|
|
PDF ML1565 Data sheet ( Hoja de datos )
| Número de pieza | ML1565 | |
| Descripción | Step-Up-Down DC-DC Converts | |
| Fabricantes | Minilogic Device | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de ML1565 (archivo pdf) en la parte inferior de esta página. Total 21 Páginas | ||
|
No Preview Available !
ML1565
www.DataSheet4U.com
Step-Up-Down DC-DC Converts
Digital Still camera Power Supply
High-Efficiency, 5-channel
ML1565
General Description
The ML1565 provides a complete power-supply solution
for digital still and video cameras through the integration
of ultra-high-efficiency step-up/step-down DC-to-DC con-
verters along with three auxiliary step-up controllers. The
ML1565 is targeted for applications that use either 2 or 3
alkaline or NiMH batteries as well as those using a single
lithium-ion (Li+) battery.
The step-up DC-to-DC converter accepts inputs from 0.7V
to 5.5V and regulates a resistor-adjustable output from
2.7V to 5.5V. It uses internal MOSFETs to achieve
95% efficiency. Adjustable operating frequency facilitates
design for optimum size, cost, and efficiency.
The step-down DC-to-DC converter can produce output
voltages as low as 1.25V and also utilizes internal
MOSFETs to achieve 95% efficiency. An internal softstart
ramp minimizes surge current form the battery. The
converter can operate from the step-up output providing
buck-boost capability with up to 90% compound efficiency,
or it can run directly from the battery if buck-boost
operation is not needed. The ML1565 features auxiliary
step-up controllers that power CCD, LCD, motor actuator,
and backlight circuits. The ML1565 is available in a
space-saving QFN-32 thin package.
■ Pin Configuration
Features
Step-up DC-to-DC Converter:
95% Efficient
3.3V (Fixed) or 2.7V to 5.5V (Adjustable) Output
Voltage
Step-Down DC-to-DC Converter:
Operate form Battery for 95% Efficient Buck
Combine with Step-Up for 90% Efficient Buck-Boost
Adjustable Output Down to 1.25V
Three Auxiliary PWM Controllers
Up to 1MHz Operating Frequency
1µA Shutdown Mode
Internal Soft-Start control
Overload Protection
Compact 32-Pin, 5mmx5mm Thin QFN Package
Ordering Information
Item
ML1565QFNG
Package Mark
Shipping
QFN-32 ML1565 160pcs/ Tray
Applications
Digital Still Cameras
Digital video Cameras
PDAs
■ Typical operating Circuit
ML1565
ML1565
--
P1/21
Rev. C, Sep 2005
1 page  
ML1565
Electrical Characteristics (VOUTSU = 3.3V, TA = -40℃, to + 85℃ unless otherwise specified)
General
Parameter
Input Voltage Range
Minimum Startup Voltage
Shutdown Supply current into
OUTSU
Step-Up DC-to-DC Supply
Current into OUTSU
Step-Up Plus 1AUX Supply
Current into OUTSU
Step-Up Plus Step-Down Supply
Current into OUTSU
Reference Output Voltage
Reference Load Regulation
Reference Line Regulation
OSC Discharge Trip Level
OSC Discharge Resistance
Condition
(Note 2)
ILOAD < ImA, TA = +25℃ startup voltage tempco is
-2300ppm/℃ (typ) (Note 3)
ONSU=ONSD=ON1=ON2=ON3=0; OUTSU=3.6V
ONSU=3.35V, FBSU=1.5V
(does not include switching losses)
ONSU=ON_=3.35V, FBSU=1.5V, FB_=1.5V
(does not include switching losses)
ONSU=ONSD=3.35V, FBSU=1.5V, FBSD=1.5V
(does not include switching losses)
IREF = 20µA
10µA<IREF<200µA
2.7V<OUTSU<5.5V
Rising edge
OSC = 1.5V, IOSC = 3mA
Min Typ. Max Unit
0.7 5.5 V
1.1 V
5 µA
400 µA
600 µA
1.23
1.225
650
1.27
10
5
1.275
80
µA
V
mV
mV
V
Ω
Step-Down DC-DC Converter
Parameter
FBSD Regulation Voltage
OUTSD Regulation Voltage
FBSD to COMPSD
Transconductance
FBSD Input Leakage Current
Burst Mode Trip Level
LXSD Leakage Current
Switch On-Resistance
P-Channel Current Limit
SDOK Output Low Voltage
SDOK Operating Voltage Range
Condition
FBSELSD = GND
FBSD = COMPSD
FBSD = 1.25V
(Note 6)
VLXSD = 5.5V, OUTSU = 5.5V
VLXSD = 0V, OUTSU = 5.5V
N-channel
P-channel
FBSD = 0.4V; 0.1mA into SDOK pin
Min
1.225
1.47
80
-100
110
0.7
1.0
Typ.
