ST1PS01
Datasheet
400 mA nano-quiescent synchronous step-down converter with digital voltage
selection and Power Good
Features
•
500 nA input quiescent current at VIN=3.6 V (not switching)
•
94% typical efficiency at 1 mA load (VIN=3.6 V, VOUT=3.3 V)
•
•
•
100% duty cycle
1.8 V to 5.5 V input operating range
Undervoltage lockout: 1.57 V (VIN falling, typ.)
•
•
•
•
•
•
•
Up to 400 mA output current capability
Low power control operation for the best efficiency
Embedded soft-start circuit
Tiny external components: L=2.2 µH typ.
Selectable output voltages: 0.625 V to 3.3 V
Output voltage Power Good
±1.5% output voltage accuracy (VOUT, TA = 25 °C)
•
•
Dynamic output voltage selection (D0, D1)
Available in Flip-Chip package
Applications
Product status link
ST1PS01
•
•
•
•
•
•
•
Wearable applications
Personal tracking monitors
Smart watches, sport bands
Energy harvesting, wireless sensors
Wearable and fitness accessories
Industrial sensors, portable low power devices
Single cell Li-Ion battery applications
•
•
Bluetooth® low energy
Zigbee
Description
The ST1PS01 is a nano-quiescent miniaturized synchronous step-down converter,
which is able to provide up to 400 mA output current with an input voltage ranging
from 1.8 V to 5.5 V.
This converter is specifically designed for applications where high efficiency, PCB
size and thickness are the key factors. The output voltage can be set using two digital
control inputs, a VOUT from 0.625 V to 3.3 V can be dynamically selected. Thanks to
the enhanced PCC (peak current control) the ST1PS01 reaches very high efficiency
conversion using just a 2.2 µH inductor and two small capacitors. Advanced design
circuitry is implemented to minimize the quiescent current. The device is available in
Flip-Chip package.
DS12799 - Rev 6 - June 2021
For further information contact your local STMicroelectronics sales office.
www.st.com
ST1PS01
Application schematic
1
Application schematic
Figure 1. ST1PS01 application schematic
Table 1. Typical external components
DS12799 - Rev 6
Component
Description
Value
Size - imperial (metric)
CIN
Ceramic capacitor with low ESR values
10 µF
0603 (1608)
COUT
Ceramic capacitor with low ESR values
10 µF
0603 (1608)
L
Inductor
2.2 µH
0806 (2016)
RPU
Pull-up resistor
1 MΩ
0402 (1005)
page 2/20
ST1PS01
Pin configuration
2
Pin configuration
Figure 2. Flip-Chip8 package (top through view)
1
A
D1
B
C
3
VIN
EN
D0
D
E
2
SW
GND
PGOOD
VOUT
Table 2. Pin description
DS12799 - Rev 6
Name
Bump name
VIN
A3
Input supply voltage. Bypass this pin to ground with a 10 µF capacitor
SW
C3
Switching output. Inductor connection
VOUT
E3
Sense pin used to monitor output voltage
EN
B2
Enable pin. High logic level turns on the IC. VIN referred
GND
D2
Ground
D1
A1
D0
C1
PGOOD
E1
Description
Output voltage selection inputs (Refer to the Section 5
Open drain output. It is in high impedance when the output voltage reaches 97.5% of the target VOUT
page 3/20
ST1PS01
Functional pin description
3
Functional pin description
GND
Device ground pin.
VIN
Supply voltage. This pin supplies power to the internal analog and digital circuitries when voltage is higher than
VUVLO. Bypass this pin to GND with a 10 μF ceramic capacitor. Input capacitor CIN must be chosen with low ESR
to reduce the input voltage ripple.
SW
Inductor connection to internal PMOS and NMOS switches.
VOUT
Output voltage sense input. It provides the feedback voltage level to the regulation circuitry. 10 µF output
capacitor COUT must be connected close to the pin or through a short trace and should have low ESR to reduce
the output voltage ripple.
EN
Enable pin. A logic low level on this pin disables the device. High level enables the device. Do not leave this pin
floating.
D0, D1
Output voltage selection pins. See the Section 5 for VOUT selection. Do not leave these pins floating. These pins
can be dynamically changed during operation.
