View MAX5015EVKIT_313152.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

19-2053; Rev 2; 12/02
MAX5015 Evaluation Kit
General Description
The MAX5015 evaluation kit (EV kit) is a fully assembled and tested circuit board that contains a 50W forward converter in the industry-standard half-brick footprint. The circuit is configured for a +5.0V output voltage and provides up to 10A of current. Power for the circuit can be provided from either a +36V to +72V or -36V to -72V DC source. High efficiency of 86% is achieved at 5A using a single transistor, forward converter topology providing output power up to 50W. The surface-mount transformer provides galvanic isolation and has a reset winding to recover magnetic energy. Galvanic isolation up to 1500V is achieved by an optocoupler and surfacemount transformer. Operation at 280kHz allows the use of small magnetics and output capacitors. Warning: The MAX5015 EV kit is designed to operate with high voltages. Dangerous voltages are present on this EV kit and on equipment connected to it. Users who power up this EV kit or power the sources connected to it must be careful to follow safety procedures appropriate to working with high-voltage electrical equipment. Under severe fault or failure conditions, this EV kit may dissipate large amounts of power, which could result in the mechanical ejection of a component or of component debris at high velocity. Operate this kit with care to avoid possible personal injury. o +5V Output at 10A o VOUT Regulation better than 0.1% over Line and Load o 86% Efficiency at 48V Input and 5V/5A Output o Half-Brick Module Footprint and Pinout o Short-Circuit Protection o 275kHz Switching Frequency o Designed for 1500V Isolation o Soft-Start o Fully Assembled and Tested o Remote ON/OFF o Remote Sense
Features
o +36V to +72V or -36V to -72V Input Range
Evaluates: MAX5015
Ordering Information
PART MAX5015EVKIT TEMP RANGE 0C to +70C IC PACKAGE SO-8
Component List
DESIGNATION C1, C15 QTY 2 DESCRIPTION 0.1F 10%, 50V X7R ceramic capacitors (0805) Taiyo Yuden UMK212BJ104KG 0.01F 10%, 50V X7R ceramic capacitor (0805) Not installed (0805) 0.68F, 100V X7R ceramic capacitors (1812) TDK C4532X7R2A684K 560F, 6.3V electrolytic capacitors (8 x 11.5) Sanyo 6MV560WX 0.047F 10%, 50V X7R ceramic capacitor (0805) Taiyo Yuden UMK212BJ473KG 10F 20%, 16V X5R ceramic capacitor (1210) Taiyo Yuden EMK325BJ106MN
Component Suppliers
SUPPLIER Central Semiconductor Coiltronics Dale-Vishay General Semiconductor International Rectifier Murata Sanyo USA Taiyo Yuden TDK PHONE 516-435-1110 561-752-5000 402-564-3131 631-847-3000 310-322-3331 814-237-1431 619-661-6835 408-573-4150 847-803-6100 FAX 516-435-1824 561-742-0134 402-563-6418 631-847-3236 310-322-3332 814-238-0490 619-661-1055 408-573-4159 847-390-4405
C2 C3 C4, C5, C6
1 0 3
C7, C13, C14
3
C8
1
C9
1
Component List continued on next page.
Note: Please indicate that you are using the MAX5015 when contacting these component suppliers.
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim's website at www.maxim-ic.com.
