Cute-1.7 + APD

Laboratory for Space Systems

Cute-1.7 + APD Project - Sub Systems > EPS -

Small Satellite Project (SSP)

Laboratory for Space Systems (LSS), Tokyo Institute of Technology

Top Subsystems EPS

EPS Subsystem ?

Power Source
Energy Storage
Power Distribution
Power Regulation & Control

Configuration of EPS Circuit Board

Detect the voltage and current of Solar Cells
Detect the charge/discharge current of Battery
Control Solar Cell Output and charge voltage of battery
Shut down over current
6.0V Step Up DC-DC Converter
5.0V Step Up-Down DC-DC Converter
3.3V Step Down DC-DC Converter
Load Switch

EPS Circuit Diagram (click to enlarge)

Solar Cell

High Efficiency of GaAs Solar Cell
Attached on All Panel
Supply Power to Devices and Charge Li+ Battery

Specifications of Solar Cell

Manufacture	Emcore (Tecster)
Dimensions	38.4×63.2mm
Efficiency	23.2%
Voltage	2120±1.0mV
Current	363mA

Li+ Battery

Small Size and Large Capacity
Low Memory Efficiency and High Performance for Cycle of Charge/Discharge Battery
4-parallel Configuration

Specifications of Li-ion Battery

Manufacture	NEC-TOKIN
Dimensions	33.6×8.7×47.0mm
Nominal Capacity	1130mAh×4
Nominal Voltage	3.8V
Weight	39.0g

Circuit Board

Cute-1.7 + APD EPS FM Top View

Cute-1.7 + APD EPS FM Bottom View

EPS FM (Board Back Up Model)

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