|
|
PDF FAN5232 Data sheet ( Hoja de datos )
| Número de pieza | FAN5232 | |
| Descripción | Adjustable PWM Buck Controller for LCD PCs | |
| Fabricantes | Fairchild Semiconductor | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de FAN5232 (archivo pdf) en la parte inferior de esta página. Total 9 Páginas | ||
|
No Preview Available !
www.fairchildsemi.com
FAN5232
Adjustable PWM Buck Controller for LCD PCs
Features
• Three outputs: Adjustable Buck, 3.3V-Always,
5V-Always
• Adjustable synchronous switcher, 5V – 80% Vin
• 1% internal reference precision
• Current mode with voltage feed-forward
• Precision current limit option
• Charge pump works at all loads
• No shoot-through current
• Independent shutdown pins for ACPI
• Power Good, input UVLO, output OV
• 5.6V to 24V input voltage range
Applications
• LCD PCs
• Notebook PCs and PDAs
• Hand-held portable instruments
Description
The FAN5232 is a high efficiency and high precision DC/DC
controller for PCs. It has a synchronous switcher whose
output can be adjusted from 5V up to 80% of Vin. It also has
two linear regulators for standby, 3.3V and 5V. The PWM
utilizes both input and output voltage feedback in a
current-mode control, allowing for fast and stable loop
response over a wide range of input and output variations.
Synchronous switching provides best efficiency over a wide
range of loads. Current sense based on MOSFET RDS,on
gives maximum efficiency, while also permitting use of an
optional sense resistor for high precision.
The FAN5232 is available in a 14 pin TSSOP package.
Block Diagram
Vin = 16–22V
3.3V-Always
5V-Always
SDWN
SDNADJ
PWRGD
1 14
2 13
3 12
FAN5232
4 11
5 10
69
78
12V @ 8A
+
REV. 1.1.1 10/7/02
1 page  
PRODUCT SPECIFICATION
Table 1. RC5232 Application Bill of Materials
Reference Manufacturer, Part #
Quantity Description
C1 SANYO
25SV47M
1 47µF, 25V
C2-5
Any
4 100nF, 50V
C6 AVX
1 220µF, 16V
TPSE227M016#0100
R1 Any
1 10KΩ, 1%
R2, R4
Any
2 4.7Ω, 1%
R3, R5
Any
2 1KΩ, 1%
R6 Any
1 715Ω, 1%
D1 Fairchild
MBR0540L
1 500mA, 40V Schottky
L1 Coiltronics
UP2B-1R5
1 1.5µH, 8.3A
Q1 Fairchild
FDS6690A
1 30V N-channel MOSFET
Q2 Fairchild
FDS6680S
1 30V N-channel MOSFET
with Integrated Schottky
U1 Fairchild FAN5232
1 Controller
FAN5232
Comments
OSCON, Irms = 3.5A
Ceramic
Tantalum, ESR=100mΩ
R < 8mΩ
R = 20mΩ @ VGS = 4.5V
R = 17mΩ @ VGS = 4.5V
Application Information
Overview
The FAN5232 is a high efficiency and high precision DC/DC
controller for LCD PCs and portable applications. It provides
a switcher controller capable of generating a voltage between
5V to 80% of Vin, and a 5V and a 3.3V linear regulator for
standby applications. The controller has a power good output
and an enable/soft start to permit proper system sequencing.
Initialization
The FAN5232 automatically initializes upon receipt of input
power. The Power-on Reset (POR) function continually
monitors the input supply voltage on the VCC pin and
initiates soft start operation after the input supply voltage
exceeds 4.5V. Should this voltage drop below 4.0V, POR
disables the chip.
Soft Start
When soft start is initiated by POR, and if the SDWN pin is
not held low, the voltage on the SDNADJ pin begins ramping
up, with the rate of rise set by the external capacitor on the
pin. Below 700mV, the output is off. Between 700mV and
1.6V, the output is allowed to linearly ramp up. Above 1.6V,
the output is fully enabled, and regulates.
Shutdown
There are two separate shutdown pins to provide output
power control – SDWN, and SDNADJ. Taking the SDNADJ
pin low will disable the switcher output and reset the output’s
internal latches for short circuit, under-voltage and over-volt-
age. Taking the SDWN pin low puts the entire chip in shut-
down. Each of the SDN pins has an internal
pull-up.
Switcher Architecture
Overview
The switcher output of the FAN5232 is generated from the
unregulated input (battery) voltage using a synchronous buck
converter. Both high-side and low-side MOSFETs are
N-channel.
The converter has pins for current sensing using the low-side
MOSFET RDS,on; a pin for voltage-sense feedback; a pin
that enables the converter and permits soft-start; a power
good pin; and a pin for generating the boost voltage to drive
the high-side MOSFET.
REV. 1.1.1 10/7/02
5
5 Page | ||
| Páginas | Total 9 Páginas | |
| PDF Descargar | [ Datasheet FAN5232.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| FAN5230 | System Electronics Regulator for Mobile PCs | Fairchild Semiconductor |
| FAN5231 | Precision Dual PWM Controller And Linear Regulator for Notebook CPUs | Fairchild Semiconductor |
| FAN5232 | Adjustable PWM Buck Controller for LCD PCs | Fairchild Semiconductor |
| FAN5233 | System Electronics Regulator for Mobile PCs | Fairchild Semiconductor |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |