Linear Technology DC1764A Demo Manual

DESCRIPTION
Demonstration circuit 1764A is a 5.5V input, 12V output
at 800mA DC/DC power supply featuring the LTC
The IC includes internal high and low side 2.5A switches
and features selectable PWM or Burst Mode
for high efficiency at low output current. The board oper-
ates from an input voltage as low as 1.8V and continues
to operate down to 500mV once started. The output is
fixed at 12V although other voltages between 2.2V and
15V can be selected by resistor changes.
The IC includes soft-start and input current limit, adjust-
able switching frequency with the ability to synchronize
to an external clock, and output overvoltage protection
with output disconnect.
PERFORMANCE SUMMARY
PARAMETER
Input Voltage Range
Output Voltage
Output Current
Output Voltage Ripple (PWM Mode)
Output Voltage Ripple (Burst Mode Operation)
Switching Frequency
DEMO MANUAL DC1764A
High Efficiency 15V 2.5A
Synchronous Step-Up Converter
Included on the board are jumpers for ON/OFF and oper-
®
3122. ating MODE, PWM or BURST. Terminals are included for
connecting V
® operation
The LTC3122 data sheet gives a complete description of the
IC operation and application information. The data sheet
must be read in conjunction with this quick start guide.
Design files for this circuit board are available at
http://www.linear.com/demo
L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks
of Linear Technology Corporation. All other trademarks are the property of their respective
owners.
Specifications are at T = 25°C
A
CONDITION
V = 5V, V Load = 800mA
IN OUT
V = 5V, V = 12V
IN OUT
V = 5V, V = 12V, V Load = 500mA
IN OUT OUT
V = 5V, V = 12V, V Load = 50mA
IN OUT OUT
LTC3122EDE
and V as well as ON/OFF and SYNC.
IN OUT
VALUE
1.8V to 5.5V
12V ±3%
800mA
40mV
200mV
1MHz ±15%
P-P
P-P
dc1764af
1