LT1949-1EMS8#TRPBF Linear Technology, LT1949-1EMS8#TRPBF Datasheet - Page 4

• Manufacturer Part Number: LT1949-1EMS8#TRPBF
• Description: IC DC/DC CONV PWM 1A SWTCH 8MSOP
• Manufacturer: Linear Technology
• Type: Step-Up (Boost)r

Specifications of LT1949-1EMS8#TRPBF

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: Adj to 28V
• Current - Output: 1A
• Frequency - Switching: 1.1MHz
• Voltage - Input: 1.7 ~ 12 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -

V
nect a series RC network from this pin to ground. Typical
values for compensation are a 30k/330pF combination
when using ceramic output capacitors. Minimize trace
area at V
FB (Pin 2): Feedback Pin. Reference voltage is 1.24V.
Connect resistor divider tap here. Minimize trace area at
FB. Set V
SHDN (Pin 3): Shutdown. Pull this pin low for shutdown
mode (only the low-battery detector remains active).
Leave this pin floating or tie to a voltage between 1.4V and
6V to enable the device. SHDN pin is logic level and need
only meet the logic specification (1.4V for high, 0.4V for
low).
LT1949-1
TYPICAL PERFOR A CE CHARACTERISTICS
PI FU CTIO S
4
C
U
(Pin 1): Compensation Pin for Error Amplifier. Con-
C
OUT
.
U
according to: V
U
W
OUT
U
= 1.24V(1 + R1/R2).
AC COUPLED
100mV/DIV
500mA/DIV
V
OUT
I
L
Transient Response
V
V
40mA TO 140mA LOAD STEP
CIRCUIT FIGURE 1
IN
OUT
= 3.3V
= 10V
20 s/DIV
GND (Pin 4): Ground. Connect directly to local ground
plane.
SW (Pin 5): Switch Pin. Connect inductor/diode here.
Minimize trace area at this pin to keep EMI down.
V
pin.
LBI (Pin 7): Low-Battery Detector Input. 200mV refer-
ence. Voltage on LBI must stay between ground and
700mV. Low-battery detector remains active in shutdown
mode.
LBO (Pin 8): Low-Battery Detector Output. Open collec-
tor, can sink 10 A. A 1M pull-up is recommended.
IN
(Pin 6): Supply Pin. Must be bypassed close to the
1949-1 G10