MAX5015 Evaluation Kit Evaluates: MAX5015
Component List (continued)
DESIGNATION QTY DESCRIPTION 0.1F 10%, 16V X7R ceramic capacitor (0603) Taiyo Yuden EMK107BJ104KA 0.33F 10%, 35V X7R ceramic capacitor (0805) Taiyo Yuden GMK212BJ334KG 0.001F, 200V X7R ceramic capacitor (0603) Murata GRM39-X7R102K200 0.0047F, 250VAC X7R ceramic capacitor (2220) Murata GA355DR7GC472KY02L 0.022F 10%, 25V X7R ceramic capacitor (0603) Not installed 15V, 150mW zener diode (S-mini) Not installed 3V 150mW zener diode (S-mini) 80V, 100mA Schottky diode (S-mini) 40V, 20A Schottky diode (TO-220AB) General Semiconductor SBL2040CT 250V, 250mA high-voltage switching diode (SOD-123) Central Semiconductor CMHD2003 4.7H, 21.5A inductor Coiltronics, HC2-4R7 200V, 18A N-channel MOSFET (TO-220AB) International Rectifier IRF640N Not installed NPN transistor (SOT23) Not installed (0805) 20 5% resistor (1206) U3 1 DESIGNATION R5 R6 R7 R8 R9 R11 R12 R13 R15 R16, R17 T1 U1 U2 QTY 1 1 1 1 1 1 1 1 1 2 1 1 1 DESCRIPTION 240k 5% resistor (0805) 0.1 1% power resistor (1206) Dale Electronics, Inc. WSL-1206 0.1 1% 1 5% resistor (0805) 499 1% resistor (0805) 150 5% resistor (0805) 25.5k 1% resistor (0805) 8.25k 1% resistor (0805) 4.75k 1% resistor (0805) 3.32k 1% resistor (0805) 51 5% resistors (0805) 170H 1:0.857: 0.357:0.357 turn transformer (12-pin Gull Wing) Coiltronics CTX03-14856 MAX5015ESA (8 SO) 70V 100% to 200% CTR phototransistor (8-pin SO) QT Optoelectronics MOC207 1.24V precision shunt regulator (SOT23) Texas Instruments TLV431AIDBV Aluminum heatsink plate Vista Industrial Products 5015 Nylon spacers, 1/4 x 5/8 nylon Nylon screws, 4-40 x 1/4 Nylon screws, 4-40 x 1/2 Nylon screws, 6-32 x 3/8 TO-220AB Mica thermal insulating pads MAX5015 PC board MAX5015 data sheet MAX5015 EV kit data sheet
C10
1
C11
1
C12
1
C16
1
C17 D1 D2 D3
1 0 0 1
D4
1
None None None None None None None None None
1 2 2 2 2 2 1 1 1
D5
1
L1
1
N1
1
Q1 R1, R10 R3
0 0 1
2
_______________________________________________________________________________________
MAX5015 Evaluation Kit
Quick Start
The MAX5015 EV kit is fully assembled and tested. Follow these steps to verify board operation. Do not turn on the power supply until all connections are completed.
Shutdown
Shutdown Mode (Remote Control Method) The MAX5015 EV kit features a pin to remotely shutdown the forward converter. An open-collector/drain transistor or relay contact must be connected to the SHDN and VIN- pins of the EV kit. Table 1 lists the options.
Evaluates: MAX5015
Output
1) Connect a jumper wire from the VOUT pin to the +SENSE pin. 2) Connect a jumper wire from the SGND pin to the -SENSE pin. 3) Connect a voltmeter to the VOUT pin and SGND. 4) Connect a +36V to +72V power supply to the VIN+ pin. Do not exceed 100V input voltage. Connect the power supply's ground to the VIN- pin. 5) Turn on the power supply above +36V and verify that VOUT provides +5V at the voltmeter. For instructions on selecting the feedback resistors for other output voltages, refer to the Evaluating other Output Voltages section in this document.
Table 1. Shutdown Pin Function (Remote Control)
SHDN PIN Open Pull low MAX5015 OUTPUT MAX5015 Enabled, VOUT = +5.0V Shutdown mode, VOUT = 0V
Detailed Description
The MAX5015 EV kit is a 50W forward converter which provides +5.0V and up to 10A at the output. The circuit can be powered from a +36V to +72V or a -36V to -72V DC source. The user must supply at least 220F of bulk storage capacitor at the input terminals (VIN+, VIN-). The capacitor should be rated for 100V and be able to carry 1.5A of ripple current. The 50W forward converter achieves high efficiency by using a single transistor topology. Current limiting protects the converter against short circuits at the output. A current sense resistor (R6) senses the current through the primary of the transformer (T1) and the switching transistor (N1) and turns off the transistor when the trip level of 500mV is reached. The surfacemount transformer features a reset winding that, along with diode (D5), recovers the magnetic energy stored in the core and feeds it back to the input (VIN+). The transformer provides galvanic isolation up to 1500V. Shunt regulator (U3) along with feedback resistors (R11, R12) provide voltage feedback to the primary side through optocoupler (U2). Remote output voltage sensing is provided by the +SENSE and -SENSE for accurate output voltage regulation across the load. The softstart allows the output voltage to slowly ramp up in a controlled manner within 20ms. The MAX5015 controller switches at a fixed 275kHz frequency, and the duty cycle is varied to control energy transfer to the output.
Evaluating Other Output Voltages, Current Limits, and Soft-Starts
VOUT Output Voltage The MAX5015 EV kit's output (VOUT) is set to +5.0V by feedback resistors (R11, R12). To generate output voltages other than +5.0V (+3.2V to +5.0V), select different voltage-divider resistors (R11, R12). Resistor R11 is typically chosen to be less than 25k. Using the desired output voltage, resistor R12 is then found by the following equation:
R12 = [R11 / ((VOUT / VREF) - 1)] where VREF = 1.24V The maximum output current should be limited to less than 10A. The usable output voltage range for the EV kit is +3.2V to +5.0V. Additionally, ICs U2, U3, and resistor R9 limit the minimum output voltage (VOUT) to +3.2V.
