AN-1030 Datasheet, PDF (1/6 Pages) Cymbet Corporation – EVAL-08 Frequently Asked Questions & Troubleshooting

Preliminary
AN-1030
Application Note
EVAL-08 Frequently Asked Questions & Troubleshooting Guide
Features
The CBC-EVAL-08 is a demonstration kit combining a
solar panel energy transducer with the EnerChip EH
CBC5300 Energy Harvesting module that has two
50 µAh EnerChip Batteries. The EnerChips provide
storage and starting power for the energy harvesting
module. The purpose of this demonstration platform
is to enable designers to quickly develop Energy
Harvesting applications. A block diagram of the
EVAL-08 is shown in Figure 1.
Photovoltaic
Cell
Control
Lines _Vout
Connector
Boost
Converter
Power
Management
Charge
Control
2 - EnerChip
CBC050
Figure 1: EnerChip EVAL-08 Demo Kit Block Diagram
System Description
The photovoltaic cells convert ambient light energy
into electrical energy. The output voltage of the
photovoltaic cells is too low to charge the EnerChips
and power the rest of the system directly, so a
boost converter is used to boost the photovoltaic
cell voltage to the voltage needed to charge the
EnerChips.
The charge control block continuously monitors
the output of the boost converter. If the output of
the boost converter falls below the voltage needed
to charge the EnerChips, the charge controller will
disconnect the boost converter from the EnerChips.
This prevents the EnerChips from back powering the
boost converter in low ambient light conditions.
Figure 2: CBC-EVAL-08 EVAL Kit - 3.55 x 2 in.
The power management block is used to protect
the EnerChips from discharging too deeply in low
ambient light conditions, or abnormally high current
load conditions. The power management block
also ensures that the load is powered up with a
smooth power on transition. The power management
block has a control line (CHARGE) for indication to
the system controller that the energy harvester is
charging the EnerChips. A control line input (BATOFF)
is available for the controller to disconnect itself
from the EnerChips when it is desired to conserve
battery life for as long as possible in prolonged low
ambient light conditions.
The EVAL-08 shown in Figure 2 with the EnerChip EH
Module mounted on the Solar board with 100 µAh
capacity.
There are two connectors on the EVAL-08 for
connection to target devices to be powered. Either
connector can be used for low power microcontroller
based systems. In the case of a low-power wireless
end device, the EVAL-08 has storage energy for up to
1000 transmissions - depending on protocol used -
in no/low ambient light conditions.
Microcontroller systems that are powered by the
EVAL-08 should contain firmware that is “Energy
Harvesting Aware” and take advantage of the power
management status and control signals in the CBC-
EVAL-08.
©2008 Cymbet Corporation • Tel: [phone] • www.cymbet.com
Doc AN-72-1030 Rev02
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