FAN2103_08 FAIRCHILD | Alldatasheet
Document overview
- Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
- PDF pages: 14
Technical content
Features
3A Output Current Over 95% Efficiency Fully Synchronous Operation with Integrated Schottky Diode on Low-side MOSFET Boosts Efficiency Programmable Frequency Operation (200KHz to 600KHz) Power-good Signal Accepts Ceramic Capacitors on Output External Compensation for Flexible Design Wide Input Range: 3V to 24V Output Voltage Range: 0.8V to 90%VIN Input Under-voltage Lockout Programmable Over-current Limit Under-voltage, Over-voltage, and Thermal Protections 5x6mm, 25-pin, 3-pad MLP
Applications
Graphics Cards Battery-powered Equipment Set-top Boxes Point-of-load Regulation Servers
Description
The FAN2103 TinyBuck™ is an easy-to-use, cost- and space-efficient, 3A synchronous buck solution. It enables designers to solve high current requirements in a small area with minimal external components. External compensation, programmable switching frequency, and current limit features allow for design optimization and flexibility. The summing current mode modulator uses lossless current sensing for current feedback and over-current, and includes voltage feedforward. Fairchild’s advanced BiCMOS power process, combined with low R DS(ON) internal MOSFETs and a thermally efficient MLP package provide the ability to dissipate high power in a small package. Output over-voltage, under-voltage, and thermal shutdown protections plus power-good, help protect the devices from damage during fault conditions. Related Application Notes AN-5067 – PCB Land Pattern Design and Surface Mount Guidelines for MLP Packages
Ordering Information
Temperature Range Package Eco Status Packing Method FAN2103MPX -10°C to 85°C 25-Pin Molded Leadless Package (MLP) 5x6mm Green Tape and Reel FAN2103EMPX -40°C to 85°C 25-Pin Molded Leadless Package (MLP) 5x6mm Green Tape and Reel For Fairchild’s definition of “green” please visit: http://www.fairchildsemi.com/company/green/rohs_green.html .
Figure 3. MLP 5x6mm Pin Conf iguration (Bottom View) P2, 2-5 VIN Power Input Voltage. Connect to the main input power source. P3, 21-23 PGND Power Ground. Power return and Q2 source.
1 BOOT
13 PGOOD
functioning normally. When a latched fault occurs , EN is discharged by a current sink. 15 VCC Input Bias Supply for IC. The IC’s logic and analog circuitry are powered from this pin. this pin. Tie this pin to the ground island/plane through the lowest impedance connection. limit trip threshold lower than the default setting. 19 FB Output Voltage Feedback. Connect through a resistor divider to the output voltage. 24 NC No Connect. This pin is not used. amplitude and provides voltage feedforward functionality.
© 2007 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN2103 Rev. 1.0.5 4 FAN2103 — TinyBuck™ 3A, 24V Input, Integrated Synchronous Buck Regulator Absolute Maximum Ratings Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be operable above the recommended operating conditions and stressing the parts to these levels is not recommended. In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability. The absolute maximum ratings are stress ratings only. Parameter Conditions Min. Max. Unit VIN to PGND 28 V VCC to AGND AGND = PGND 6 V BOOT to PGND 35 V BOOT to SW -0.3 6.0 V SW to PGND Transient (t < 20ns, f < 600KHz) -5 30 V All other pins -0.3 V CC+0.3 V Human Body Model, JESD22-A114 2 ESD Charged Device Model, JESD22-C101 2 kV Recommended Operating Conditions The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ens ure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to absolute maximum ratings. Symbol Parameter Conditions Min. Typ. Max. Unit VCC Bias Voltage VCC to AGND 4.5 5.0 5.5 V VIN Supply Voltage VIN to PGND 3 24 V FAN2103M -10 +85 °C TA Ambient Temperature FAN2103EM -40 +85 °C TJ Junction Temperature +125 °C Thermal Information Symbol Parameter Min. Typ. Max. Unit TSTG Storage Temperature -65 +150 °C TL Lead Soldering Temperature, 10 Seconds +300 °C TVP Vapor Phase, 60 Seconds +215 °C TI Infrared, 15 Seconds +220 °C P1 (Q2) 4 °C/W P2 (Q1) 7 °C/W θJC Thermal Resistance: Junction-to-Case P3 4 °C/W θJ-PCB Thermal Resistance: Junction-to-Mounting Surface 35 (1) °C/W PD Power Dissipation, T A = 25°C 2.8 (1) W Note: 1. Typical thermal resistance when mounted on a four-layer, two-ounce PCB, as shown in Figure 25. Actual results are dependent on mounting method and surface related to the design.
