RNA51958A Datasheet, PDF (8/12 Pages) Renesas Technology Corp – Voltage Detecting, System Resetting IC Series

RNA51958A,B
Notice for use
About the Power Supply Line
1. About bypass capacitor
Because the ripple and the spike of the high frequency noise and the low frequency are superimposed to the power
supply line, it is necessary to remove these.
Therefore, please install C₁ and C₂ for the low frequency and for the high frequency between the power supply line
and the GND line as shown in following figure 5.
V_CC
C₁⁺ C₂
R₁
Example of ripple
noise measures ^Vin
R₂
Input
Power-supply
RNA51958
Output
GND
Delay capacitor
Cd
Figure 5 Example of Ripple Noise Measures
2. The sequence of voltage impression
Please do not impress the voltages to the input terminals earlier than the power supply terminal. Moreover, please
do not open the power supply terminal with the voltage impressed to the input terminal.
(The setting of the bias of an internal circuit collapses, and a parasitic element might operate.)
About the Input Terminal
1. Setting range of input voltage
The following voltage is recommended to be input to the input terminal (pin 2).
about 0.8 (V) < Vin < V_CC – 0.3 (V) ... at V_CC ≤ 7 V
about 0.8 (V) < Vin < 6.7 (V) ............. at V_CC > 7 V
2. About using input terminal
Please do an enough verification to the transition characteristic etc. of the power supply when using independent
power supply to input terminal (pin 2).
V_CC
Vin is decided to the V_CC subordinating,
Power-supply ^{and operates in the range}
about 0.8 (V) < Vin < V_CC – 0.3 (V).
Input
Output
Vin
RNA51958
GND
Delay capacitor
Cd
Figure 6 Recommended Example
REJ03D0915-0100 Rev.1.00 Mar 02, 2009
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