Pololu Orangutan LV-xx8 - Manual (Page 8)

Orangutan LV-168 Power & Motor Connections
Just like the Orangutan SV-xx8, the power and motor connections are on the right side of the unit. The Orangutan
LV-168 is designed to operate off of three NiMH cells, which corresponds to a voltage range of about 2.5 –
4.5 V. However, the unit can operate from two or four NiMH cells with some limitations. At lower voltages, the
effectiveness of the motor drivers (H-bridges) is reduced, and the 5 V step-up regulator’s available output current
decreases. Beyond 5 V, the step-up regulator ceases operation and the input voltage shows up on the Vcc line; the
components on the board can operate to 5.5 V, but some sensors you use might have a 5.25 V limit.
The Orangutan LV-168’s motor drivers can briefly deliver up to 5 A each, but each motor driver is protected by a 2 A
resettable fuse that is triggered by excessive temperature. If the motors draw much more than 2 A for more than a
few seconds, the voltage to the motors will be reduced, but normal operation will resume once the board has cooled
down. In its factory configuration, an on-board temperature sensor is connected through a jumper to ADC6 for some
(limited) feedback about the board temperature.
User I/O & Power Outputs
The eight user I/O lines can be accessed via the 8×3 0.100" female header along the upper edge of the board, as shown
below. Each line has associated power and ground connections for easy connections to sensors: the exterior (top) pin
is ground, the middle pin is power, and the interior(bottom) pin is signal and connects directly to an AVR I/O line.
Orangutan SV-xx8 and LV-168 user I/O header.
The power row is divided into two banks of four pins, and each bank can either connect directly to the battery voltage
or to the 5 V generated on the board; this connection is determined by the bank’s associated power selection jumper.
On the Orangutan LV-168, the total current available to the 5 V line is approximately 150 mA, but the exact amount
depends on your input voltage. On the Orangutan SV-xx8, the total current available to the 5 V line is 3 A, meaning
you can power servos and other high-power peripherals directly from your regulated voltage. Please note that you
should use something more robust than the supplied power-selection shorting blocks if you plan on pulling much
more than an amp from a single bank.
From left to right, the signal connections along the bottom row are: PC5, PC4, PC3, PC2, PC1, PC0, PD1, and PD0.
Pins PC0 – PC5 can be used as either digital I/Os or analog inputs. Pins PD0 and PD1 are digital I/Os that connect to
the ATmega168’s UART hardware, which means you can use them as logic-level (TTL) serial receive and transmit
lines, respectively. Two additional dedicated analog inputs (ADC6 and ADC7) are connected by default to hardware
on the board, but their jumpers can be removed to provide user access to these inputs. ADC7 is connected to the
user trimmer potentiometer by the shorting block next to the reset button; the left pin of the shorting block header
is tied directly to ADC7. ADC6 is connected to the LV-168’s temperature sensor and the SV-xx8’s battery voltage
monitoring circuit via a surface-mount jumper on the bottom side of the PCB. You can use a soldering iron to break
this short, and you can make your own connection to ADC6 using the right of the two shorting pads.
Pololu Orangutan SV-xx8 and LV-xx8 User's Guide © 2001–2014 Pololu Corporation
4. Module Pinouts, Component Identification, and Usage Notes Page 8 of 18