PGOOD
Power Good open drain output. If used it requires a pull-up resistor to hold a high level signal. High impedance
indicates that VOUT is above proper good threshold.
DS12799 - Rev 6
page 4/20
ST1PS01
Maximum ratings
4
Maximum ratings
Table 3. Absolute maximum ratings
Symbol
Value
Unit
Power and signal supply voltage
- 0.3 to + 6.5
V
EN, D0, D1
Logic input pins
- 0.3 to + 6.5
V
VOUT, SW
Output signal monitoring and switching pins
-0.3 to VIN + 0.3
V
- 0.3 to + 6.5
V
Operating ambient temperature
-40 to 85
°C
TJ
Junction temperature
-40 to 125
°C
TSTG
Storage temperature
-55 to 150
°C
VIN
PGOOD
TAMB
Note:
Parameter
Power Good open drain output pin
Absolute maximum ratings are those values beyond which damage to the device may occur. Functional
operation under these conditions is not implied
Table 4. Thermal data
Symbol
RthJA
Parameter
Thermal resistance junction-ambient
Flip-Chip8
Unit
60
°C/W
Table 5. Recommended operating conditions
DS12799 - Rev 6
Symbol
Parameter
Min.
VIN
Input supply voltage
1.8
Typ.
Max.
Unit
5.5
V
page 5/20
ST1PS01
Electrical characteristics
5
Electrical characteristics
CIN= 10 µF, COUT= 10 µF, L=2.2 µH, RPU=1 MOhm, VIN=3.6 V, VEN= VIN, VOUT=1.8 V, TA=25 °C unless
otherwise specified.
Table 6. Electrical characteristics
Symbol
Parameter
Test conditions
Min.
Typ. Max. Unit
General section
EN=VIN,
IQ
Quiescent current
device does not switch (VOUT pin voltage > VOUT
setting value),
-
500 1000
nA
EN = GND, shutdown current into VIN
-
10
200
nA
VIN rising
-
1.63 1.72
V
VIN falling
1.51
1.57
-
V
Hysteresis
-
65
-
mV
100% mode leave threshold
VIN rising, 100% mode is disabled with VIN = VOUTnom
+ Vth100%+
-
300
-
100% mode enter threshold
VIN falling, 100% mode is entered with VIN = VOUTnom
+ Vth100%-
-
200
-
VIN= VOUT_min.+0.3 V (1.8 V min.) to 5.5 V
ISD
VUVLO
Vth100%+
Vth100%-
Shutdown current
Undervoltage lockout threshold
mV
Output voltage
VOUT
Output voltage range
Output voltages are selected with pins D0, D1
0.625
-
3.3
V
Output voltage accuracy
VIN = 3.6 V, whole VOUT range, IOUT=100 mA
-1.5
-
1.5
%
tONmin
Minimum on-time
VIN = 3.6 V, VOUT= 2 V, IOUT= 0 A
-
200
-
ns
tOFFmin
Minimum off-time
VIN=2.3V
-
50
-
ns
tstartupd
Start-up delay time
VEN from low to high, VIN = 3.6 V, VOUT = 1.8 V
-
1.7
-
ms
ROUTDIS
Output discharge MOSFET onresistance
VEN= GND
-
30
-
Ω
-
-
0.3
1.1
-
-
Logic inputs (EN, D0, D1)
VIL
Low level input voltage threshold
VIH
High level input voltage threshold
VIN=1.8 V to 5.5 V
V
Power switch
RDS(on)
High-side MOSFET onresistance
-
0.38 0.45
-
0.14
0.2
1.8 V ≤ VIN ≤ 5.5 V
500
-
1150
Reduced switch current limit during soft-start period
(typ. 400 µs)
180
280
360
Rising output voltage on VOUT pin, referred to VOUT
selected (D0, D1)
95
97.5
-
Hysteresis
-4
-3.2
-2.5
VIN = 3.6 V, Isw = 400 mA
Low-side MOSFET on-resistance
ILIM1
High-side MOSFET switch
current limit
ILIMSS
High-side MOSFET switch
current limit during soft-start
Ω
mA
Power Good output (PGOOD)
Vthpg
VthpgH
DS12799 - Rev 6
Power Good threshold voltage
%
page 6/20
ST1PS01
Electrical characteristics
Symbol
Parameter
VOL
Low level output voltage
Test conditions
Min.
