ILC6383 Datasheet, PDF (1/15 Pages) Fairchild Semiconductor – 1-Cell to 3-Cell Boost DC-DC Converter with True Load Disconnect, 3.3V, 5V or Adjustable Output

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ILC6383
1-Cell to 3-Cell Boost DC-DC Converter with True
Load Disconnect, 3.3V, 5V or Adjustable Output
Features
• Guaranteed start up in PWM at 0.9V input
• Synchronous rectification requires no external diode
• True load disconnect from battery input in shutdown
• Up to 75mA at 3.3V and 40mA at 5V from 1V input
• Up to 375mA at 3.3V and 300mA at 5V from 3V input
• Peak efficiency > 90%
• 1µA battery input current in shutdown (with V_OUT = 0V)
• Internal Oscillator frequency: 300kHz to ±15%
• ILC6383: Fixed 3.3V or 5V output
• ILC6383-ADJ: Adjustable output to 6V maximum
• Low battery detector with 100ms transient rejection delay
• Powergood output flag when V_OUT is in regulation
Applications
• Cellular Phones, Pagers
• Palmtops, PDAs and portable electronics
• High efficiency 1V step up converters
Description
The ILC6383 series of step-up DC-DC converters operate
from 1-cell to 3-cell input. They are direct replacement for
ILC6382, in applications where SYNC pin is not used. The
PFM or PWM operating mode is user selectable through
SEL pin connected to ground or left open, respectively. The
choice should be dependent upon the current to be delivered
to the load: PFM is recommended for input voltage higher
than 1.5V and loads below 100mA, while PWM is recom-
mended for more than 50mA load current and in noise sensi-
tive applications. In shutdown mode, the device allows true
load disconnect from battery input. Designed for wireless
communications applications, the oscillator frequency is set
at 300kHz with no harmonics at sub 20kHz audio band or at
455kHz IF band.
Internal synchronous rectification and externally selectable
PFM/PWM mode of operation allows the selection of the
best efficiency at light or full load. The ILC6383 is capable
of delivering 75mA at 3.3V output from a single cell input.
The ILC6383-XX offers 3.3V or 5V fixed output voltage
while the ILC6383-ADJ allows adjustable output voltage to
6V maximum. Output voltage accuracy is ±3.5% over full
operating temperature range.
Additional features include power good output (POK) and an
internal low battery detector with 100ms transient rejection
delay. The device will reject low battery input transients
under 100ms in duration. The ILC6383 series is available in
a space saving eight lead micro SOP (MSOP-8) package.
Typical Applications
CIN
47µF
L
+
VIN
1 to 3-cell
ON
OFF
15µH
R5
R6
ILC6383-XX
1
LX VOUT 8
2 VIN
GND 7
3 LBI/SD ^LBO 6
4 SEL ^POK 5
PWM
PFM
MSOP-8
+ 47µF ^VOUT
COUT
Low Battery
Detector Output
Power Good Output
Figure 1. ILC6383CIR-XX
CIN
47µF
L
+
VIN
1 to 3-cell
ON
OFF
15µH
R5
R6
ILC6383-ADJ
1
LX ^{VOUT 8}
2 VIN
GND 7
3 _LBI/SD LBO 6
4 SEL
VFB 5
PWM
PFM
MSOP-8
+ COUT
47µF
VOUT
R1
R2
VOUT = 1.25 (1+R1/R2)
Figure 2. ILC6383CIR-ADJ
REV. 1.2.6 6/13/02