Ublox SARA-N2 Series, Руководство по системной интеграции

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SARA-N2 / N3 series - System integration manual
UBX-17005143 - R13 Design-in Page 35 of 95
C1-Public
Reference Description Part number - Manufacturer
C1 10
µ
F capacitor ceramic X5R 0603 6.3 V GRM188R60J106ME47 - Murata
C2 100
µ
F capacitor tantalum 6.3V 15m  T520B107M006ATE015 - Kemet
L1 1
µ
H inductor 20% 3.1 A 60 m  TFM201610GHM-1R0MTAA - TDK
C3 100 nF capacitor ceramic X7R 0402 GCM155R71C104KA55 - Murata
C4 10 nF capacitor ceramic X7R 0402 GRT155R71C103KE01 - Murata
C5 56 pF capacitor ceramic C0G 0402 GRT1555C1E560JA02 - Murata
C6 15 pF capacitor ceramic C0G 0402 GJM1555C1H150JB01 - Murata
R1 100 k  resistor RC0402JR-07100KL - Yageo Phycomp
R2 1 k  resistor RC0402JR-071KL - Yageo Phycomp
T1 N-channel MOSFET DMG1012T - Diodes Incorporated
U1
High efficiency low power buck-boost regulator with
bypass mode
ISL9120IRTNZ - Intersil
Table 10: Suggested components for an alternative VCC voltage supply application circuit using a generic primary battery
2.2.1.4 Guidelines for VCC supply circuit design using a switching regulator
The use of a switching regulator is suggested when the difference from the available supply rail to the
VCC value is high: switching regulators provide good efficiency transforming a 12 V or greater voltage
supply to the typical 3.6 V value of the VCC supply.
The characteristics of the switching regulator connected to VCC pins should meet the following
prerequisites to comply with the module VCC requirements summarized in Table 5 :
• Power capability : the switching regulator with its output circuit must be capable of providing a
voltage value to the VCC pins within the specified operating range and must be capable of
delivering to VCC pins the specified average current during a transmission at maximum power
(see SARA-N2 series data sheet [1] and SARA-N3 series data sheet [2] ).
• Low output ripple : the switching regulator together with its output circuit must be capable of
providing a clean (low noise) VCC voltage profile.
• PWM mode operation : it is preferable to select regulators with Pulse Width Modulation (PWM)
mode. While in connected-mode Pulse Frequency Modulation (PFM) mode and PFM/PWM mode,
transitions must be avoided to reduce the noise on the
VCC voltage profile. Switching regulators
that are able to switch between low ripple PWM mode and high efficiency burst or PFM mode can
be used, provided the mode transition occurs when the module changes status from active-mode
to connected-mode: it is suggest to use a regulator that switches from the PWM mode to the
burst or PFM mode at an appropriate current threshold (e.g. 10 mA).