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Integral |
IZ1583
General Description
The IZ1583 is a step-down regulator with a built in internal power MOSFET. The IC provide 3A
continuous output current over a wide supply voltage range. The IC can be used as distributed
power source, battery charger, pre-regulator for linear regulators.
Features
• Wide supply voltage range 4,75 … 23 V.
• Wide operating temperature range -40 … +85 oC.
• Active mode consumption current (max.) 1,2 mA .
• Chip dimensions 1,91 × 1,42 mm.
• ICs are available for shipment in chip form on unsawn wafers
• Functionality
IC performs driving of power built in MOSFET switch, quantity of energy transferred to load is
regulated by means of MOSFET on-time (pulse-width modulation). So ouput voltage practically do
not depends from load.
Table 1 – Contact pad description
Pad number Symbol
Description
01 BS n-channel power output MOSFET switch drive input
02 V
CC IC supply pin. Connected to 6,5V … 32 V power source. Bypass Vcc
to GND with a suitably large capacitor to eliminate noise on the input
to the IC.
03 SW Power switch output. SW has to be connected by output LC filter to
the output load and by mentioned capacitor to BS.
04 GND Common pin (ground)
05 FB
Feedback Input, has to be connected by a resistive voltage divider to
output voltage
06 COMP Frequency compensation Node has to be connected by series RC net-
work to GND
07 EN Digital enable/disable input. High level applied to EN turns IC ON
and low level – turns it OFF. For automatic startup, leave EN uncon-
nected.
08 SS Soft Start. SS is purposed to control the soft start period. To set soft
start mode connect SS & GND by capacitor. A 0.1µF capacitor sets
the soft-start period to 10ms. To disable the soft-start feature, leave SS
unconnected.
Ver.00/10.11.2008
1
http://www.Datasheet4U.com
V CC
Internal
Regulators
Oscilator
40/385 kHz
Shutdown
comparator
EN 0,7V
1uA
2,285/2,495V
Lockout
comparator
Current
limiter
5V
SQ
RQ
PWM-
comparator
100K
1,8 V
0,7V
Frequency
foldback comparator
1,22V
Error
amplifier
FB
COMP
SS
Fig. 1 – Electric block diagram
IZ1583
BS
M1
SW
M2
GND
Ver.00/10.11.2008
2
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