|
|
PDF MCP1253 Data sheet ( Hoja de datos )
| Número de pieza | MCP1253 | |
| Descripción | (MCP1252 / MCP1253) Low Noise / Positive-Regulated Charge Pump | |
| Fabricantes | Microchip Technology | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de MCP1253 (archivo pdf) en la parte inferior de esta página. Total 20 Páginas | ||
|
No Preview Available !
MCP1252/3
Low-Noise, Positive-Regulated Charge Pump
Features:
• Inductorless, Buck/Boost, DC/DC Converter
• Low Power: 80 µA (Typical)
• High Output Voltage Accuracy:
- ±2.5% (VOUT Fixed)
• 120 mA Output Current
• Wide Operating Temperature Range:
- Industrial Temperature (I): -40°C to +85°C
- Extended Temperature (E): -40°C to +125°C
• Thermal Shutdown and Short-Circuit Protection
• Uses Small Ceramic Capacitors
• Switching Frequency:
- MCP1252: 650 kHz
- MCP1253: 1 MHz
• Low-Power Shutdown Mode: 0.1 µA (Typical)
• Shutdown Input Compatible with 1.8V Logic
• VIN Range: 2.0V to 5.5V
• Selectable Output Voltage (3.3V or 5.0V) or
Adjustable Output Voltage
• Space-Saving, 8-Lead MSOP
• Soft-Start Circuitry to Minimize In-Rush Current
• AEC-Q100 Qualified
Applications:
• White LED Backlighting
• Color Display Bias
• Local 3V-to-5V Conversions
• Flash Memory Supply Voltage
• SIM Interface Supply for GSM Phones
• Smart Card Readers
• PCMCIA Local 5V Supplies
Description:
The MCP1252/3 are inductorless, positive-regulated
charge pump DC/DC converters. The devices generate
a regulated fixed (3.3V or 5.0V) or adjustable output
voltage. They are specifically designed for applications
requiring low noise and high efficiency and are able to
deliver up to 120 mA output current. The devices allow
the input voltage to be lower or higher than the output
voltage, by automatically switching between buck/
boost operation.
The MCP1252 has a switching frequency of 650 kHz,
avoiding interference with sensitive IF bands. The
MCP1253 has a switching frequency of 1 MHz and
allows the use of smaller capacitors than the
MCP1252, thus saving board space and cost.
Both devices feature a power-good output that can be
used to detect out-of-regulation conditions. Extremely
low supply current and low external parts count (three
capacitors) make these devices ideal for small, battery-
powered applications. A shutdown mode is also pro-
vided for further power reduction. The MCP1252 and
MCP1253 feature thermal and short-circuit protection
and are offered in space-saving, 8-lead, MSOP
packages.
Package Types
MSOP (Fixed)
PGOOD
VOUT
VIN
GND
18
2 MCP1252 7
3 MCP1253 6
45
MSOP (Adjustable)
SELECT
SHDN
C+
C-
PGOOD
VOUT
VIN
GND
18
2 MCP1252 7
3 MCP1253 6
45
FB
SHDN
C+
C-
2002-2014 Microchip Technology Inc.
DS20001752C-page 1
1 page  
MCP1252/3
2.0 TYPICAL PERFORMANCE CURVES
Note:
The graphs and tables provided following this note are a statistical summary based on a limited number of
samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.
Note: Unless otherwise indicated, VIN = 3.6V, TA = 25°C, CIN = COUT = 10 µF, CFLY = 1 µF, all capacitors X7R ceramic.
5.05
5.04
5.03
10 mA
5.02
5.01
80 mA
5.00
4.99
2.0 2.5 3.0
120 mA
3.5 4.0
MCP1252-33X50
SELECT = GND
VOUT = 5.0V
4.5 5.0 5.5 6.0
Supply Voltage (V)
FIGURE 2-1:
Output Voltage vs. Supply
Voltage (MCP1252-33X50).
.
3.34
3.33 80 mA
120 mA
3.32
3.31
MCP1252-33X50
SELECT = VIN
VOUT = 3.3V
10 mA
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
Supply Voltage (V)
6.0
FIGURE 2-2:
Output Voltage vs. Supply
Voltage (MCP1252-33X50).
100
90
80
70 10 mA 80 mA
60 120 mA
50
40
30 MCP1252-33X50
20 SELECT = GND
10 VOUT = 5.0V
0
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Supply Voltage (V)
FIGURE 2-4:
Percent Efficiency vs.
Supply Voltage (MCP1252-33X50).
