90E21 Datasheet, PDF (51/57 Pages) Integrated Device Technology – Single-Phase High-Performance Wide-Span Energy Metering IC

90E21/22/23/24
SINGLE-PHASE HIGH-PERFORMANCE WIDE-SPAN ENERGY METERING IC
Table-12 SPI Timing Specification (Continued)
t_DW
Minimum Data Width
t_PD
Output Delay
Note:
t_DF^{note 1}
Output Disable Time
1. Not applicable for three-wire SPI.
2. T means SCLK cycle. T=122ns. (Typical value for four-wire SPI)
6.3 POWER ON RESET TIMING
30T+10
14T
ns
15T+20
ns
16T+20
ns
V_H
V_L
DVDD
T₁
T₂
RESET
Figure-12 Power On Reset Timing Diagram
Table-13 Power On Reset Specification
Symbol
V_H
V_L
V_H-V_L
T₁
T₂
Description
Power On Trigger Voltage
Power Off Trigger Voltage
Hysteretic Voltage Difference
Delay Time After Power On
Delay Time After Power Off
6.4 ZERO-CROSSING TIMING
V
Min.
2.47
2.185
0.285
5
10
Typical
2.6
2.3
0.3
Max.
Unit
2.73
V
2.415
V
0.315
V
ms
µs
T_ZX
ZX
(Positive zero-crossing)
T_D
ZX
(Negative zero-crossing)
ZX
(All zero-crossing)
Figure-13 Zero-Crossing Timing Diagram
Electrical Specification
51
January 10, 2012