AN4397 Datasheet, PDF (1/19 Pages) STMicroelectronics – Evaluation board for SPV1050 ULP harvester

AN4397
Application note
Evaluation board for SPV1050 ULP harvester (buck-boost
architecture)
Domenico Ragonese
Introduction
The STEVAL-ISV020V1 is an evaluation board based on the ultralow power energy
harvester and battery charger SPV1050. For any detail related to the SPV1050 features and
performances please refer to the SPV1050 datasheet.
The evaluation board implements the buck-boost configuration of the DC-DC converter and
has the purpose of enhancing the SPV1050 based applications development by testing the
silicon performance thanks to many jumpers and test points, and by helping to find out the
best system configuration to make the SPV1050 device working at the most of efficiency.
The STEVAL-ISV020V1 board is optimized to:
 Harvest energy from PV panels supplying 2.6 V ≤ V_MP ≤ 9 V and 10 µA ≤ I_MP ≤ 20 mA.
 Charge a battery with the 3.7 V undervoltage protection threshold (V_UVP) and 4.2 V end
of charge voltage threshold (V_EOC).
Nevertheless, few easy changes on the application components (input and output resistor
partitioning, C_IN capacitor) allow to use a different PV panel and source (like TEG), and
a battery, by setting the V_{MPP_SET}, the V_UVP and the V_EOC thresholds according to the
source and load. More in detail, operating ranges can be extended as follows:
V_MP from 150 mV up to 18 V, I_MP up to 100 mA, V_UVP down to 2.2 V and V_EOC up to 5.3 V.
The STEVAL-ISV020V1 is shown in Figure 1.
Figure 1. STEVAL-ISV020V1 evaluation board
May 2014
DocID025515 Rev 1
1/19
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