ILC6390 Datasheet, PDF (1/9 Pages) Impala Linear Corporation – SOT-89 STEP-UP PFM SWITCHER WITH AUTO-LOAD SENSE

Impala Linear Corporation
ILC6390/91
SOT-89 Step-Up PFM Switcher
with Auto-Load Sense
General Description
50 mA boost converter using Pulse Frequency Modulation,
or PFM, technique, in 5-lead SOT-89 or a 5-lead SOT-23
package. Only 3 external components are needed to com-
plete the switcher design.
The ILC6390 automatically senses load variations to choose
between 55% and 75% duty cycles. Normal operation is 55%
duty at 155kHz; when load currents exceed the internal com-
parator trip point, a “turbo mode” kicks in to provide extend-
ed on-time switching (75% duty at 100kHz oscillation).
Requiring only 30µA of supply current, the ILC6390
achieves efficiencies as high as 85% at 5V yet shuts down
to 0.5µA max.
Standard voltages offered are 2.5, 3.3, and 5.0V and is
available in both a 5 lead SOT-23 and 5 lead SOT-89 pack-
age for small footprint applications.
In addition, the ILC6391 is configured to drive an external
transistor to achieve higher power levels.
Features
• 85% conversion efficiency at 50mA out
• Start-up voltages as low as 900mV
• ±2.5% accurate outputs
• Complete switch design with only 3 external components
• Automatically senses load variations to select the optimal
duty cycle and extend conversion efficiencyover a wide
range
• External transistor configuration to run as switcher
controller
• Shutdown to 0.5µA
Applications
• Cellular phones, pagers
• Cameras, video recorders
• Palmtops and PDAs
Block Diagram
L_X
V_SS
EXT
V_LX LIMITER
BUFFER
2-STEP PFM
CONTROLLED OSC
100/155kHz
V_DD
V_REF
+
-
V_OUT
Ordering Information
CE
CHIP ENABLE
+
- ^4~5mV
Pin-Package Configurations
L_X
V_SS
5
4
SOT-25
(TOP VIEW)
1
2
3
CE
V_DD
N/C
ILC6390CM
V_SS
L_X
5
4
SOT-89-5
(TOP VIEW)
L_X
V_SS
5
4
SOT-25
(TOP VIEW)
1
2
3
CE
V_DD
N/C
ILC6391CM
V_SS
L_X
5
4
SOT-89-5
(TOP VIEW)
ILC6390CM-25
ILC6390CM-33
ILC6390CM-50
ILC6391CM-25
ILC6391CM-33
ILC6391CM-50
ILC6390CP-25
ILC6390CP-33
ILC6390CP-50
ILC6391CP-25
ILC6391CP-33
ILC6391CP-50
2.5V ± 2.5%
3.3V ± 2.5%
5.0V ± 2.5%
3.3V ± 2.5% driving external transistor
3.3V ± 2.5% driving external transistor
5.0V ± 2.5% driving external transistor
2.5V ± 2.5%
3.3V ± 2.5%
5.0V ± 2.5%
3.3V ± 2.5% driving external transistor
3.3V ± 2.5% driving external transistor
5.0V ± 2.5% driving external transistor
* Standard product offering comes in tape & reel, quantity 3000 per
reel, orientation right for SOT-25, quantity 1000 per reel orientation
right for SOT-89.
1
2
3
N/C
V_OUT
CE
ILC6390CP
1
2
3
N/C
V_OUT
CE
ILC6391CP
Impala Linear Corporation
ILC6390 1.1
[phone] www.impalalinear.com
Feb 2001 1