AK5578EN Datasheet, PDF (54/70 Pages) Asahi Kasei Microsystems – 8-Channel Differential 32-bit  ADC

[AK5578]
■ LDO
The voltage range of TVDD is from 1.7 V to 1.98 V or from 3.0 V to 3.6 V. Set ON/OFF of the LDO by the
LDOE pin according to TVDD voltage (Table 21).
The internal LDO is switched ON/OFF depending on TVDD voltage range.
LDOE PDN LDO
VDD18 pin
Additional Voltage Range
to TVDD pin
L
L
OFF External Power Input 1.7-1.98 V
1.7-1.98 V
L
H
OFF External Power Input 1.7-1.98 V
1.7-1.98 V
H
L
OFF Pulled Down by 500  internally
H
H
ON LDO Voltage Output
3.0-3.6 V
3.0-3.6 V
Table 21. LDO Control
[1] TVDD=1.7-1.98 V, LDO is OFF (LDOE pin = “L”)
The internal LDO does not work properly when the TVDD voltage range is from 1.7 V to 1.98 V. Set the
LDOE pin to “L” to switch OFF the LDO. A 1.7 V - 1.98 V is supplied from the VDD18 pin for internal logic
circuits. The voltage difference between TVDD and VDD18 must be ±0.1 V or less.
[2] TVDD=3.0-3.6 V, LDO is ON (LDOE pin = “H”)
The internal LDO should be ON when the TVDD voltage range is from 3.0 V to 3.6 V. It will be the power
supply for the internal logic circuit. The VDD18 pin will be a connection terminal for a stabilization
capacitor. It is not possible to supply the power to external circuits from the VDD18 pin.
■ Reset
The AK5578 must be reset upon power up or when changing the clock setting or clock frequency. It can
be reset by the PDN pin or PW2-0 pins and RSTN bit or PW8-1 bits.
015016736-E-00
- 54 -
2015/12