Datasheet

90E32AS ENHANCED POLY-PHASE HIGH-PERFORMANCE WIDE-SPAN ENERGY METERING IC
Electrical Specification 76 April 2, 2013
6.4 POWER ON RESET TIMING
In most case, the power of 90E32AS and MCU are both derived from
220V power lines. To make sure 90E32AS is reset and can work prop-
erly, MCU must force 90E32AS into idle mode firstly and then into nor-
mal mode. In this operation, RESET is held to high in idle mode and de-
asserted by delay T1 after idle-normal transition. Refer to Figure-23.
Figure-23 Power On Reset Timing (90E32AS and MCU are Powered on Simultaneously)
Figure-24 Power On Reset Timing in Normal & Partial Measurement Mode
Table-19 Power On Reset Specification
Symbol Description Min Typ Max Unit
V
H
Power On Trigger Voltage 2.5 2.7 V
T
0
Duration forced in idle mode after power on 1 ms
T
1
Delay time after power on or exit idle mode 5 16 40 ms
PM[1:0] Idle Mode Normal Mode
DVDD
MCU startup
Internal
P
O
R
T
1
T
0
DVDD
Internal POR
T
1
V
H