ST STEVAL-1PS03A User manual

Introduction
The STEVAL-1PS03A is an evaluation board for a smart converter design able to deliver up to 400 mA output current from a 1.8
to 5.5 V input, with a 1.6 to 3.3 V dynamically adjustable output voltage.
The board features the ST1PS03AQTR nano-quiescent miniaturized synchronous step-down converter, which implements
enhanced peak current control (PCC) and advanced design circuitry to minimize quiescent current. The device embeds a
controlled load switch to supply a subsystem with VIN_AUX voltage rail.
The STEVAL-1PS03A demonstrates how highly efficient conversion can be achieved thanks to the ST1PS03AQTR (in a thin
TQFN12 package of 2.0x1.7 mm), a 2.2 μH inductor, and two small capacitors.
The ST1PS03AQTR key application benefits include high efficiency, and small PCB size and thickness. It is extremely suitable
for power conversion solutions in wearable applications and fitness accessories, personal tracking monitoring, smart watches,
sport bands, energy harvesting, wireless sensors, industrial sensors, portable low-power devices, single cell Li-ion battery
applications, as well as Bluetooth® low energy and Zigbee applications.
Figure 1. STEVAL-1PS03A evaluation board
Getting started with the STEVAL-1PS03A evaluation board based on
ST1PS03AQTR
UM2944
User manual
UM2944 - Rev 1 - October 2021
For further information contact your local STMicroelectronics sales office. www.st.com

1Getting started
1.1 Features
• 1.8 to 5.5 V input operating range
• Up to 400 mA output current capability
• Tiny external components: L = 2.2 µH typ
• Dynamically selectable output voltages from 1.6 to 3.3 V
• Output voltage Power Good
• Independent load switch (AUX control input)
• WEEE and RoHS compliant (hardware only)
1.2 Electrical performance specification
Table 1. Electrical performance specification (Ta = 25°C)
Symbol Parameter Min. Typ. Max. Unit
VIN Input supply voltage 1.8 3.6 5.5 V
VIN_AUX Auxiliary input supply voltage 0 VIN V
VOUT range Programmable by D0, D1 and D2 (see Table 2) 1.6 3.3 V
IOUT Output current 400 mA
IOUT_AUX Auxiliary output current 100 mA
Table 2. Output voltage settings
Device D2 D1 D0 VOUT
ST1PS03
0 0 0 1.8 V
0 0 1 3.3 V
0 1 0 2.8 V
0 1 1 2.7 V
1 0 0 3.0 V
1 0 1 2.1 V
1 1 0 1.6 V
1 1 1 2.5 V
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Getting started
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1.3 Input/output connector descriptions
This section provides the descriptions of the input/output connectors of the STEVAL-1PS03A.
•CN1: main input power supply
– VIN_F: positive input power force
– VIN_S: positive input power sense
– GND_F: ground input force
– GND_S: ground input sense
•CN9: auxiliary input power supply
– VIN_AUX: auxiliary input voltage
– GND: ground
•CN8: output voltage connector
– OUT_F: output voltage force
– OUT_S: output voltage sense
– GND_F: ground output force
– GND_S: ground output sense
•CN9: auxiliary output voltage connector
– OUT_F: auxiliary output voltage force
– OUT_S: auxiliary output voltage sense
– GND_F: ground output force
– GND_S: ground output sense
•CN2: load switch selection pin
– Place the jumper across AUX and HIGH to enable the load switch.
– Place the jumper across AUX and LOW to disable the load switch.
•CN3: ENABLE pin
– Place the jumper across EN and HIGH to enable the buck converter.
– Place the jumper across EN and LOW to disable the buck converter.
•CN4, CN5, CN6: output voltage selection pins (see Table 2, output voltage settings for VOUT selection).
Important: Do not leave these pins floating. They can be dynamically changed during operation.
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Input/output connector descriptions
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2Schematic diagrams
Figure 2. STEVAL-IPS03A circuit schematic
1
2
3
CN6
Header 3
1
2
3
CN5
Header 3
1
2
JP2
Header 2
1
2
3
4
CN1
Header 4
1
2
3
4
CN8
Header 4
10 uF
C1
10 uF
C3
1 MOhm
R1
2.2 uH
L1
JP1
TP1
1
2
3
4
CN7
Header 4
6
10 uF
C4
Vout2
1
2
3
CN3
Header 3
1
2
3
CN2
Header 3
1
2
3
CN4
Header 3
AUX
1
VIN
2
SW 3
GND 4
VOUT 8
VOUT2 6
PGOOD 7
VIN_AUX
5
D0
9
D1
10
D2
11
EN
12
ST1PS03AQTR
U1
DC-DC converter
Vin
Vin
Vin
Vin
Vin
D1
D2
D0
GND
GND
GND
GND
GND
Vin
Vin
Vout
Vout
Vout2
GND
GND
GND
GND
Vout_track
Sw
PGOOD
1
122
SHORT
SHORT 1203
Vout Vout_track
EN
AUX PG_Track
2
1
CN9
Header 2 10 uF
C2
Vin_AUX
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Schematic diagrams

