ltc4221 Linear Technology Corporation, ltc4221 Datasheet - Page 12

• Manufacturer Part Number: ltc4221
• Description: Dual Hot Swap Controller/power Sequencer With Dual Speed, Dual Level Fault Protection
• Manufacturer: Linear Technology Corporation

OPERATIO
LTC4221
12
PWRGD1
PWRGD2
SENSE1
SENSE2
FILTER
TIMER
GATE1
GATE2
FAULT
V
V
V
OUT1
OUT2
ON1
ON2
CC n
UVLO
V
ON(OFF)
RESET
V
1
CC n
V
V
ON1 > V
ON(OFF)
2
CC n (UVL)
+ ΔV
U
CLEARS V
100μA
100μA
V
ON(RESET)
ON(OFFHYST)
+ ΔV
ON(RESET)
OFF
CC n (UVL)
ON(OFFHYST)
+ ΔV
+ ΔV
ON2 > V
CHECK GATE < V
3
ON(RESETHYST)
V
ON(RESETHYST)
GATE(OV)
ON1 > V
CHECK GATE < V
4
ON(OFF)
V
V
GATE(OV)
ON(OFF)
ON(OFF)
, + ΔV
GATE(OV)
1.9μA
INITIAL TIMING
ON(OFFHYST)
+ ΔV
GATE(OV)
, TIMER < 0.4V
ON(OFFHYST)
Figure 1. LTC4221 Operation
, TIMER < 0.4V
,
FB1 > V
,
V
TMR(H)
FB(UV)
V
TMR(L)
FB2 > V
+ ΔV
9mV
FB(HYST)
FB(UV)
5 6 7
25mV
ELECTRONIC CIRCUIT BREAKER ARMED, CHECK FILTER < V
FAULT > V
CHANNEL 1
START-UP
20μA
9.5μA
+ ΔV
8
FB(HYST)
FAULT(TH)
9mV
9.5μA
9 10
CHANNEL 1 SLOW COMPARATOR ARMED
CHANNEL 2
START-UP
20μA
V
V
SENSE(SC)
SENSE(FC)
+ ΔV
V
FILTER(TH)
FAULT(HYST)
11 12 13
CHANNEL 2 SLOW COMPARATOR ARMED
105μA
NORMAL
14
FB1 < V
FB2 < V
FB(UV)
FB(UV)
FAULT
1.8μA
V
ON1(RESET)
FILTER(TH)
15
RESET
,
4221 F01
4221fa