DataSheet26.com

5236QSCX PDF даташит

Спецификация 5236QSCX изготовлена ​​​​«Fairchild Semiconductor» и имеет функцию, называемую « FAN5236QSCX».

Детали детали

Номер произв 5236QSCX
Описание FAN5236QSCX
Производители Fairchild Semiconductor
логотип Fairchild Semiconductor логотип 

20 Pages
scroll

No Preview Available !

5236QSCX Даташит, Описание, Даташиты
www.DataSheet4U.com
www.fairchildsemi.com
FAN5236
Dual Mobile-Friendly DDR / Dual-output PWM Controller
Features
• Highly flexible dual synchronous switching PWM
controller includes modes for:
– DDR mode with in-phase operation for reduced
channel interference
– 90˚ phase shifted two-stage DDR Mode for reduced
input ripple
– Dual Independent regulators 180° phase shifted
• Complete DDR Memory power solution
– VTT Tracks VDDQ/2
– VDDQ/2 Buffered Reference Output
• Lossless current sensing on low-side MOSFET or
precision over-current using sense resistor
• VCC Under-voltage Lockout
• Converters can operate from +5V or 3.3V or Battery
power input (5 to 24V)
• Excellent dynamic response with Voltage Feed-Forward
and Average Current Mode control
• Power-Good Signal
• Also supports DDR-II and HSTL
• Light load Hysteretic mode maximizes efficiency
• QSOP28, TSSOP28
Applications
• DDR VDDQ and VTT voltage generation
• Mobile PC dual regulator
• Server DDR power
• Hand-Held PC power
General Description
The FAN5236 PWM controller provides high efficiency and
regulation for two output voltages adjustable in the range
from 0.9V to 5.5V that are required to power I/O, chip-sets,
and memory banks in high-performance notebook comput-
ers, PDAs and Internet appliances. Synchronous rectification
and hysteretic operation at light loads contribute to a high
efficiency over a wide range of loads. The hysteretic mode of
operation can be disabled separately on each PWM converter
if PWM mode is desired for all load levels. Efficiency is even
further enhanced by using MOSFET’s RDS(ON) as a current
sense component.
Feed-forward ramp modulation, average current mode con-
trol scheme, and internal feedback compensation provide
fast response to load transients. Out-of-phase operation with
180 degree phase shift reduces input current ripple. The con-
troller can be transformed into a complete DDR memory
power supply solution by activating a designated pin. In
DDR mode of operation one of the channels tracks the out-
put voltage of another channel and provides output current
sink and source capability — features essential for proper
powering of 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 ±10% of its set point. A built-in
over-voltage protection prevents the output voltage from
going above 120% of the set point. Normal operation is auto-
matically restored when the over-voltage conditions go
away. Under-voltage protection latches the chip off when
either output drops below 75% of its set value after the soft-
start sequence for this output is completed. An adjustable
over-current function monitors the output current by sensing
the voltage drop across the lower MOSFET. If precision cur-
rent-sensing is required, an external current-sense resistor
may optionally be used.
REV. 1.1.7 4/4/03









No Preview Available !

5236QSCX Даташит, Описание, Даташиты
www.DataSheet4U.com
PRODUCT SPECIFICATION
Generic Block Diagrams
+5 VCC
FAN5236
ILIM1
PWM 1
DDR
ILIM2/
REF2
PWM 2
VIN (BATTERY)
= 5 to 24V
Q1
L OUT1
VOUT1
= 2.5V
COUT1
Q2
Q3
L OUT2
VOUT2
= 1.8V
COUT2
Q4
+5 VCC
ILIM1
+5 DDR
PG2/REF
1.25V
Figure 1. Dual output regulator
FAN5236
PWM 1
PWM 2
VIN (BATTERY)
= 5 to 24V
Q1
L OUT1
Q2
VDDQ
= 2.5V
COUT1
R
Q3
L OUT2
VTT =
VDDQ/2
Q4 COUT2
R
ILIM2/REF2
Figure 2. Complete DDR Memory Power Supply
FAN5236
2 REV. 1.1.7 4/4/03









No Preview Available !

5236QSCX Даташит, Описание, Даташиты
www.DataSheet4U.com
FAN5236
Pin Configurations
AGND
LDRV1
PGND1
SW1
HDRV1
BOOT1
ISNS1
EN1
FPWM1
VSEN1
ILIM1
SS1
DDR
VIN
1 28
2 27
3 26
4 25
5 24
6 23
7 22
8 FAN5236 21
9 20
10 19
11 18
12 17
13 16
14 15
VCC
LDRV2
PGND2
SW2
HDRV2
BOOT2
ISNS2
EN2
FPWM2
VSEN2
ILIM2/REF2
SS2
PG2/REF2OUT
PG1
QSOP-28 or TSSOP-28
θJA = 90°C/W
PRODUCT SPECIFICATION
Pin Definitions
Pin
Number Pin Name
1 AGND
2 LDRV1
27 LDRV2
3 PGND1
26 PGND2
4 SW1
25 SW2
5 HDRV1
24
6 BOOT1
23 BOOT2
7 ISNS1
22 ISNS2
8 EN1
21 EN2
9 FPWM1
20 FPWM2
10 VSEN1
19 VSEN2
11 ILIM1
12 SS1
17 SS2
13 DDR
Pin Function Description
Analog Ground. This is the signal ground reference for the IC. All voltage levels are
measured with respect to this pin.
Low-Side Drive. The low-side (lower) MOSFET driver output. Connect to gate of low-side
MOSFET.
Power Ground. The return for the low-side MOSFET driver. Connect to source of low-
side MOSFET.
Switching node. Return for the high-side MOSFET driver and a current sense input.
Connect to source of high-side MOSFET and low-side MOSFET drain.
High-Side Drive. High-side (upper) MOSFET driver output. Connect to gate of high-side
MOSFET.
BOOT. Positive supply for the upper MOSFET driver. Connect as shown in Figure 3.
Current Sense input. Monitors the voltage drop across the lower MOSFET or external
sense resistor for current feedback.
Enable. Enables operation when pulled to logic high. Toggling EN will also reset the
regulator after a latched fault condition. These are CMOS inputs whose state is
indeterminate if left open.
Forced PWM mode. When logic low, inhibits the regulator from entering hysteretic mode.
Otherwise tie to VOUT. The regulator uses VOUT on this pin to ensure a smooth
transition from Hysteretic mode to PWM mode. When VOUT is expected to exceed VCC,
tie to VCC.
Output Voltage Sense. The feedback from the outputs. Used for regulation as well as
PG, under-voltage and over-voltage protection and monitoring.
Current Limit 1. A resistor from this pin to GND sets the current limit.
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 5µA current source.
DDR Mode Control. High = DDR mode. Low = 2 separate regulators operating 180° out
of phase.
REV. 1.1.7 4/4/03
3










Скачать PDF:

[ 5236QSCX.PDF Даташит ]

Номер в каталогеОписаниеПроизводители
5236QSCX FAN5236QSCXFairchild Semiconductor
Fairchild Semiconductor

Номер в каталоге Описание Производители
TL431

100 мА, регулируемый прецизионный шунтирующий регулятор

Unisonic Technologies
Unisonic Technologies
IRF840

8 А, 500 В, N-канальный МОП-транзистор

Vishay
Vishay
LM317

Линейный стабилизатор напряжения, 1,5 А

STMicroelectronics
STMicroelectronics

DataSheet26.com    |    2020    |

  Контакты    |    Поиск