FAN5234QSCX Fairchild Semiconductor, FAN5234QSCX Datasheet
FAN5234QSCX
Specifications of FAN5234QSCX
FAN5234QSCX_NL
FAN5234QSCX_NLTR
FAN5234QSCX_NLTR
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FAN5234QSCX Summary of contents
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... Operating Part Number Temperature Range FAN5234MTCX -10 to +85°C © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 Description The FAN5234 PWM controller provides high efficiency and regulation with an adjustable output from 0.9V to 5.5V required to power I/O, chip-sets, memory banks, or peripherals in high-performance notebook computers, ...
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... Typical Application VIN (BAT TERY 24V VCC + ILIM SS1 FPWM 16 R4 AGND 8 PGOOD 2 Block Diagram © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 VIN Q1A FA N5 234 HDRV Q1B LDRV 10 PGND 9 ISNS 12 VSEN 6 VOUT 5 Figure 1. 1.18V Output Regulator Figure 2. Block Diagram ...
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... MOSFET. 15 BOOT BOOT. Positive supply for the upper MOSFET driver. Connect as shown in Figure 2. Forced PWM Mode. When logic HIGH, inhibits the regulation from entering Hysteretic 16 FPWM Mode. © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 VIN FPWM 1 16 PGOOD BOOT ...
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... Fairchild does not recommend exceeding them or designing to Absolute Maximum Ratings. Symbol V V Supply Voltage Supply Voltage Ambient Temperature A Θ Thermal Resistance, Junction to Ambient JA © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 Parameter Parameter Min. 4.75 4 Min. Max. 6 6.5 -0.3 V +0.3 CC -10 +150 ...
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... Under-Voltage Shutdown TSD I Over-Current Threshold SNS UVLO Over-Voltage Threshold Output Drivers HDRV Output Resistance LDRV Output Resistance © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 Conditions Min. LDRV, HDRV Open; V Forced Above SEN Regulation Point Shutdown (EN-0) VIN Pin = Input Voltage ...
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... Upper Threshold PGOOD Output Low Leakage Current Soft-Start Voltage, PGOOD Enabled EN, FPWM Inputs V Input High INH V Input Low INL © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 (Continued) Conditions % of Set Point, 2µs Noise Filter % of Set Point, 2µs Noise Filter I = 4mA PGOOD V ...
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... µF. 0.9 SS © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 When SS reaches 1.5V, the power-good outputs are enabled and Hysteretic Mode is allowed. The converter is forced into PWM Mode during soft-start. Operation Mode Control The mode-control circuit changes the converter’s mode ...
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... MAX ) ⎜ ⎟ = − R 100 ⎜ ⎟ SENSE μ 150 A ⎝ ⎠ © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 PWMMode HystereticMode Setting the Current Limit A ratio of I established when a 0.9V internal reference drives the ILIM pin LIM I Since the tolerance on the current limit is largely ...
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... The adaptive gate control logic translates the internal PWM control signal into the MOSFET gate drive signals, providing necessary amplification, level shifting, and shoot-through protection. It also has functions that help optimize the IC performance over a wide range of © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0 ISNS 4 ...
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... drops below the under-voltage threshold, the OUT chip shuts down immediately. © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 Over-Current Sensing If the circuit's current-limit signal (“I is HIGH at the beginning of a clock cycle, a pulse- skipping circuit is activated and HDRV is inhibited. The circuit continues to pulse skip in this manner for the next eight clock cycles ...
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... SW Therefore; L ≈ 8 µH © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 Output Capacitor Selection The output capacitor serves two major functions in a switching power supply. Along with the inductor, it filters the sequence of pulses produced by the switcher and it supplies the load transient currents ...
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... Figure 9. Switching Losses and ISS HDRV SW Figure 10. Drive Equivalent Circuit © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 The driver’s impedance and C period is controlled by the driver's impedance and Q vs. time Since most current assumption for the driver to simplify the ). calculation ...
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... It is not recommended to use high density interconnect systems, or micro-vias, on these signals. The use of blind or buried vias should be limited to the low-current signals only. The use of normal thermal vias is at the discretion of the designer. © 2004 Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 Qty. Ref. Vendor ...
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... Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor’ ...
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... Fairchild Semiconductor Corporation FAN5234 • Rev. 2.0.0 15 www.fairchildsemi.com ...