isl88550a Intersil Corporation, isl88550a Datasheet - Page 11

• Manufacturer Part Number: isl88550a
• Description: Synchronous Step Down Controller With Sourcing And Sinking Ldo Regulator
• Manufacturer: Intersil Corporation

OVP/UVP
SHDNA#
TON
STBY#
POK1
POK2
FB
BUCK ON/OFF
VTT ON/OFF
DECODER
SHUTDOWN
N
N
VTTR ON/OFF
QUAD LEVEL
ON/OFF
11
DECODER
0.7 x INTREF
BIAS
INTREF+10%
INTREF/2 + 10%
INTEREF/2 - 10%
BLANK
INTEREF-10%
INTREF
INTREF/2 + 10%
TRIG
INTEREF/2% - 10%
INTREF
1.16 X
OVP/UVP
COMPUTE
1-SHOT
ON TIME
LATCH
VIN
TIMER
20ms
FIGURE 21. FUNCTIONAL BLOCK DIAGRAM
t ON
POR
Q
POWER-DOWN
CURRENT
OUT 0.1V
LIMIT
ISL88550A
SS
+
+
DECODER
-
S
R
PHASE
VTT ILIM
FB
VOUT = 2.5V
Q1-SHOT
S
R
Q
ZERO CROSSING
1.0V
TRIG
t
Q
+
-
-
+
OFF
PGND2
OUT
DISCHARGE
INTREF
LOGIC
REFERENCE
VDD
VDD
REFIN/2
+
-
2V
+
-
PHASE
N
10kΩ
+
-
VDD - 1V
10kΩ
N
N
VDD
10Ω
October 1, 2007
BOOT
UGATE
PHASE
VDD
LGATE
PGND1
ILIM
SKIP#
OUT
AVDD
GND
REF
VTTS
REFIN
VTTI
VTT
PGND2
VTTR
FN6168.2