|
|
PDF PAM2306 Data sheet ( Hoja de datos )
| Número de pieza | PAM2306 | |
| Descripción | DUAL HIGH-EFFICIENCY PWM STEP-DOWN DC-DC CONVERTER | |
| Fabricantes | Diodes | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de PAM2306 (archivo pdf) en la parte inferior de esta página. Total 15 Páginas | ||
|
No Preview Available !
A Product Line of
Diodes Incorporated
PAM2306
DUAL HIGH-EFFICIENCY PWM STEP-DOWN DC-DC CONVERTER
Description
The PAM2306 is a dual step-down current-mode, DC-DC converter.
At heavy load, the constant frequency PWM control provides
excellent stability and transient response. To ensure the longest
battery life in portable applications, the PAM2306 provides a power -
saving Pulse-Skipping Modulation (PSM) mode to reduce quiescent
current under light load operation.
The PAM2306 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 dual output
voltages are available for 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 0.1A. Other key features
include under-voltage lockout to prevent deep battery discharge.
Pin Assignments
Features
Efficiency up to 96%
Only 40μA (typ per channel) Quiescent Current
Output Current: Up to 1A per Channel
Internal Synchronous Rectifier
1.5MHz Switching Frequency
Soft Start
Under-Voltage Lockout
Short Circuit Protection
Thermal Shutdown
Small 12L WDFN3x3 Package
Pb-Free Package and RoHS Compliant
Applications
Cellular Phone
Portable Electronics
Personal Information Appliances
Wireless and DSL Modems
MP3 Players
Typical Applications Circuit
PAM2306
Document number: DS36392 Rev. 1 - 2
V
OUT
VREF1
Rx1
Rx2
Figure 1. Adjustable Voltage Regulator
1 of 15
www.diodes.com
November 2012
© Diodes Incorporated
1 page  
A Product Line of
Diodes Incorporated
PAM2306
Typical Performance Characteristics (@TA = +25°C, CIN = 10µF, CO = 10µF, L = 4.7µH, unless otherwise specified.)
PAM2306
Document number: DS36392 Rev. 1 - 2
5 of 15
www.diodes.com
November 2012
© Diodes Incorporated
5 Page 
A Product Line of
Diodes Incorporated
PAM2306
Application Information (cont.)
Thermal Consideration (cont.)
For the condition where the step-down converter is in dropout at 100% duty cycle, the total device dissipation reduces to:
PD IO2 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)
JA
TA
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 WDFN3X3 is 60°C/W.
The maximum power dissipation at TA = +25°C can be calculated by following formula:
PD = (125°C - 25°C)/60°C/W = 1.66W
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
1.2V
1.5V
1.8V
2.5V
3.3V
R1
100k
150k
200k
380k
540k
R2
100k
100k
100k
120k
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 PAM2306 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 Prectection
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.
Thermal Shutdown
When the die temperature exceeds +150°C, a reset occurs and the reset remains until the temperature decrease to +120°C, at which time the
circuit can be restarted.
PAM2306
Document number: DS36392 Rev. 1 - 2
11 of 15
www.diodes.com
November 2012
© Diodes Incorporated
11 Page | ||
| Páginas | Total 15 Páginas | |
| PDF Descargar | [ Datasheet PAM2306.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| PAM2301 | 800mA Step-Down DC-DC Converters |  Power Analog Micoelectronics |
| PAM2301 | 800mA STEP-DOWN DC-DC CONVERTER | Diodes |
| PAM2303 | 3A STEP-DOWN DC-DC CONVERTER | Diodes |
| PAM2304 | 1A STEP-DOWN DC-DC CONVERTER | Diodes |
| 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 |