realized without the use of discrete external heat sinks. the relatively large LC time constants found in power supply applications generally results in low bandwidth and poor transient response. By directly monitoring changes in inductor current via a series sense resistor the controller's response time is not entirely limited by the output LC filter and can react more quickly to changes in line or load conditions. This feed-forward characteristic also simplifies AC loop compensation since it adds a zero to the overall loop response. Through proper selection of the current-feedback to voltage-feedback ratio, the overall loop response will approach a one pole system. The resulting system offers several advantages over traditional voltage control systems, including simpler loop compensation, pulse by pulse current limiting, rapid response to line variation and good load step response. The heart of the controller is a triple-input direct summing comparator which sums voltage feedback, current feedback and slope compensating ramp signals together. Slope compensation is required to prevent system instability which occurs in current-mode topologies operating at duty-cycles greater than 50% and is also used to define the open-loop gain of the overall system. The compensation ramp amplitude is user adjustable and is set using a single external capacitor (CSLOPE). Each comparator input is weighted and determines the load and line regulation characteristics of the system. Current feedback is measured by sensing the inductor current flowing through the high-side switch whenever it is conducting. At the beginning of each oscillator period the high-side NMOS switch is turned on and CSLOPE ramps positively from its reset state (VREF potential). The comparator inputs are gated off for a minimum period of time (LEB) after the high-side switch is turned on to allow the system to settle. The Leading Edge Blanking (LEB) period prevents the detection of erroneous voltages at the comparator inputs due to switching noise. When programming low regulator output voltages the LEB delay will limit the maximum operating frequency of the circuit since the LEB will result in a minimum duty-cycle regardless of the PWM error voltage. This relationship is shown in the performance curves. If the inductor current exceeds the maximum current limit (ILMAX), a secondary over-current com10
Theory of Operation
The EL7556BC is composed of 7 major blocks: 1. PWM Controller 2. Output Voltage Mode Select 3. NMOS Power FETS and Drive Circuitry 4. Bandgap Reference 5. Oscillator 6. Temperature Sensor 7. Power Good and Power On Reset
PWM Controller
The EL7556BC regulates output voltage through the use of current-mode controlled pulse width modulation. The three main elements in a PWM controller are the feedback loop and reference, a pulse width modulator whose duty cycle is controlled by the feedback error signal, and a filter which averages the logic level modulator output. In a step-down (buck) converter, the feedback loop forces the time-averaged output of the modulator to equal the desired output voltage. Unlike pure voltagemode control systems current-mode control utilizes dual feedback loops to provide both output voltage and inductor current information to the controller. The voltage loop minimizes DC and transient errors in the output voltage by adjusting the PWM duty-cycle in response to changes in line or load conditions. Since the output voltage is equal to the time-average of the modulator output
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
parator will terminate the high-side switch. If ILMAX has not been reached, the regulator output voltage is then compared to the reference voltage VREF. The resultant error voltage is summed with the current feedback and slope compensation ramp. The high-side switch remains on until all three comparator inputs have summed to zero, at which time the high-side switch is turned off and the low-side switch is turned on. In order to eliminate cross-conduction of the high-side and low-side switches a 10ns break-before-make delay is incorporated in the switch driver circuitry. In the continuous mode of operation the low-side switch will remain on until the end of the oscillator period. In order to improve the low current efficiency of the EL7556BC, a zero-crossing comparator senses when the inductor transitions through zero. Turning off the low-side switch at zero inductor current prevents forward conduction through the internal clamping diodes (LX to VSSP) when the low-side switch turns off, reducing power dissipation. The output enable (OUTEN) input allows the regulator output to be disabled by an external logic control signal. drive for both the high-side and low-side switches is derived through a charge pump consisting of the CP pin and external components D1-D3 and C5-C6. The CP output is a low resistance inverter driven at one-half the oscillator frequency. This is used in conjunction with D2-D3 to generate a 7.5V (typical) voltage on the C2V pin which provides gate drive to the low-side NMOS switch and associated level shifter. In order to use an NMOS switch for the high-side drive it is necessary to drive the gate voltage above the source voltage (LX). This is accomplished by boot-strapping the VHI pin above the C2V voltage with capacitor C6 and diode D1. When the low-side switch is turned on the LX voltage is close to GND potential and capacitor C6 is charged through diodes D1-D3 to approximately 6.9V. At the beginning of the next cycle the high side switch turns on and the LX pin begins to rise from GND to VDD potential. As the LX pin rises the positive plate of capacitor C6 follows and eventually reaches a value of approximately 11.2V, for VDD=5V. This voltage is then level shifted and used to drive the gate of the high-side FET, via the VHI pin.
Output Voltage Mode Select
The VCC2DET multiplexes the FB1 and FB2 pins to the PWM controller. A logic 1 on VCC2DET selects the FB2 input and forces the output voltage to the internally programmed value of 3.50V. A logic zero on VCC2DET selects FB1 and allows the output to be programmed from 1.0 to 3.8V. In general:
