Datasheet

LTC3859A
5
3859af
elecTrical characTerisTics
The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T
A
= 25°C. V
BIAS
= 12V, V
RUN1,2,3
= 5V, EXTV
CC
= 0V unless otherwise
noted. (Note 2)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Gate Driver
TG1,2 Pull-Up On-Resistance
Pull-Down On-Resistance
2.5
1.5
Ω
Ω
BG1,2 Pull-Up On-Resistance
Pull-Down On-Resistance
2.4
1.1
Ω
Ω
TG3 Pull-Up On-Resistance
Pull-Down On-Resistance
1.2
1.0
Ω
Ω
BG3 Pull-Up On-Resistance
Pull-Down On-Resistance
1.2
1.0
Ω
Ω
TG1,2,3 t
r
TG1,2,3 t
f
TG Transition Time:
Rise Time
Fall Time
(Note 6)
C
LOAD
= 3300pF
C
LOAD
= 3300pF
25
16
ns
ns
BG1,2,3 t
r
BG1,2,3 t
f
BG Transition Time:
Rise Time
Fall Time
(Note 6)
C
LOAD
= 3300pF
C
LOAD
= 3300pF
28
13
ns
ns
TG/BG t
1D
Top Gate Off to Bottom Gate On Delay
Synchronous Switch-On Delay Time
C
LOAD
= 3300pF Each Driver Bucks (Channels 1, 2)
Boost (Channel 3)
30
70
ns
ns
BG/TG t
1D
Bottom Gate Off to Top Gate On Delay
Top Switch-On Delay Time
C
LOAD
= 3300pF Each Driver Bucks (Channels 1, 2)
Boost (Channel 3)
30
70
ns
ns
t
ON(MIN)1,2
Buck Minimum On-Time (Note 7) 95 ns
t
ON(MIN)3
Boost Minimum On-Time (Note 7) 120 ns
INTV
CC
Linear Regulator
V
INTVCCVBIAS
Internal V
CC
Voltage 6V < V
BIAS
< 38V, V
EXTVCC
= 0V, I
INTVCC
= 0mA 5.0 5.4 5.6 V
V
LDOVBIAS
INTV
CC
Load Regulation I
CC
= 0mA to 50mA, V
EXTVCC
= 0V 0.7 2 %
V
INTVCCEXT
Internal V
CC
Voltage 6V < V
EXTVCC
< 13V, I
INTVCC
= 0mA 5.0 5.4 5.6 V
V
LDOEXT
INTV
CC
Load Regulation I
CC
= 0mA to 50mA, V
EXTVCC
= 8.5V 0.7 2 %
V
EXTVCC
EXTV
CC
Switchover Voltage EXTV
CC
Ramping Positive 4.5 4.7 V
V
LDOHYS
EXTV
CC
Hysteresis 200 mV
Oscillator and Phase-Locked Loop
f
25k
Programmable Frequency R
FREQ
= 25k; PLLIN/MODE = DC Voltage 115 kHz
f
65k
Programmable Frequency R
FREQ
= 65k; PLLIN/MODE = DC Voltage 375 440 505 kHz
f
105k
Programmable Frequency R
FREQ
= 105k; PLLIN/MODE = DC Voltage 835 kHz
f
LOW
Low Fixed Frequency V
FREQ
= 0V PLLIN/MODE = DC Voltage 320 350 380 kHz
f
HIGH
High Fixed Frequency V
FREQ
= INTV
CC
; PLLIN/MODE = DC Voltage 485 535 585 kHz
f
SYNC
Synchronizable Frequency PLLIN/MODE = External Clock
l
75 850 kHz
PGOOD1 Output
V
PGL1
PGOOD1 Voltage Low I
PGOOD1
= 2mA 0.2 0.4 V
I
PGOOD1
PGOOD1 Leakage Current V
PGOOD1
= 5V ±1 µA
V
PG1
PGOOD1 Trip Level V
FB1
with Respect to Set Regulated Voltage
V
FB1
Ramping Negative –13 –10 –7 %
Hysteresis 2.5 %
V
FB1
Ramping Positive 7 10 13 %
Hysteresis 2.5 %