Current Limiting
The EV kit features current limiting for the transformer primary current. The MAX5015 IC turns off the switching MOSFET (N1) when the voltage at the CS pin of the device reaches 465mV. A current sense resistor (R6, 0.1) limits the peak primary current to 4.65A (465mV / 0.1 = 4.65A). This will limit short-circuit current on the secondary output (VOUT) to 13A typically. To evaluate lower current limits, the current sense resistor (R6) must
_______________________________________________________________________________________
3
MAX5015 Evaluation Kit Evaluates: MAX5015
be replaced with a surface-mount resistor (1206 size) as determined by the following equation: R6 = VSENSE / ((NS / NP) x (1.2 x IOUTMAX)) where VSENSE = 0.5V, NS = 5, NP = 14, and IOUTMAX = maximum DC output current (10A as configured).
Soft-Start
The MAX5015 EV kit limits the ramp time to full current limit and duty cycle with a soft-start feature. Capacitor C2 (0.01F), sets the ramp time to 20ms. To evaluate other soft-start ramp times replace capacitor C2 with another surface mount capacitor (0805 size) as determined by the following equation: C2 (F) = soft-start time (s) / (0.45s/F)
1V/div 0V
4ms/div
Forward Converter Waveforms
EFFICIENCY (%) vs. OUTPUT CURRENT (A)
90.0 80.0 70.0 EFFICIENCY (%) 60.0 50.0 40.0 30.0 20.0 10.0 0 0 2 4 6 8 10 12 14
Figure 2. Output Voltage Transient at Power-Up. VIN+ = 48V, IOUT = 5A
20V/div
0V 1s/div
OUTPUT CURRENT (A)
Figure 1. Efficiency vs. Output Current. VIN+ = 48V
Figure 3. MOSFET N1, Drain-Source Voltage Waveform, VIN+ = 48V
4
_______________________________________________________________________________________
MAX5015 Evaluation Kit Evaluates: MAX5015
D1 OPEN Q1 VDD VIN 2 1
R1 OPEN
VIN D5 T1 3 12T 4 11, 12 5 5T 6 1 5T R3 20 C12 0.001F 200V C16 0.0047F 250VAC 3 1 D4 2
3
D3 C8 0.047F
L1 4.7H VOUT C7 560F 6.3V C13 560F 6.3V C14 560F 6.3V C15 0.1F SGND
SHORT COLLECTION TO EMITTER
VIN+ VINC4 0.68F C5 0.68F C6 0.68F R7 1 2 1 3 SHDN
8, 9
14T 2
1 8 C9 10F VDD VCC C1 0.1F 2 C11 0.33F 3 R13 4.75k 1%
V+ VCC
NDRV GND SS/SHDN
7 6 4
N1
R8 499 1% CS C3 OPEN VOUT
VDD
U1 MAX5015
C2 0.01F
R6 0.1 1% R16 51
OPTO
CS
5
CS R9 150
+SENSE 6 R10 SHORT C17 0.022F D2 5 OPEN R5 240k U2 1 C10 0.1F 3 U3 5 4 R12 8.35k 1% -SENSE R11 25.5k 1%
R15 3.32k 1%
7
2
R17 51
Figure 4. MAX5015 EV Kit Schematic
_______________________________________________________________________________________
5
MAX5015 Evaluation Kit Evaluates: MAX5015
1.0"
1.0"
Figure 5. MAX5015 EV Kit Component Placement Guide-- Component Side
Figure 6. MAX5015 EV Kit PC Board Layout--Component Side
1.0"
1.0"
Figure 7. MAX5015 EV Kit PC Board Layout--Inner Layer, Ground Plane 6
Figure 8. MAX5015 EV Kit PC Board Layout--Inner Layer, Power Plane
_______________________________________________________________________________________
MAX5015 Evaluation Kit Evaluates: MAX5015
1.0"
1.0"
Figure 9. MAX5015 EV Kit PC Board Layout--Solder Side
Figure 10. MAX5015 EV Kit Component Placement Guide-- Solder Side
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 7 (c) 2002 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.

▲Up To Search▲

Price & Availability of MAX5015EVKIT

	To Download MAX5015EVKIT Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .