S-1702 Datasheet, PDF (27/45 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
(1)
Hysteresis width (V_HYS)
V_SENSE (V_IN)^*1
(2) (3) (4) (5)
V_DD
B
A
Release voltage (+V_DET)
Detection voltage (–V_DET)
Lowest operating voltage
V_SS
VDOUT
V_SS
t_D
*1. When the SENSE pin is connected to the VIN pin.
Figure 29 Operation
3. 1. 1 Regulator output voltage (VOUT) detection types (S-1702Axx, Bxx, Cxx, Dxx, Lxx, Mxx)
Each detector block of S-1702Axx, Bxx, Cxx, Dxx, Lxx, and Mxx detects the regulator output voltage (VOUT).
VIN
V_IN
V_OUT
Current
supply
R_a
V_ref
+
−
R_b
Delay ^VDOUT ^Output
circuit
circuit
VDOUT
CD ^*1
C_D
VSS
N₁
R_c
V_SS VSS
*1. S-1702Lxx and S-1702Mxx only
Figure 30 Block Diagram (Regulator Output Voltage (VOUT) Detection Type)
Caution If the input voltage or load current changes transiently, undershoot or overshoot occurs in
the regulator output voltage (VOUT). In the product types that the regulator output voltage is
detected by the detector, if the output voltage reaches the detection voltage or less due to
undershoot, the detector operates so that a reset signal may be output. To prevent this, set
the value of the capacitor so that the value of undershoot is the minimum, or set the voltage
range in which the difference of the output voltage and the detection voltage is undershoot
or more.
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