FAN5236 Fairchild Semiconductor, FAN5236 Datasheet
FAN5236
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FAN5236 Summary of contents
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... DDR chips. The buffered reference voltage required by this type of memory is also provided. The FAN5236 monitors these outputs and generates separate PGx (power good) signals when the soft-start is completed and the output is within ± ...
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... Part Number Temperature Range FAN5236MTCX -10 to +85°C Block Diagrams +5 VCC +5 ILIM1 DDR +5 PG2/REF 1.25V © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 Package 28-Lead Thin-Shrink Small-Outline Package (TSSOP) VCC FAN5236 ILIM1 PWM 1 DDR ILIM2/ REF2 PWM 2 Figure 1. Dual-Output Regulator V FAN5236 PWM 1 ...
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... Current Limit 1. A resistor from this pin to GND sets the current limit. 12 SS1 Soft Start. A capacitor from this pin to GND programs the slew rate of the converter during initialization. During initialization, this pin is charged with a 5mA current source. 17 SS2 © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 AGND VCC 1 28 LDRV1 LDRV2 2 ...
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... VCC. This pin powers the chip as well as the LDRV buffers. The IC starts to operate when 28 VCC voltage on this pin exceeds 4.6V (UVLO rising) and shuts down when it drops below 4.3V (UVLO falling). © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 Description reference. DDQ outside a ±10% ...
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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 © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 Parameter Parameter Min. 4.75 5 Min. Max. 6 6.5 -0.3 V +0.3 CC -40 +150 -65 +150 +300 Typ ...
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... VOUT Pin Input Impedance UVLO Under-Voltage Shutdown TSD UVLO Over-Voltage Threshold I Over-Current Threshold SNS Output Drivers HDRV Output Resistance LDRV Output Resistance © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 Conditions LDRV, HDRV Open, V Forced Above SEN Regulation Point Shutdown (EN- 24V ...
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... OSC VIN CLK VSEN EA FPWM/VOUT SS Reference and PGOOD Soft Start REF2 © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 (Continued) Conditions % of Set Point, 2µs Noise Filter % of Set Point, 2µs Noise Filter IPG = 4mA PULLUP ≤10mA DDR = 1, 0mA < I REF2OUT FPWM Connected to Output ...
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... Suitable for typical notebook computer application of 4A continuous, 6A peak for V above 6A is required, use single SO-8 packages. For more information, refer to the Power MOSFET Selection Section and use AN-6002 for design calculations. © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 VIN 14 BOOT1 ...
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... Dual MOSFET with Schottky 30 DDR Controller Note currents above 4A continuous are required, use single SO-8 packages. For more information, refer to the Power MOSFET Selection Section and AN-6002 for design calculations. © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 VIN C1 14 BOOT1 6 Q1A HDRV1 ...
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... The Hysteretic Mode can be inhibited independently for each channel if variable frequency operation is not desired. The FAN5236 can be configured to operate as a complete DDR solution. When the DDR pin is set HIGH, the second channel provides the capability to track the output voltage of the first channel ...
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... Initialization and Soft Start Assuming EN is HIGH, FAN5236 is initialized when V exceeds the rising UVLO threshold. Should V below the UVLO threshold, an internal power-on reset function disables the chip. The voltage at the positive input of the error amplifier is limited by the voltage at the SS pin, which is charged with a 5μ ...
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... ON ) ⎝ ⎠ © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 Because of the different control mechanisms, the value of the load current where transition into CCM operation takes place is typically higher compared to the load level at which transition into Hysteretic Mode occurs. Hysteretic Mode can be disabled by setting the FPWM pin LOW ...
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... Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 Frequency Loop Compensation of the FET, as shown Due to the implemented current-mode control, the modulator has a single-pole response with -1 slope at and I ...
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... ILIM det is again reached, the over-current protection latch is set, disabling the © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 regulator. If ILIM det does not occur between cycles nine and sixteen, normal operation is restored and the output filter over-current circuit resets itself ...
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... L ≈ 6 µH © 2002 Fairchild Semiconductor Corporation FAN5236 • Rev. 1.3.2 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. The output capacitor requirements are usually dictated by ESR, inductor ripple current (Δ ...
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... Losses in a MOSFET are the sum of its switching (P and conduction (P ) losses. COND In typical applications, the FAN5236 converter’s output voltage is low with respect to its input voltage. Therefore, the lower MOSFET (Q2) is conducting the full load current for most of the cycle. Q2 should ...
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... For the high-side MOSFET high as 20V in a typical portable application. Care should be taken to include the delivery of the MOSFET’s gate power (PGATE) in calculating the power dissipation required for the FAN5236: = × × ATE where Q is the total gate charge to reach V ...
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... 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’s online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/. © 2002 Fairchild Semiconductor Corporation FAN5236 Rev. 1.3.2 Figure 19. 28-Lead, Thin Shrink Outline Package 18 www.fairchildsemi.com ...
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... Fairchild Semiconductor Corporation FAN5236 Rev. 1.3.2 19 www.fairchildsemi.com ...