Linear Technology DC1793A Demo Manual

DESCRIPTION
Demonstration circuit 1793A is a high voltage inverting
charge pump with low noise dual-polarity LDO regula-
tors featuring the LTC ® 3260EMSE. The LTC3260 operates
with an input voltage from 4.5V to 32V. The demo board
provides selectable LDO± output set magnitudes of
3.3V, 5V, 12V and 24V for each polarity. Additional LDO±
set point jumper selections and optional topside ADJ±
resistors allow the user to set other desired LDO± output
voltages. The demo board also provides the means to select
between Burst Mode ® operation or constant-frequency
PERFORMANCE SUMMARY
SYMBOL PARAMETER
V Input Voltage
IN
VLDO+ LDO+ Output Voltage
VLDO– LDO– Output Voltage
V Output Voltage
OUT
QUICK START PROCEDURE
Refer to Figure 1 for the proper measurement equipment
setup and jumper settings, and follow the procedure
below.
NOTE: When measuring the input or output voltage ripple,
care must be taken to avoid a long ground lead on the
oscilloscope probe. Measure the input or output voltage
ripple by touching the probe tip directly across the V
V and GND terminals. See Figure 2 for proper scope
OUT
probe technique.
DEMO MANUAL DC1793A
High Voltage, Low Noise, Dual Supply
mode operation, plus select an operating frequency of
500kHz, 200kHz, and 50kHz.
The LTC3260 data sheet gives a complete description of
the device, operation and application information. The
data sheet must be read in conjunction with this quick
start guide for demo circuit 1793A.
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
CONDITIONS
V ≥ LDO+ Set Point + 0.8V
IN
V ≤ LDO– Set Point – 0.5V
OUT
MODE = 0V
MODE ≥ 2V
1. Make sure the jumper settings are as follows:
or
IN
2. Set PS1 to 12V.
LTC3260EMSE
Inverting Charge Pump
= 25°C
A
MIN TYP
4.5
1.2
–32
–V
–0.94 • V
JP1: EN+ is in the ON position.
JP2: EN– is in the ON position.
JP3: MODE is in the BURST position.
JP4: FREQ is in the 500kHz position.
JP5: LDO+ is set to the 5V setting.
JP6: LDO– is set to the –5V setting.
MAX UNITS
32
32
–1.2
IN
IN
dc1793afa
1
V
V
V
V
V