DataSheet.es    


PDF PAM2305 Data sheet ( Hoja de datos )

Número de pieza PAM2305
Descripción 1A STEP-DOWN DC-DC CONVERTER
Fabricantes Diodes 
Logotipo Diodes Logotipo



Hay una vista previa y un enlace de descarga de PAM2305 (archivo pdf) en la parte inferior de esta página.


Total 17 Páginas

No Preview Available ! PAM2305 Hoja de datos, Descripción, Manual

A Product Line of
Diodes Incorporated
PAM2305
1A STEP-DOWN DC-DC CONVERTER
Description
The PAM2305 is a step-down current-mode, DC-DC converter. At
heavy load, the constant frequency PWM control performs excellent
stability and transient response. To ensure the longest battery life in
portable applications, the PAM2305 provides a power-saving Pulse-
Skipping Modulation (PSM) mode to reduce quiescent current under
light load operation to save power.
The PAM2305 supports a range of input voltages from 2.5V to 5.5V,
allowing the use of a single Li+/Li-polymer cell, multiple Alkaline/NiMH
cell, USB, and other standard power sources. The output voltage is
adjustable from 0.6V to the input voltage, while the part number suffix
PAM2305-XX indicates pre-set output voltage of 3.3V, 2.8V, 2.5V,
1.8V, 1.5V, 1.2V or adjustable. All versions employ internal power
switch and synchronous rectifier to minimize external part count and
realize high efficiency. During shutdown, the input is disconnected
from the output and the shutdown current is less than 0.1µA. Other
key features include under-voltage lockout to prevent deep battery
discharge.
The PAM2305 is available in TSOT25, DFN2x2-6 Pin and QFN3x3-16
Pin packages.
Pin Assignments
Top View
TSOT25
Features
Efficiency up to 96%
Only 40µA(typ) Quiescent Current
Output Current: Up to 1A
Internal Synchronous Rectifier
1.5MHz Switching Frequency
Soft Start
Under-Voltage Lockout
Short Circuit Protection
Thermal Shutdown
5-pin Small TSOT25, DFN2x2-6 Pin and QFN3x3-16 Pin
Packages
Pb-Free Package
Applications
Cellular Phone
Portable Electronics
Wireless Devices
Cordless Phone
Computer Peripherals
Battery Powered Widgets
Electronic Scales
Digital Frame
PAM2305
Document number: DSxxxxx Rev. 2 - 6
1 of 17
www.diodes.com
January 2013
© Diodes Incorporated

1 page




PAM2305 pdf
A Product Line of
Diodes Incorporated
PAM2305
Typical Performance Characteristics (@TA = +25°C, CIN = 10µF, CO = 10µF, L = 4.7µH, unless otherwise specified.)
PAM2305
Document number: DSxxxxx Rev. 2 - 6
5 of 17
www.diodes.com
January 2013
© Diodes Incorporated

5 Page





PAM2305 arduino
A Product Line of
Diodes Incorporated
PAM2305
Application Information (cont.)
For the condition where the step-down converter is in dropout at 100% duty cycle, the total device dissipation reduces to:
PD = IO 2 RDS(ON)H + IQ VIN
Since RDS(ON), quiescent current, and switching losses all vary with input voltage, the total losses should be investigated over the complete input
voltage range. The maximum power dissipation depends on the thermal resistance of IC package, PCB layout, the rate of surrounding airflow
and temperature difference between junction and ambient. The maximum power dissipation can be calculated by the following formula:
PD = TJ(MAX) TA
θJA
Where TJ(max) is the maximum allowable junction temperature +125°C. TA is the ambient temperature and θJA is the thermal resistance from the
junction to the ambient. Based on the standard JEDEC for a two layers thermal test board, the thermal resistance θJA of TSOT25 package is
250°C/W, DFN2X2 102°C/W, and QFN3X3 68°C/W, respectively. The maximum power dissipation at TA = +25°C can be calculated by following
formula:
SOT-25 package:
PD =(125°C - 25°C)/250°C/W = 0.4W
DFN2*2 package:
PD =(125°C - 25°C)/102°C/W = 0.984W
QFN3*3 package:
PD =(125°C - 25°C)/68°C/W = 1.47W
Setting the Output Voltage
The internal reference is 0.6V (Typical). The output voltage is calculated as below:
VO
=
0.6
×
⎜⎛1 +
R1
R2
⎟⎞
The output voltage is given by Table 1.
Table 1: Resistor selection for output voltage setting.
VO R1 R2
1.2V
100k
100k
1.5V
150k
100k
1.8V
200k
100k
2.5V
380k
120k
3.3V
540k
120k
100% Duty Cycle Operation
As the input voltage approaches the output voltage, the converter turns the P-Channel transistor continuously on. In this mode the output voltage
is equal to the input voltage minus the voltage drop across the P-Channel transistor:
VOUT = VIN – ILOAD (RDS(ON) = RL)
where RDS(ON) = P-Channel switch ON resistance, ILOAD = Output current, RL = Inductor DC resistance.
UVLO and Soft-Start
The reference and the circuit remain reset until the VIN crosses its UVLO threshold.
The PAM2305 has an internal soft-start circuit that limits the in-rush current during start-up. This prevents possible voltage drops of the input
voltage and eliminates the output voltage overshoot. The soft-start acts as a digital circuit to increase the switch current in several steps to the P-
Channel current limit (1500mA).
Short Circuit Protection
The switch peak current is limited cycle-by-cycle to a typical value of 1500mA. In the event of an output voltage short circuit, the device operates
with a frequency of 400kHz and minimum duty cycle, therefore the average input current is typically 200mA.
PAM2305
Document number: DSxxxxx Rev. 2 - 6
11 of 17
www.diodes.com
January 2013
© Diodes Incorporated

11 Page







PáginasTotal 17 Páginas
PDF Descargar[ Datasheet PAM2305.PDF ]




Hoja de datos destacado

Número de piezaDescripciónFabricantes
PAM2301800mA Step-Down DC-DC ConvertersPower Analog Micoelectronics
Power Analog Micoelectronics
PAM2301800mA STEP-DOWN DC-DC CONVERTERDiodes
Diodes
PAM23033A STEP-DOWN DC-DC CONVERTERDiodes
Diodes
PAM23041A STEP-DOWN DC-DC CONVERTERDiodes
Diodes

Número de piezaDescripciónFabricantes
SLA6805M

High Voltage 3 phase Motor Driver IC.

Sanken
Sanken
SDC1742

12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters.

Analog Devices
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,
permitiéndote verlos en linea o descargarlos en PDF.


DataSheet.es    |   2020   |  Privacy Policy  |  Contacto  |  Buscar