100
90
80 10 mA
70 80 mA
60 120 mA
50
40
30 MCP1252-33X50
20 SELECT = VIN
10 VOUT = 3.3V
0
2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Supply Voltage (V)
FIGURE 2-5:
Power Efficiency vs. Supply
Voltage (MCP1252-33X50).
3.02
3.01
10 mA
3.00
80 mA
2.99
120 mA
MCP1252-ADJ
VOUT = 3.0V
1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Supply Voltage (V)
FIGURE 2-3:
Output Voltage vs. Supply
Voltage (MCP1252-ADJ).
100
90
80
10 mA
70
60 80 mA
50 120 mA
40
30
20 MCP1252-ADJ
10 VOUT = 3.0V
0
1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Supply Voltage (V)
FIGURE 2-6:
Power Efficiency vs. Supply
Voltage (MCP1252-ADJ).
2002-2014 Microchip Technology Inc.
DS20001752C-page 5
5 Page 
5.1 Capacitor Selection
The style and value of capacitors used with the
MCP1252 and MCP1253 family of devices determine
several important parameters such as output voltage
ripple and charge pump strength. To minimize noise
and ripple, it is recommended that low ESR (0.1 )
capacitors be used for both CIN and COUT. These
capacitors should be either ceramic or tantalum and
should be 10 µF or higher. Aluminum capacitors are not
recommended because of their high ESR.
If the source impedance to VIN is very low, up to several
megahertz, CIN may not be required. Alternatively, a
somewhat smaller value of CIN may be substituted for
the recommended 10 µF, but will not be as effective in
preventing ripple on the VIN pin.
The value of COUT controls the amount of output volt-
age ripple present on VOUT. Increasing the size of
COUT will reduce output ripple at the expense of a
slower turn-on time from shutdown and a higher in-rush
current.
The flying capacitor (CFLY) controls the strength of the
charge pump. In order to achieve the maximum rated
output current (120 mA), it is necessary to have at least
1 µF of capacitance for the flying capacitor. A smaller
flying capacitor delivers less charge per clock cycle to
the output capacitor, resulting in lower output ripple.
The output ripple is reduced at the expense of maxi-
mum output current and efficiency.
5.2 Output Voltage Setting
The MCP1252-33X50 and MCP1253-33X50 feedback
controllers select between an internally-set, regulated
output voltage (3.3V or 5.0V). Connect SELECT to
GND for a regulated 5.0V output and connect SELECT
to VIN for a regulated 3.3V output.
The MCP1252-ADJ and MCP1253-ADJ utilize an
external resistor divider that allows the output voltage
to be adjusted between 1.5V and 5.5V. For an adjust-
able output, connect a resistor between VOUT and FB
(R1) and another resistor between FB and GND (R2). In
the following equation, choose R2 to be less than or
equal to 30 k and calculate R1 from the following
formula:
EQUATION 5-1:
R1 = R2VOUT VFB – 1
and:
EQUATION 5-2:
VOUT = VFB1 + R1 R2
where:
VOUT is the desired output voltage from 1.5V to 5.5V
VFB is the internal regulation voltage, nominally 1.21V
2002-2014 Microchip Technology Inc.
MCP1252/3
Note that the tolerance of the external resistors will
have an effect on the accuracy of the output voltage.
For optimum results, it is recommended that the
external resistors have a tolerance no larger than 1%.
5.3 Recommended Layout
The MCP1252 and MCP1253 family of devices transfer
charge at high switching frequencies, producing fast,
high peak, transient currents. As a result, any stray
inductance in the component layout will produce
unwanted noise in the system. Proper board layout
techniques are required to ensure optimum perfor-
mance. Figure 5-3 depicts the recommended board
layout. The input capacitor connected between VIN and
GND, and the output capacitor connected between
VOUT and GND, are 10 µF ceramic, X7R dielectric, in
1206 packages. The flying capacitor connected
between C+ and C- is a 1 µF ceramic, X7R dielectric in
a 0805 package. The layout is scaled 3:1.
VOUT
GND
VIN
PGOOD
SELECT
SHDN
C+
C-
FIGURE 5-3:
Recommended Printed
Circuit Board Layout.
DS20001752C-page 11
11 Page | ||
| Páginas | Total 20 Páginas | |
| PDF Descargar | [ Datasheet MCP1253.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| MCP1252 | (MCP1252 / MCP1253) Low Noise / Positive-Regulated Charge Pump | Microchip Technology |
| MCP1253 | (MCP1252 / MCP1253) Low Noise / Positive-Regulated Charge Pump | Microchip Technology |
| MCP1256 | Low-Ripple Charge Pump | Microchip Technology |
| MCP1257 | Low-Ripple Charge Pump | Microchip Technology |
| 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 |