S-1702 Datasheet, PDF (19/45 Pages) Seiko Instruments Inc – Built-in overcurrent protection circuit

SUPER-LOW CURRENT CONSUMPTION 150 mA VOLTAGE REGULATOR WITH BUILT-IN HIGH-ACCURACY VOLTAGE DETECTOR AND RESET INPUT FUNCTION
Rev.2.2_01
S-1702 Series
2. 3 Hysteresis width (VHYS)
The hysteresis width is the difference between the detection voltage and the release voltage. Setting the
hysteresis width prevents malfunction caused by noise on the input voltage. The hysteresis width is internally
fixed and varies depending on the product type for details, refer to “Table 2 Output Types of VDOUT Pin”.
2. 4 Delay time (tD)
The delay time (tD) is a period from the input voltage flowing to the detector block has exceeded the release
voltage (+VDET), until the detector output voltage (VDOUT) inverts.
The internal delay type products (S-1702Axx, Bxx, Cxx, Dxx, Exx, Fxx, Gxx, Hxx, Jxx, Kxx) have delay time which
is internally fixed.
In external delay type products (S-1702Lxx, Mxx, Nxx, Pxx), the delay time (tD) can be changed by controlling the
capacitance value of the capacitor (CD) connected between the CD (RESX) and VSS pins.
For how to set the delay time (tD), refer to “3. 2 Delay circuit” in “3. Detector block” in “ Operation”.
V
+V_DET
V_OUT
When t_D = 90 μs
When t_D = 30 ms
V_DOUT
t
t_D
t_D
Remark This is the case when the regulator output voltage (V_OUT) is monitored by the detector.
Figure 21
2. 5 Through-type current
This is the current that flows instantaneously when the voltage detector detects and releases a voltage.
A large through-type current flows in CMOS output products (S-1702xBx, xCx, xEx, xFx, xHx, xJx).
A small through-type current flows in Nch open drain products (S-1702xAx, xDx, xGx).
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