Max
1.275
1.53
185
+100
195
20
20
150
250
1.0
0.1
5.5
Unit
V
V
µS
nA
mA
µA
µA
mΩ
mΩ
A
V
V
P5/21
Rev. C, Sep 2005
5 Page 
ML1565
Detailed Description (2)
● Buck-Boost Operation
The step-down input can be powered from the output of
the step-up. By cascading these two channels, the
step-down output can maintain regulation even as the
battery voltage falls below the step-down output voltage.
This is especially useful when trying to generate 3.3V
from 1-cell Li+ inputs, or 2.5V from 2-cell alkaline or NiMH
inputs, or when designing a power supply that must
operate from both Li+ and alkaline/NiMH inputs.
Compound efficiencies of up to 90% can be achieved
when the step-up and step-down are operated in series.
Note that the step-up output supplies both the step-up
load and the step-down input current when the step-down
is powered from the step-up. The step-down input current
reduces the available step up output current for other
loads.
Direct Battery Step-down Operation
The step-down converter can also be operated directly
from the battery as long as the voltage at INSD does not
exceed OUTSU by more than a Schottky diode forward
voltage. When using this connection, connect a Schottky
diode from the battery input to OUTSU to INSD, which
adds a small additional current drain (of approximately
(VOUTSU – VINSD) / 10kΩ from OUTSU when INSD is not
connected directly to OUTSU.
Step-down direct battery operation improves efficiency for
the step-down output (up to 95%), but limits the upper limit
of the output voltage to 200mV less than the minimum
battery voltage. In 1-cell Li+ designs (with a 2.7V min), the
output can be set up to 2.5V. In 2-cell alkaline or
NiMH designs, the output may be limited to 1.5V or 1.8V,
depending on the minimum allowed cell voltage.
The step-down can only be briefly operated in dropout since
the ML1565 fault protection detects the out-of-regulation
condition and activates after 100,000 OSC cycles, or 200ms
at 500kHz. At that point, all ML1565 channels shut down.
Auxiliary DC-to-DC Controllers
The three auxiliary controllers operate as fixed-frequency
voltage-mode PWM controllers. They do not have internal
MOSFETs, so output power is determined by external
components. The controllers regulate output voltage by
modulating the pulse width of the DL_ drive signal to an
external N-channel MOSFET switch.
Figure 3 shows a functional diagram of an AUX controller
channel. A sawtooth oscillator signal at OSC governs timing.
At the start of each cycle, DL_ goes high, turning on the
external N-FET switch. The switch then turns off when the
internally level-shifted sawtooth rises above COMP_ or when
the maximum duty cycle is exceeded. The switch remains off
until the start of the next cycle. A transconductance error
amplifier forms an integrator at COMP_ so that DC high-loop
gain and accuracy can be maintained.
The auxiliary controllers do not start until the step-up
DC-to-DC output is in regulation. If the step-up, step-down or
any of the auxiliary controllers remains faulted for 100,000
OSC cycles, the all ML1565 channels latch off.
P11/21
Rev. C, Sep 2005
11 Page | ||
| Páginas | Total 21 Páginas | |
| PDF Descargar | [ Datasheet ML1565.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| ML1565 | Step-Up-Down DC-DC Converts | Minilogic Device |
| 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 |