FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
Table 14. Output Voltage of SREG3
Address: 0111(34)
B7
B6
B5
B4
B3
B2
CP Off
EXTG On
SREG3 [V](35)
L
L
L
L
L
H
L
L
L
L
L
H
H
L
L
L
H
L
L
L
L
L
H
L
H
L
L
H
L
L
L
L
L
H
L
L
H
L
H
L
L
L
L
L
H
L
L
L
H
H
L
L
L
L
L
H
L
L
L
L
H
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
2.091
2.102
2.125
2.170
2.260
2.440
2.451
2.462
2.485
2.530
2.620
2.800
L
L
L
L
H
H
H
H
H
H
H
Notes
34. All combinations of input are not included.
35. The SREG1 and 3 output voltages are determined by the combination of external resistances connected to
SREGC1 and 3 (65.14KΩ between SREGO1 and SREGC1, 34.86KΩ between SREGC1 and GND, 73.84KΩ
between SREGO3 and SREGC3, and 26.16KΩ between SREGC3 and GND).
VG GENERATOR
VBATT
Start Up
VGATE
VGATE
VGATE
VGATE
VBATT
SWGATE
Step-Up
Pre Driver
GNDGATE
VG_select
VG_duty
Figure 10. Circuit when using a Step-Up Converter
When WAKE (int) goes High from Low, the start-up circuit
raises the VB voltage and outputs it to VGATE, then outputs
the VGATE voltage when PGOOD1 (int) goes High. The
charge pump circuit can be used for both Ni_mh and Li_ion
by setting the necessary registers. The charge pump circuit is
disabled by default.
The VGATE voltage can be set in the range of 6 V to 4.5 V
according to the combination of VGATESEL1 and 2 pin
connections. Refer to Table 16, VGATE Voltage Settings and
VGATESEL1 and 2 Pin Connection on page 23 for the VG
voltage settings.
When using a charge pump, please refer to Figure 11.
18730
Analog Integrated Circuit Device Data
Freescale Semiconductor
22
FREESCALE [ Freescale ]