3Bill of materials
Table 3. STEVAL-1PS03A1 bill of materials
Item Q.ty Ref. Value Description Manufacturer Part Number
1 1 R1 1 MΩ, SMD 0603, 0.25 W, ±1 % Thick film resistor Vishay CRCW06031M00FKEAHP
2 4 C1, C2,
C3, C4
10 µF, SMD 0603, 16 V, ±20 %,
X5R Ceramic capacitors TDK C1608X5R1C106M080AB
3 1 L1 2.2 µH, SMD 1008, 2.6 A, ±20 % Inductor for power
circuits TDK VLS252010HBX-2R2M-1
4 1 U1 ST1PS03AQTR, TQFN12
Nano-quiescent
synchronous step-
down converter
ST ST1PS03AQTR
5 1 TP1 Test pin, through hole Test point Multicomp TEST-1(Y)
6 2 JP2, CN9 2x1, through hole, 3 A, pitch
2.54 mm
Male SIL vertical
connectors Harwin M20-9993645
7 5
CN2,
CN3,
CN4,
CN5, CN6
3x1, through hole, 3 A, pitch
2.54 mm
Male SIL vertical
connectors Harwin M20-9993645
8 3 CN1,
CN7, CN8
4x1, through hole, 3 A, pitch
2.54 mm
Male SIL vertical
connectors Harwin M20-9993645
9 1 JP1 Short-circuit, through hole Soft tinned copper
wire RS Pro 390-549
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Bill of materials
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4Board layout
Figure 3. STEVAL-1PS03A top layer
Figure 4. STEVAL-1PS03A bottom layer
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Board layout
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5Board versions
Table 4. STEVAL-IPS03A versions
Finished good Schematic diagrams Bill of materials
STEVAL$1PS03AA (1) STEVAL$1PS03AA schematic diagrams STEVAL$1PS03AA bill of materials
1. This code identifies the STEVAL-1PS03A evaluation board first version.
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Board versions
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6Regulatory compliance
Formal Notice Required by the U.S. Federal Communications Commission
FCC NOTICE:
This kit is designed to allow:
(1) Product developers to evaluate electronic components, circuitry, or software associated with the kit to
determine
whether to incorporate such items in a finished product and
(2) Software developers to write software applications for use with the end product.
This kit is not a finished product and when assembled may not be resold or otherwise marketed unless all
required FCC equipment authorizations are first obtained. Operation is subject to the condition that this product
not cause harmful interference to licensed radio stations and that this product accept harmful interference. Unless
the assembled kit is designed to operate under part 15, part 18 or part 95 of this chapter, the operator of the kit
must operate under the authority of an FCC license holder or must secure an experimental authorization under
part 5 of this chapter 3.1.2.
The evaluation kit has been designed to comply with part 15 of the FCC Technical Rules. Operation is subject to
the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept
any interference received, including interference that may cause undesired operation.
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part
15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference
in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not
installed and used in accordance with the instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular installation.
Standard applied: FCC CFR 47 Part 15 Subpart B. Test method applied: ANSI C63.4 (2014).
Formal Product Notice Required by Industry Canada Innovation, Science and Economic Development
Canada compliance:
For evaluation purposes only. This kit generates, uses, and can radiate radio frequency energy and has not been
tested for compliance with the limits of computing devices pursuant to Industry Canada (IC) rules.
À des fins d'évaluation uniquement. Ce kit génère, utilise et peut émettre de l'énergie radiofréquence et n'a pas
été testé pour sa conformité aux limites des appareils informatiques conformément aux règles d'Industrie Canada
(IC).
This device has been tested with Innovation, Science and Economic Development RSS standards. Operation is
subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device
must accept any interference received, including interference that may cause undesired operation.
Standard applied: ICES-003 Issue 7 (2020), Class B. Test method applied: ANSI C63.4 (2014).
Cet appareil a été testé pour les normes RSS d'Innovation, Science et Développement économique. L'utilisation
est soumise aux deux conditions suivantes: (1) cet appareil ne doit pas causer d'interférences nuisibles, et (2)
cet appareil doit accepter de recevoir tous les types d’interférence, y comprises les interférences susceptibles
d'entraîner un fonctionnement indésirable.
Norme appliquée: NMB-003, 7e édition (2020), Classe B. Méthode d'essai appliquée: ANSI C63.4 (2014).
Formal product notice required by EU
This device is in conformity with the essential requirements of the Directive 2014/30/EU (EMC) and of the
Directive 2015/863/EU (RoHS).
Standards applied (Class B): EN 61000-6-1:2019, EN 61000-6-3:2007 + A1:2011 + AC:2012, EN 55032:2015 +
A1:2020, EN 55035:2017 + A11:2020, EN 61000-3-2:2019, EN 61000-3-3:2013 + A1:2019
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Revision history
Table 5. Document revision history
Date Revision Changes
19-Oct-2021 1 Initial release.
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Contents
1Getting started ....................................................................2
1.1 Features ......................................................................2
1.2 Electrical performance specification ...............................................2
1.3 Input/output connector descriptions ...............................................3
2Schematic diagrams ...............................................................4
3Bill of materials....................................................................5
4Board layout.......................................................................6
5Board versions ....................................................................7
6Regulatory compliance ............................................................8
Revision history ........................................................................9
List of tables ..........................................................................11
List of figures..........................................................................12
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Contents
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List of tables
Table 1. Electrical performance specification (Ta = 25°C) ..............................................2
Table 2. Output voltage settings ................................................................2
Table 3. STEVAL-1PS03A1 bill of materials ........................................................5
Table 4. STEVAL-IPS03A versions ..............................................................7
Table 5. Document revision history ..............................................................9
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List of figures
Figure 1. STEVAL-1PS03A evaluation board ......................................................1
Figure 2. STEVAL-IPS03A circuit schematic ......................................................4
Figure 3. STEVAL-1PS03A top layer............................................................6
Figure 4. STEVAL-1PS03A bottom layer .........................................................6
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Information in this document supersedes and replaces information previously supplied in any prior versions of this document.
© 2021 STMicroelectronics – All rights reserved
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