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CONFIGURATION SETTINGS
Demonstration circuit SCP-LTC3114-1-EVALZ features the
LTC3114-1, a wide operating range, synchronous mono-
lithic buck-boost converter with programmable average
output current. The circuit operates with a 2.2V to 40V in-
put voltage range.
The output of the SCP-LTC3114-1-EVALZ is resistor-pro-
grammable from 3.0V to 40V. The board can be also con-
figured to drive VIOC-capable linear regulators.
OUTPUT VOLTAGE PROGRAMMING
R1
⎛
⎞
= 1 .0 V 1 +
V
⎝ ⎜
⎠ ⎟
OUT
R2
Table 2. Resistor Selection Guide for Common Output Voltages
V
(V)
OUT
3.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
12.0
13.0
14.0
15.0
16.0
17.0
18.0
19.0
20.0
21.0
22.0
23.0
24.0
25.0 (Note 1)
30.0 (Note 1)
35.0 (Note 1)
40.0 (Note 1)
Note 1. Output capacitor rating limited. Replace for higher V
DEMO MANUAL SCP-LTC3114-1-EVALZ
R
(Ω)
R
(Ω)
1
2
2M
1M
2M
499k
2M
402k
2M
332k
2M
287k
2M
249k
2M
221k
2M
200k
2M
182k
2M
165k
2M
154k
2M
143k
2M
133k
2M
124k
2M
118k
2M
110k
2M
105k
2M
100k
2M
95.3k
2M
90.9k
2M
86.6k
2M
82.5k
2M
69.8k
2M
59k
2M
51.1k
OUT.
RUN PIN CONFIGURATION
The RUN pin is tied to the optional SCP Run/Sequence
header P1. To create a harness for this function, use Molex
part 0510650300 with crimp pin 50212-8000.
To use an active run signal, use a 1.00MW for either pull-
up or pull-down resistors R5 and R6, short R9 with 0W,
and use the drive signal from connector P1.
VOLTAGE INPUT-TO-OUTPUT CONTROL (VIOC)
IMPLEMENTATION
To implement the VIOC function for this regulator, set R
to 0W. Refer to the "Configuration Settings" section in the
Demo Manual for the low-dropout (LDO) linear regulator
board and use the following configuration for this board.
Table 3. VIOC Cross-Reference Designators
VIOC SETTING REFERENCES
V
Reference Designators
OUT
-
=
=
V
V
V
1.0V
LDOIN
LDOOUT
VIOC
æ
+
R
R
=
BOT
TOP
ç
(
)
V
1.0V
MAX LDOIN
è
R
BOT
I
is the current through R
SINK
should be sized such that the divider current runs a mini-
mum of 100µA to minimize the I
R
R
R
BOT
TOP
MAX
R2
R1
R8
æ
ö
R
+
R
BOT
TOP
ç
÷
R
è
ø
BOT
ö
+
R
MAX
+
÷
I
R
SINK MAX
ø
, typically 15µA, so R
MAX
error term.
SINK
12
BOT
Rev. 0
3
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