Texas Instruments Boomer LM49360, User Manual

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General Type LDOS
The general “PERFECT” LDOs are optimized for supplying both analog and digital loads having ULTRA LOW NOISE (10µV
RMS
for I
OUT
>5mA) and excellent PSRR (75dB at 10kHz) performance. They can be programmed through the serial interface for different
output voltage values.
For fast discharging of output capacitors in shut down, the LDOs can connect a 300
Ω
pull-down resistor to the output. This resistor
is only connected when the LDO is disabled. See Table 20 for the register description.
In sleep mode, quiescent current is reduced to 30µA for energy saving. In this mode these LDOs should not be loaded with more
than 3-5mA of output current.
HILO LDO
LDO7 (HILO) has lowered output voltage range from 0.8V to 1.55V (step 50mV) controlled by 4 bit control signal as shown in LDO7
(HILO) output voltage selection table below. Typical output current is 2mA but maximum current can reach 20mA. For proper
operation, an input voltage of more than 2V is necessary. Hence, voltage drop on the pass transistor (dropout voltage) always
exceeds 0.45V and is not dependent on output current (in specified current range).
For fast discharging of output capacitors in shut down, the LDO7 (HILO) can connect a 300
Ω
pull-down resistor to the output. This
resistor is only connected when the LDO is disabled. See Table 20 for the register description.
Since the LDO7 (HILO) is based on the micro power LDO, no extra output capacitor is needed. However, for better dynamic
performance it is recommended that a capacitor in the 100nF to 1
μ
F range be used.
µPWR LDO
This LDO is primarily used for internal supply purposes and fixed to 1.8V, but may deliver up to 30mA of current also externally.
This LDO is ON even in Standby mode (with total PMU current consumption about 2uA) and the user may use it to supply some
backup/always on system(s).
TABLE 17. LDO1 — 6
Bank 0: CONFIG = Z (0x14h:LDO1)
→
(0x19h:LDO6)
Bank 1: CONFIG = H (0x24h:LDO1)
→
(0x29h:LDO6)
Bank 2: CONFIG = L (0x34h:LDO1)
→
(0x39h:LDO6)
Bits Field Description
4:0 LDO(1-6)*_VSEL This sets the output voltage of the corresponding LDO.
LDO*_VSEL Vout (V) LDO*_VSEL Vout (V)
00000 1.2 10000 2.1
00001 1.25 10001 2.2
00010 1.3 10010 2.3
00011 1.35 10011 2.4
00100 1.4 10100 2.5
00101 1.45 10101 2.6
00110 1.5 10110 2.65
00111 1.55 10111 2.7
01000 1.6 11000 2.75
01001 1.65 11001 2.8
01010 1.7 11010 2.85
01011 1.75 11011 2.9
01100 1.8 11100 2.95
01101 1.85 11101 3
01110 1.9 11110 3.1
01111 2 11111 3.3
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LM49360