DC1449A - Demo Manual

DEMO C IR C U IT 1 4 4 9
Q U IC K S TA R T G U IDE
U ltra lo w P o w e r B o o s t C o n v e rte r w ith Du a l H a lf-B rid g e S w itc h e s
DESCRIPTION
Demonstration circuit 1449A is an Ultralow Pow er Boost
Converter w ith Dual Half-Bridge Sw itches featuring the
LT8415. It converts a 3V-10V source to 16V supplying
1.6mA at 3Vin and 10mA at 10Vin. The 16V output is
used to bias the DualHalf-Bridges w hich are activated by
IN1 and IN2 and are pinned out at VOUT1 and VOUT2.
IN1 controls VOUT1 w ith the same polarity and IN2 controls VOUT2. Each Half-Bridge drives a 200pF on-board
capacitor.
The LT8415 features a low noise control scheme, integrated pow er sw itch, dualhalf-bridge sw itches, schottky
diode and output disconnect function, ultra-low quiescent current, built in soft-start and overvoltage protection. The LT8415 datasheet gives a complete description
of the part, its operation and application information. The
datasheet must be read in conjunction w ith this quick
start guide for w orking on or modifying the demo circuit
1449.
This circuit is intended for space-conscious applications
such as Sensor Pow er, RF M ems, Low Pow er Actuator
Bias/Control, Liquid Lens Drivers and General Purpose
Bias Supplies.
Design files for this circuit board are available. Call
the LTC factory.
L, LTC, LTM , LT are registered trademarks ofLinear Technology Corporation.
PERF ORM ANCE SU M M ARY F OR DC1 3 8 7 A-A/L T8 4 1 0
SYM BOL
VIN
VOUT
VOUT
RIPPLE
EFFICIENCY
EFFICIENCY
PARAM ETER
Input Supply Range
Output Voltage Range
Output Voltage Range
CONDITIONS
VIN = 3V, ILOAD = 1.6mA
VIN = 10V, ILOAD = 10mA
VIN = 10V, ILOAD = 10mA
VIN = 3V, ILOAD = 1.6mA
VIN = 10V, ILOAD = 10mA
Specifications are at TA = 25°C
M IN
3
15.54
15.54
TYP
16
16
20
73
83
M AX
10
16.48
16.48
UNITS
V
V
V
mV
%
%
1
Q U ICK START PROCEDU RE
Demonstration circuit 1449 is easy to set up to evaluate
the performance of the LT8415. Refer to Figure 1 for
proper measurement equipment setup and follow the
procedure below :
1. Place jumpers in the follow ing positions:
JP1 Run
2. W ith pow er off, connect the input pow er supply to
Vin and G N D.
3. Turn on the pow er at the input.
Check for the proper output voltages. Vout = 15.52V to 16.48V.
NOTE. Ifthere is no output, temporarily disconnect the load to make sure
that the load is not set too high.
4. O nce the proper output voltage is established, adjust the load w ithin the operating range and observe the output voltage regulation, ripple voltage,
efficiency and other parameters.
5. To test the VO U T1 and VO U T2 outputs, apply a
logic levelsquare w ave signal(typically 0V to 2V) at
IN 1 and/or IN 2 and observe the amplitude levels
and associated delays at VO U T1 and VO U T2. See
datasheet for response driving externalcapacitors.
Figure 1. Proper M easurem ent Equipm ent Setup
2
3