1.8 V ≤ VIN ≤ 5.5 V, EN = GND, current into PGOOD
pin, IPGOOD = 4 mA
-
Typ. Max. Unit
-
0.23
V
Table 7. Output voltage settings
Device
ST1PS01AJR
ST1PS01BJR
ST1PS01CJR
ST1PS01DJR
ST1PS01EJR
ST1PS01FJR
ST1PS01GJR
ST1PS01HJR
D1
D0
VOUT
0
0
1.9 V
0
1
2.0 V
1
0
2.1 V
1
1
2.8 V
0
0
1.1 V
0
1
1.2 V
1
0
1.5 V(1)
1
1
1.7 V(1)
0
0
1.0 V
0
1
1.2 V
1
0
1.3 V
1
1
1.5 V(1)
0
0
1.8 V
0
1
2.3 V
1
0
2.5 V
1
1
2.8 V
0
0
1.8 V
0
1
2.7 V
1
0
3.0 V
1
1
3.3 V
0
0
1.05 V
0
1
1.25 V
1
0
1.35 V
1
1
1.55 V(1)
0
0
0.73 V
0
1
0.80 V
1
0
0.90 V
1
1
1.0 V
0
0
1.05 V
0
1
0.90 V
1
0
0.70 V
1
1
0.625 V
1. Vout can be dinamically selected when VIN=Vout selected+300 mV, at least.
DS12799 - Rev 6
page 7/20
ST1PS01
ST1PS01 block diagram
6
ST1PS01 block diagram
Figure 3. Block diagram
PGOOD
VIN
VIN
Cin
Bandgap/Bias
Vref
VIN
Vuvlo
-
UVLO comp.
+
VFB
-
Vref
+
Rpu
Output
discharge
EN
VOUT
VIN
VOUT
Peak and valley
CURRENT LIMIT
VSW
Min. ON time
D1
Vout
selection
logic
D0
Min. OFF time
Pulse freq.
detection
VFB
VOUT
VSW
Compensation
+
-
Vref
+
+
Driver/
anti -cross
conduction
circuitry
L
SW
Cout
High
current
mode
VSW
+
VIN
-
Vth100%
+
TON
Soft-start
ramp
DS12799 - Rev 6
PWM
CTRL
d Logic
Zero100%
crossing mode
comp.
comp.
-
GND
page 8/20
ST1PS01
Operation description
7
Operation description
The ST1PS01 is an ultra-low quiescent new generation buck converter. It targets a very small quiescent current
consumption (typical 500 nA) and it guarantees high efficiency operation even down to few microampere loads.
It is based on a hysteretic comparator that senses the coil ripple current that is held constant in all operation
modes. The device has seamless transition between PFM (pulse frequency modulation) and PWM (pulse width
modulation) mode with low ripple and good load transient response.
In order to maintain constant ripple current on the selected coil, the device changes switching frequency, which
also depends on input supply voltage. During PWM mode (heavy load), the device operates in continuous
conduction up to 400 mA and switching frequency can reach 2 MHz maximum.
7.1
Power save mode
At light load the device enters automatically power save mode with total current consumption from the input power
supply of 500 nA typical; during this condition most of the internal blocks are turned off in order to reach ultra-low
power consumption. During this time, the load current is supported by the output capacitor.
7.2
Output voltage
The device allows output voltage selection without external resistor divider. A couple of standard digital inputs are
used to configure the device to supply a fixed output voltage according to Section 5 . The VOUT pin must be
connected directly and as close as possible to the inductor terminal to obtain the best performance and get
the best output voltage regulation. The output voltage can be dynamically changed to implement voltage scaling.
7.3
Output discharge and UVLO
The device embeds a fast output discharge circuitry active when the enable pin is held to ground (EN=gnd)
or when the input supply voltage reaches the minimum voltage level set by the UVLO protection circuit
(undervoltage lock-out protection circuit). The UVLO rising threshold at 1.63 V (typ.) guarantees a proper device
supply voltage operation.