R 3 V OUT = 1V x 1 + ----- x Volt R 4
Reference
A 1% temperature compensated band gap reference is integrated in the EL7556BC. The external CREF capacitor acts as the dominant pole of the amplifier and can be increased in size to maximize transient noise rejection. A value of 0.1uF is recommended.
Oscillator
The system clock is generated by an internal relaxation oscillator with a maximum duty-cycle of approximately 96%. Operating frequency can be adjusted through the COSC pin or can be driven by an external clock source. If the oscillator is driven by an external source, care must be taken in the selection of CSLOPE. Since the COSC and CSLOPE values determine the open loop gain of the system, changes to COSC require corresponding changes to CSLOPE in order to maintain a constant gain ratio. The recommended ratio of COSC to CSLOPE is 1.5:1
However, due to the relatively low open loop gain of the system, gain errors will occur as the output voltage and loop-gain are changed. This is shown in the performance curves. (The output voltage is factory trimmed to minimize error at a 2.50V output). A 2uA pull-up current from FB1 to VIN forces VOUT to GND in the event that FB1 is not used and the VCC2DET is inadvertently toggled between the internal and external feedback mode of operation.
NMOS Power FETS and Drive Circuitry
The EL7556BC integrates low resistance (25m) NMOS FETS to achieve high efficiency at 6A. Gate
11
Temperature Sensor
An internal temperature sensor continuously monitors die temperature. In the event that die temperature
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
exceeds the thermal trip-point, the OT pin will output a logic 0. The upper and lower trip points are set to 135 C and 100C respectively. To enable thermal shutdown this pin should be tied directly to OUTEN. Use of this feature is recommended during normal operation If the thermal shutdown pin is connected to OUTEN the IC will enter thermal shutdown when the maximum junction temperature is reached. For a thermal shutdown of 135C and power dissipation of 2.2W the ambient temperature is limited to a maximum value of 67C (typical). The ambient temperature range can be extended with the application of air flow. For example, the addition of 100LFM reduces the thermal resistance by approximately 15% and can extend the operating ambient to 77C (typical). Since the thermal performance of the IC is heavily dependent on the board layout, the system designer should exercise care during the design phase to ensure that the IC will operate under the worstcase environmental conditions.
Power Good and Power On Reset
During power up the output regulator will be disabled until VIN reaches a value of approximately 4.0V. Approximately 500mV of hysteresis is present to eliminate noise induced oscillations. Under-voltage and over-voltage conditions on the regulator output are detected through an internal window comparator. A logic 1 on the PWRGD output indicates that regulated output voltage is within 10% of the nominally programmed output voltage. Although small, the typical values of the PWRGD threshold will vary with changes to external feedback (and resultant loop gain) of the system. This dependence is shown in the typical performance curves.
Thermal Management
The EL7556BC utilizes "fused lead" packaging technology in conjunction with the system board layout to achieve a lower thermal resistance than typically found in standard 28-pin SO packages. By fusing (or connecting) multiple external leads to the die substrate within the package, a very conductive heat path to the outside of the package is created. This conductive heat path MUST then be connected to a heat sinking area on the PCB in order to dissipate heat out and away from the device. The conductive paths for the EL7556BC package are the fused leads: # 7, 9, 10, 11, 12, 18, and 19. If a sufficient amount of PCB metal area is connected to the fused package leads, a junction-to-ambient thermal resistance of approximately 31C/W can be achieved (compared to 78C/W for a standard SO28 package). The general relationship between PCB heat-sinking metal area and the thermal resistance for this package is shown in the Performance Curves section of this data sheet. It can be readily seen that the thermal resistance for this package approaches an asymptotic value of approximately 31C/W without any airflow. Additional information can be found in Application Note #8 (Measuring the Thermal Resistance of Power Surface-Mount Packages).
12
EL7556BC
EL7556BC
Integrated Adjustable 6 Amp Synchronous Switcher
General Disclaimer
Specifications contained in this data sheet are in effect as of the publication date shown. Elantec, Inc. reserves the right to make changes in the circuitry or specifications contained herein at any time without notice. Elantec, Inc. assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement.
WARNING - Life Support Policy
Elantec, Inc. products are not authorized for and should not be used within Life Support Systems without the specific written consent of Elantec, Inc. Life Support systems are equipment intended to support or sustain life and whose failure to perform when properly used in accordance with instructions provided can be reasonably expected to result in significant personal injury or death. Users contemplating application of Elantec, Inc. Products in Life Support Systems are requested to contact Elantec, Inc. factory headquarters to establish suitable terms & conditions for these applications. Elantec, Inc.'s warranty is limited to replacement of defective components and does not cover injury to persons or property or other consequential damages.
Printed in U.S.A.
October 5, 2001
Elantec Semiconductor, Inc.
675 Trade Zone Blvd. Milpitas, CA 95035 Telephone: (408) 945-1323 (888) ELANTEC Fax: (408) 945-9305 European Office: +44-118-977-6020 Japan Technical Center: +81-45-682-5820
13

▲Up To Search▲

Price & Availability of EL7556BC

	To Download EL7556BC Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .