ml4854 Fairchild Semiconductor, ml4854 Datasheet - Page 2

• Manufacturer Part Number: ml4854
• Description: Adjustable, Low-current, 2-cell Boost Regulator With Shutdown And Low Battery Detect
• Manufacturer: Fairchild Semiconductor

PRODUCT SPECIFICATION
Pin Configuration
Pin Description
Absolute Maximum Ratings
Absolute maximum ratings are those values, beyond which the device could be permanently damaged. Absolute maximum
ratings are stress ratings only and functional device operation is not implied.
2
Parameter
V
Switch Voltage (V
Voltage on any other Pin
Peak Switch Current (Ipeak)
Output Current (I
Continuous Power Dissipation
Thermal Resistance ( θ
Junction Temperature
Storage Temperature Range
Lead Temperature (soldering, 10s)
PIN
1
2
3
4
5
6
7
8
IN
,
V
OUT
NAME
SHDN
V
GND
LBO
LBI
FB
V
OUT
V
IN
L
Voltages (Relative to GND)
Battery Input Voltage . Supplies the IC during start-up. After the output is running, the IC draws
power from V
Shut Down . Pulling this pin low shuts down the regulator, isolating the load from the input.
Low-Battery Input . Pulling this pin below a threshold causes the LBO pin to go low.
Low-Battery Output . This pin provides an active low signal to alert the user when the LBI
voltage falls below its targeted value. The open-drain output can be used to reset a
microcontroller.
Programming Feedback Pin . Sets the output voltage. This pin is used to adjust the output
voltage via a resistive divider from V
Boost regulator output . Output voltage can be set to be in the 3 to 5V range. Startup at
moderate load is achievable at input voltages around 1.25V.
Boost inductor connection . An inductor is connected between this pin and V
the output supply, this pin pulls low, charging the inductor, then shuts off dumping the energy
through the synchronous rectifier to the output.
Ground of the IC .
OUT
L
to GND)
)
JA
)
OUT
.
SHDN
LB0
LBI
V
IN
8-Lead TSSOP (T08)
1
2
3
4
TOP VIEW
OUT
.
FUNCTION
8
7
6
5
GND
V
V
FB
L
OUT
Min.
-0.3
-0.3
-0.3
-65
— Internally Limited —
V
V
OUT
OUT
Max.
+165
500
320
124
150
300
7
+0.3
+0.3
IN
. When servicing
REV. 1.0.7 5/6/03
Units
°C/W
mW
mA
°C
°C
°C
V
V
V
ML4854