7.4
Soft-start and current limitation
The device embeds a fixed soft-start circuit active during a limited time period (few ms). This feature allows the
inrush current to be minimized from the power supply in case of weak source. During this period internal circuit
reduces to 280 mA the typical switch current limit.
The ST1PS01 embeds also a current limit on high-side MOSFET to protect the device against overload or
short-circuit on the output, during normal operation conditions. When the device enters 100% duty cycle operation
condition and an overload (or short-circuit) occurs, the output voltage is set in shutdown in order to limit the power
dissipation. To restart the device operation, a LOW to HIGH cycle on EN pin is necessary.
7.5
100% duty cycle operation
The device enters 100% duty cycle operation if the input voltage comes close to the selected output voltage.
During this mode, the regulator is turned off and output pin is directly connected to the input pin through the
high-side MOSFET. The output voltage follows the input level minus the voltage drop across the internal MOSFET
and the inductor. Once the input voltage exceeds the 100% duty cyle leave threshold, the device restarts to switch
and regulates the select output voltage again.
7.6
Power Good flag
The Power Good comparator monitors the selected VOUT voltage. The Power Good open drain output is in high
impedance when the VOUT reaches the correct voltage level while it switches to low level when VOUT falls below
the normal voltage level.
DS12799 - Rev 6
page 9/20
ST1PS01
Typical performance characteristics
8
Typical performance characteristics
Figure 4. Efficiency vs load, VOUT= 1.8 V
Figure 5. Efficiency vs VIN, VOUT= 1.8 V
100%
95%
90%
90%
80%
70%
85%
VIN 2.8V
VIN 3.2V
VIN 3.6V
Efficiency [%]
Efficiency [%]
60%
VIN 4.2V
50%
VIN 5V
40%
80%
Iout = 100µA
Iout = 1mA
75%
Iout = 50mA
Iout = 100mA
30%
Iout = 200mA
70%
L = 2.2µH
COUT = 10µF
20%
L = 2.2µH
COUT = 10µF
65%
10%
0%
0.001
60%
0.01
0.1
1
10
100
1000
2
2.5
3
3.5
4
Load current [mA]
4.5
5
5.5
6
Input Voltage [V]
Figure 6. Efficiency vs load, VOUT= 3.3 V
Figure 7. Efficiency vs VIN, VOUT= 3.3 V
100%
100%
90%
95%
90%
80%
VIN 3.6V
VIN 4.2V
85%
VIN 5V
Efficiency [%]
Efficiency [%]
70%
60%
Iout = 100µA
Iout = 1mA
80%
Iout = 50mA
Iout = 100mA
75%
50%
Iout = 200mA
L = 2.2µH
COUT = 10µF
70%
40%
L = 2.2µH
COUT = 10µF
65%
30%
20%
0.001
60%
0.01
0.1
1
Load current [mA]
DS12799 - Rev 6
10
100
1000
3.3
3.8
4.3
4.8
5.3
5.8
Input voltage [V]
page 10/20
ST1PS01
Typical performance characteristics
DS12799 - Rev 6
Figure 8. 100% mode, VOUT 1.8 V, IOUT 100 mA
Figure 9. 100% mode, VOUT 3 V, IOUT 10 mA
Figure 10. VOUT change, 1.8 V to 3 V to 1.8 V, IOUT 5
mA, VIN 3.6 V
Figure 11. Output ripple, VIN 3.6 V, VOUT 1.8 V, IOUT
10 uA
Figure 12. Output ripple, VIN 3.6 V, VOUT 1.8 V, IOUT
1 mA
Figure 13. Output ripple, VIN 3.6 V, VOUT 1.8 V, IOUT
50 mA
page 11/20
ST1PS01
Typical performance characteristics
DS12799 - Rev 6
Figure 14. Output ripple, VIN 3.6 V, VOUT 1.8 V, IOUT
150 mA
Figure 15. Output ripple, VIN 3.6 V, VOUT 1.8 V, IOUT
250 mA
Figure 16. Start-up VIN 3.6 V, VOUT 1.8 V, no load
Figure 17. Disable, Vin 3.6 V, VOUT 1.8 V, no load
Figure 18. Start-up, VIN 3.6 V, VOUT 1.8 V, IOUT 100
mA
Figure 19. Disable, VIN 3.6 V, VOUT 1.8 V, IOUT 100
mA
page 12/20
ST1PS01
Typical performance characteristics
Figure 20. Load transient, VIN 3.6 V VOUT 1.8 V, IOUT Figure 21. Load transient, VIN 3.6 V, VOUT 1.8 V, IOUT
50 uA to 10 mA
0 to 100 mA
Figure 22. Load transient, VIN 3.6 V, VOUT 1.8 V, IOUT 10 mA to 100 mA
DS12799 - Rev 6
page 13/20
ST1PS01
Package information
9
Package information
In order to meet environmental requirements, ST offers these devices in different grades of ECOPACK packages,
depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product
status are available at: www.st.com. ECOPACK is an ST trademark.
