LT1310 Datasheet, PDF (1/12 Pages) Linear Technology – 1.5A Boost DC/DC Converter with Phase-Locked Loop

LT1310
1.5A Boost
DC/DC Converter
with Phase-Locked Loop
FEATURES
s _{Synchronizable or Constant Frequency}
Low Noise Output
s _{Synchronizable Up to 4.5MHz}
s _{Wide Input Voltage Range: 2.8V to 18V}
s _{Low Profile Surface Mount Solution}
(All Ceramic Capacitors)
s _{Low VCESAT Switch: 240mV at 1A}
s _{Adjustable Output from VIN to 35V}
s _{Small Thermally Enhanced 10-Lead MSOP Package}
U
APPLICATIO S
s _Instruments
s _Avionics
s _{Data Acquisition}
s _{Communications}
s _Imaging
s _Ultrasound
DESCRIPTIO
The LT^®1310 boost DC/DC converter combines a 1.5A
current mode PWM switcher with an integrated phase-
locked loop, allowing the user to set the switching fre-
quency anywhere from 10kHz to 4.5MHz. Intended for use
in applications where switching frequency must be accu-
rately controlled, the LT1310 can generate 12V at up to
400mA from a 5V input.
Switching frequency is set with an external capacitor, and
the device can be operated in either free-running or phase-
locked mode. A wide capture range of nearly 2:1 allows the
free-running frequency to be set using standard ±10%
tolerance NP0 dielectric capacitors.
The LT1310 is available in the tiny thermally enhanced
10-lead MSOP package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
V_IN
5V
SHUTDOWN
SYNC
1.6MHz
L1
5.6µH
D1
C1
4.7µF
CERAMIC
3.01k
1500pF
LT1310
V_IN
SHDN
SW
FB
SYNC
PLL-LPF
V_C
C_T
GND*
15k
820pF
100pF
NP0
C1: 4.7µF, X5R OR X7R, 6.3V
C2: 4.7µF, X5R OR X7R, 16V
D1: MICROSEMI UPS120 OR EQUIVALENT
L1: PANASONIC ELL6SH-5R6M
*EXPOSED PAD MUST ALSO BE GROUNDED
V_OUT
12V
400mA
178k
20.5k
C2
4.7µF
CERAMIC
1310 F01a
Figure 1. 5V to 12V Converter Synchronized at 1.6MHz
LT1310 Efficiency
90
V_OUT = 12V
85
5V_IN
80
3.3V_IN
75
70
65
60
55
50
45
40
35
0
100
200
300
400
LOAD CURRENT (mA)
1310 F01b
1310f
1