LP3470 Datasheet, PDF (3/8 Pages) National Semiconductor (TI) – Tiny Power On Reset Circuit

Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
V_CC Voltage
Reset Voltage
Output Current (Reset)
Operating Temperature Range
LP3470
−0.3V to +6V
−0.3V to +6V
10 mA
−20˚C to +85˚C
LP3470I
Junction Temperature (T_Jmax)
Power Dissipation (T_A = 25˚C) (Note
2)
θ_JA (Note 2)
Storage Temp. Range
Lead Temp. (Soldering, 5 sec)
ESD Rating (Note 3)
−40˚C to +85˚C
125˚C
300 mW
280˚C/W
−65˚C to +150˚C
260˚C
2 kV
Electrical Characteristics
Limits in standard typeface are for T_J = 25˚C, and limits in boldface type apply over the full operating temperature range, un-
less otherwise specified. V_CC = +2.4V to +5.0V unless otherwise noted.
Typ Min Max
Symbol
Parameter
Conditions
(Note (Note (Note Units
4)
5)
5)
V_CC
I_CC
V_RTH
Operating Voltage Range
V_CC Supply Current
Reset Threshold Voltage (Note 6)
V_CC = 4.5V
LP3470
0.5 5.5
V
16
30 µA
V_RTH
0.99
V_RTH
0.99
1.01
V_RTH
1.01
LP3470I
V_RTH V_RTH
V
V_RTH 0.99 1.01
V_RTH V_RTH
0.985 1.015
V_HYST
t_PD
t_RP
V_OL
Hysteresis Voltage (Note 7)
V_CC to Reset Delay
Reset Timeout Period (Note 8)
Reset Output Voltage Low
R₁
I_LEAK
External Pull-up Resistor
Reset Output Leakage Current
V_CC falling at 1 mV/µs
C₁ = 1 nF
V_CC = 0.5V; I_OL = 30 µA
V_CC = 1.0V; I_OL = 100 µA
V_CC =V_RTH −100 mV; I_OL = 4 mA
V_RTH V_RTH
35 15 65 mV
100
300 µs
2
1.0 3.5 ms
0.1
0.1
V
0.4
20 0.68 68 kΩ
0.15
1
µA
6
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Electrical specifications do not apply when operating the device
beyond its operating conditions.
Note 2: The maximum power dissipation must be derated at elevated temperatures and is dictated by T_Jmax (Maximum Junction Temperature), θ_JA (Junction to
Ambient Thermal Resistance), and T_A (Ambient Temperature). The maximum allowable power dissipation at any temperature is P_Dmax = (T_Jmax − T_A)/ θ_JA or the
number given in the Absolute Maximum Ratings, whichever is lower.
Note 3: The Human Body Model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin.
Note 4: Typical numbers are at 25˚C and represent the most likely parametric norm.
Note 5: Min. and Max. limits in standard typeface are 100% production tested at 25˚C. Min. and Max. limits in boldface are guaranteed through correlation using
Statistical Quality Control (SQC) methods. The limits are used to calculate National’s Average Outgoing Quality Level (AOQL).
Note 6: Factory-trimmed reset thresholds are available in 50 mV increments from 2.4V to 5.0V. Contact your National Semiconductor representative.
Note 7: V_HYST affects the relation between V_CC and Reset as shown in the timing diagram.
Note 8: t_RP is programmable by varying the value of the external capacitor (C₁) connected to pin SRT. The equation is: t_RP = 2000 x C₁ (C₁ in µF and t_RP in ms).
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