9.1
Flip-Chip 8 (1.14x1.44 mm) package information
Figure 23. Flip-Chip 8 (1.14x1.44 mm) package outline
DS12799 - Rev 6
page 14/20
ST1PS01
Flip-Chip 8 (1.14x1.44 mm) package information
Table 8. Flip-Chip 8 (1.14x1.44 mm) mechanical data
Symbol
Milimeters
Min.
Typ.
Max.
A
0.500
0.550
0.600
A1
0.170
0.200
0.230
A2
0.330
0.350
0.370
b
0.230
0.250
0.270
D
1.08
1.11
1.14
D1
E
0.624
1.38
1.41
E1
1.00
fE
0.205
fD
0.243
eE
0.250
eD
0.312
e
0.50
J
0.40
ccc
0.05
1.44
Figure 24. Flip-Chip 8 (1.14x1.44 mm) recommended footprint
DS12799 - Rev 6
page 15/20
ST1PS01
Flip-Chip 8 (1.14x1.44 mm) packing information
9.2
Flip-Chip 8 (1.14x1.44 mm) packing information
Figure 25. Flip-Chip 8 (1.14x1.44 mm) tape outline
Figure 26. Flip-Chip 8 (1.14x1.44 mm) tape orientation
DS12799 - Rev 6
1
A
MARKING
A
MARKING
1
MARKING
1
A
page 16/20
ST1PS01
Flip-Chip 8 (1.14x1.44 mm) packing information
Figure 27. Flip-Chip 8 (1.14x1.44 mm) reel outline
Table 9. Reel mechanical data
DS12799 - Rev 6
A max.
N min.
W1 max. [mm]
W2 max. [mm]
W3 min./max. [mm]
180
60
8.4
14.4
7.9/10.9
page 17/20
ST1PS01
Revision history
Table 10. Document revision history
Date
Version
31-Oct-2018
1
13-Dec-2018
2
13-Dec-2019
3
22-Jul-2020
4
Changes
Initial release.
Updated Section 8 Typical performance characteristics.
Added Section 9.2 Flip-Chip 8 (1.14x1.44 mm) packing information.
Updated Figure 22. Load transient, VIN 3.6 V, VOUT 1.8 V, IOUT 10 mA to 100
mA.
Updated the cover page, Section 5 Electrical characteristics,
Section 8 Typical performance characteristics.
Minor text changes.
22-Sep-2020
5
Updated Section Features.
Updated Figure 1. ST1PS01 application schematic.
28-Jun-2021
6
Updated Section 3 Functional pin description, Section 7.4 Soft-start and
current limitation and Table 6. Electrical characteristics.
Updated Table 7. Output voltage settings.
DS12799 - Rev 6
page 18/20
ST1PS01
Contents
Contents
1
Application schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
3
Functional pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
5
Electrical characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
7
Operation description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
7.1
Power save mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.2
Output voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.3
Output discharge and UVLO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.4
Soft-start and current limitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.5
100% duty cycle operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.6
Power Good flag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
8
Typical performance characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
9
Package information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
9.1
Flip-Chip8 (1.14x1.44 mm) package information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
9.2
Flip-Chip 8 (1.14x1.44 mm) packing information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
DS12799 - Rev 6
page 19/20
ST1PS01
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© 2021 STMicroelectronics – All rights reserved
DS12799 - Rev 6
page 20/20