LTC3899_15 Datasheet, PDF (13/38 Pages) Linear Technology – 60V Low IQ, Triple Output, Buck/Buck/Boost Synchronous Controller

Functional Diagrams
BUCK CHANNELS 1 AND 2
LTC3899
DRV_CC
FREQ
20µA
CLK2
VCO _CLK1
PFD
PLLIN/MODE
SYNC
DET
100k
20µA
DRVSET
EXTV_CC
2.00V
1.20V
V_BIAS
EN
EN
DRV_CC
R ^4R
INTV_CC
SQ
RQ
DROPOUT
DET
BOT
TOP ON
SHDN
BOOST1,2
TOP
TG1,2
SWITCHING
LOGIC
DRV_CC
BOT
SW1,2
BG1,2
GND
0.425V +
SLEEP
–
I_CMP
+ ^IR
+– –
3mV
2.8V
0.65V
SENSE1,2⁺
SENSE1,2^–
SLOPE COMP
V_FB1,2
EA
0.80V
TRACK/SS
3.5V
150nA
SHDN
RST
2(V_FB)
OV
FOLDBACK
0.88V
ITH1,2
10µA
TRACK/SS1,2
RUN1,2
SHDN
3899 FD
V_IN1,2
C_B
C_IN
C_OUT
V_OUT1,2
L
R_SENSE
R_B
R_A
C_C
C_C2
R_C
C_SS
DRV_CC LDO/
UVLO CONTROL
4.7V/ ^–
7.7V ₊
INTV_CC
LDO
For more information www.linear.com/LTC3899
3899f
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