S-8340A25AFT-T2-X Datasheet, PDF (24/55 Pages) Seiko Instruments Inc – SWITCHABLE SWITCHING REGULATOR CONTROLLER

STEP-UP, 600 kHz, PWM CONTROL OR PWM/PFM SWITCHABLE SWITCHING REGULATOR CONTROLLER
S-8340/8341 Series
Rev.4.0_01
 Standard Circuit
(1) Using MOS FET
L
V IN
Nch Power
MOS FET
EXT
SENSE
R SENSE
SD
VDD
V O UT
Triangular w ave
oscillation circuit
PW M comparator
Phase
com pensation
circuit
IC internal power
supply
VOUT
RS
CS
120 mV
Shutdown
circuit
PW M, PW M/PFM
switching control
circuit
Soft-start
circuit
CC
R1
Error am plifier
R2
VREF =1.0 V
V o lta ge /c ur r e nt
reference
+
CL
VSS
ON/OFF
CSS
CVREF
CSS
C VREF
Single ground
Figure 14 Output Voltage Fixed Output Type
L
VIN
Nch Power
MOS FET
EXT
SENSE
R SENSE
SD
VDD
Triangular w ave
oscillation circuit
PW M comparator
Pc _ohma spee _{n s a ti o n}
circuit
IC internal pow er
supply
V O UT
RS
CS
120 mV
Shutdown
circuit
PW M, PW M/PFM
switching control
circuit
Soft-start
circuit
Error am plifier
VREF =1.0 V
V o lta ge /c ur r e nt
reference
CFB
RFB1
+
FB
CL
RFB2
VSS
ON/OFF
CSS
CSS
CVREF
C VREF
Single ground
Figure 15 Output Voltage External Setting Type
24