© 2007 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN2103 Rev. 1.0.5 5 FAN2103 — TinyBuck™ 3A, 24V Input, Integrated Synchronous Buck Regulator Electrical Specifications Recommended operating conditions are the result of using the circuit shown in Figure 1 unless otherwise noted. Parameter Conditions Min. Typ. Max. Unit Power Supplies SW = Open, FB = 0.7V, VCC = 5V, fSW = 600KHz 8 12 mA VCC Current Shutdown: EN = 0, VCC = 5V 7 10 µA Rising VCC 4.1 4.3 4.5 V VCC UVLO Threshold Hysteresis 300 mV Oscillator RT = 50KΩ 255 300 345 KHz Frequency RT = 24KΩ 540 600 660 KHz Minimum On-Time(2) 50 65 ns Ramp Amplitude, pk–pk 16VIN, 1.8VOUT, RT = 30KΩ, RRAMP = 200KΩ 0.53 V Minimum Off-Time(2) 100 150 ns Reference FAN2103M, 25°C 794 800 806 mV Reference Voltage (VFB) FAN2103EM, 25°C 795 800 805 mV FAN2103M, -10 to +85°C 50 PPM Temperature Coefficient FAN2103EM, -40 to +85°C 70 PPM Error Amplifier DC Gain(2) 80 85 dB Gain Bandwidth Product(2) 12 15 MHz Output Voltage (VCOMP) VCC = 5V 0.4 3.2 V Output Current, Sourcing V CC = 5V, VCOMP = 2.2V 1.5 2.2 mA Output Current, Sinking V CC = 5V, VCOMP = 1.2V 0.8 1.2 mA FB Bias Current V FB = 0.8V, 25°C -850 -650 -450 nA Protection and Shutdown Current Limit R ILIM open 3.8 5.0 7.0 A ILIM Current 25°C, V CC = 5V 9 10 11 µA Over-Temperature Shutdown +160 °C Over-Temperature Hysteresis Internal IC Temperature +30 °C Over-Voltage Threshold 2 Consecutive Clock Cycles 110 115 120 %V OUT Under-Voltage Shutdown 16 Consecutive Clock Cycles 68 73 78 %V OUT Fault Discharge Threshold Measured at FB Pin 250 mV Fault Discharge Hysteresis Measured at FB Pin (V FB ~500mV) 250 mV Soft-Start VOUT to Regulation (T0.8) 5.3 ms Fault Enable/SSOK (T1.0) Frequency = 600KHz 6.7 ms Note: 2. Specifications guaranteed by design and characterization; not production tested.
© 2007 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN2103 Rev. 1.0.5 6 FAN2103 — TinyBuck™ 3A, 24V Input, Integrated Synchronous Buck Regulator Electrical Specifications (Continued) Recommended operating conditions are the result of using the circuit shown in Figure 1 unless otherwise noted. Parameter Conditions Min. Typ. Max. Unit Control Functions EN Threshold, Rising 1.35 2.00 V EN Hysteresis 250 mV EN Pull-up Resistance 800 KΩ EN Discharge Current Auto-restart Mode 1 µA FB OK Drive Resistance 800 Ω FB < VREF -14 -11 -8 %V REF PGOOD Threshold (Compared to VREF) FB > VREF +7 +10 +13 %V REF PGOOD Output Low I OUT < 2mA 0.4 V
before releasing the internal soft-start ramp (SS). voltage latched fault occurs. 1.0V (T1.0), the “Fault Latch” is inhibited. IN before VCC reaches its UVLO threshold. Soft-start time is a function of oscillator frequency.
3200 CLKs
4000 CLKs
2400 CLKs
Figure 21. Soft-Start Timing Diagram does not "ratchet" up during the soft-start cycle. and provide gate-drive energy and controller power. supply current is frequency and voltage dependent. where frequency (f) is expressed in KHz. Connect RBIAS between FB and AGND. where RT is expressed in KΩ. where frequency (f) is expressed in KHz. The regulator does not start if RT is left open.
A) DIMENSIONS ARE IN MILLIMETERS. X & Y AXIS EXCEPT WHERE DEPOPULATED. Figure 26. 5x6mm Molded Leadless Package (MLP) the warranty therein, which covers Fairchild products.
© 2007 Fairchild Semiconductor Corporation www.fairchildsemi.com FAN2103 Rev. 1.0.5 14 FAN2103 — TinyBuck™ 3A, 24V Input, Integrated Synchronous Buck Regulator