LTC3850EUF#PBF Linear Technology, LTC3850EUF#PBF Datasheet - Page 10

• Manufacturer Part Number: LTC3850EUF#PBF
• Description: IC CNTRLR STP DWN SYNC 28-QFN
• Manufacturer: Linear Technology
• Series: PolyPhase®r
• Type: Step-Down (Buck)r

Specifications of LTC3850EUF#PBF

• Internal Switch(s): No
• Synchronous Rectifier: Yes
• Number Of Outputs: 2
• Voltage - Output: 0.8 ~ 23.3 V
• Current - Output: 100mA
• Frequency - Switching: 250kHz ~ 780kHz
• Voltage - Input: 4 ~ 24 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 28-QFN
• Primary Input Voltage: 24V
• No. Of Outputs: 2
• Output Current: 100mA
• No. Of Pins: 28
• Operating Temperature Range: -40°C To +85°C
• Msl: MSL 1 - Unlimited
• Supply Voltage Range: 4V To 24V
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -

LTC3850/LTC3850-1
PIN FUNCTIONS
MODE/PLLIN (Pin 27/Pin 24/Pin 25): Force Continuous
Mode, Burst Mode, or Pulse-Skipping Mode Selection
Pin and External Synchronization Input to Phase Detector
Pin. Connect this pin to SGND to force both channels into
the continuous mode of operation. Connect to INTV
enable pulse-skipping mode of operation. Leaving the
pin floating will enable Burst Mode operation. A clock on
the pin will force the controller into continuous mode of
operation and synchronize the internal oscillator.
FUNCTIONAL DIAGRAM
10
I
FREQ/PLLFLTR
LIM
0.8V
REF
V
IN
PLL-SYNC
0.55V
–
SLEEP
I
51k
THB
MODE/PLLIN
1
+
I
CMP
MODE/SYNC
DETECT
+
–
OSC
INTV
CC
+
EA
+
3k
–
SLOPE COMPENSATION
SLOPE RECOVERY
ACTIVE CLAMP
S
R
–
+
UVLO
Q
I
REV
I
TH
0.64V
R
–
–
C
SS
C
C1
F
0.8V
+
+
EXTV
CC
–
1.2V
–
CC
to
RUN
RUN
F
4.7V
FCNT
+
RUN
+
ON
OV
FREQ/PLLFLTR (Pin 28/Pin 25/Pin 26): The Phase-Locked
Loop’s Low-Pass Filter is Tied to This Pin. Alternatively, this
pin can be driven with a DC voltage to vary the frequency
of the internal oscillator.
Exposed Pad (Pin 29, UF/UFD Packages Only): Signal
Ground. Must be soldered to PCB, providing a local ground
for the control components of the IC, and be tied to the
PGND pin under the IC.
THROUGH
SWITCH
SHOOT
BURSTEN
LOGIC
ANTI-
REG
AND
TK/SS
5V
1.3 µ A
C
SS
UV
OV
+
–
+
–
38501 FD
SENSE
SENSE
BOOST
PGOOD
INTV
C
PGND
SGND
V
SW
VCC
V
TG
BG
IN
FB
0.74V
0.86V
CC
+
–
0.5 µ A
C
D
B
B
R2
R1
+
C
IN
M1
M2
V
L1
IN
INTV
CC
+
V
OUT
C
OUT
38501fc