PRELIMINARY
CYW54907
15. Internal Regulator Electrical Specifications
15.1 Core Buck Switching Regulator
Note: Values in this data sheet are design goals and are subject to change based on device characterization results.
Note: Functional operation is not guaranteed outside of the specification limits provided in this section.
Table 33. Core Buck Switching Regulator (CBUCK) Specifications
Specification
Input supply voltage (DC)
PWM mode switching frequency
PWM output current
Notes
DC voltage range inclusive of disturbances.
CCM, load > 100 mA VBAT = 3.6V.
–
Min.
3.0
–
Typ. Max. Unit
3.6
4
4.8a
V
MHz
mA
mA
V
–
–
–
550
–
Output current limit
–
–
1400
1.35
–
Output voltage range
Programmable, 30 mV steps. Default = 1.35V.
Includes load and line regulation. Forced PWM mode.
Measure with 20 MHz bandwidth limit.
1.2
–4
–
1.5
4
PWM output voltage DC accuracy
PWM ripple voltage, static
%
7
20
mVpp
Static load. Max. ripple based on VBAT = 3.6V, Vout = 1.35V,
Fsw = 4 MHz,
2.2 μH inductor with min. effective L > 1.05 μH,
cap. + board total – ESR < 20 mΩ,
Cout > 1.9 μF, ESL<200 pH
PWM mode peak efficiency
PFM mode efficiency
Peak efficiency at 200 mA load.
10 mA load current.
78
70
–
86
81
–
–
%
%
Start-up time from power down
VIO already ON and steady. Time from REG_ON rising edge
to CLDO reaching 1.2V.
400
500
µs
External inductor
0806 size, 2.2 µH, DCR = 0.11Ω,
ACR = 1.18Ω @ 4 MHz.
Ceramic, X5R, 0402, ESR <30 mΩ at 4 MHz, 4.7 µF ±20%, 2.0b
6.3V.
For SR_VDDBAT5V pin, ceramic, X5R, 0603, ESR < 30 mΩ 0.67b
at 4 MHz, ±4.7 µF ±20%, 6.3V.
–
2.2
4.7
4.7
–
–
10c
–
µH
µF
µF
µs
External output capacitor
External input capacitor
Input supply voltage ramp-up time
0 to 4.3V.
40
–
a. The maximum continuous voltage is 4.8V. Voltages up to 6.0V for up to 10 seconds, cumulative duration, over the lifetime of the device are
allowed. Voltages as high as 5.0V for up to 250 seconds, cumulative duration, over the lifetime of the device are allowed.
b. Minimum capacitor value refers to the residual capacitor value after taking into account the part-to-part tolerance, DC-bias, temperature, and
aging.
c. Total capacitance includes those connected at the far end of the active load.
Document Number: 002-19312 Rev. *C
Page 65 of 95
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