Datasheet

2
LTC1875
1875f
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
I
VFB
Feedback Current (Note 4) ● 860 nA
V
FB
Regulated Output Voltage (Note 4) 0°C ≤ T
A
≤ 85°C 0.784 0.80 0.816 V
(Note 4) –40°C ≤ T
A
≤ 85°C ● 0.740 0.80 0.840 V
∆V
OVL
Overvoltage Trip Limit with Respect to V
FB
∆V
OVL
= V
OVL
– V
FB
● 20 60 110 mV
∆V
UVL
Undervoltage Trip Limit with Respect to V
FB
∆V
UVL
= V
FB
– V
UVL
● 20 60 110 mV
∆V
FB
/V
FB
Reference Voltage Line Regulation V
IN
= 2.65V to 6V (Note 4) 0.05 0.25 %/V
V
LOADREG
Output Voltage Load Regulation Measured in Servo Loop, V
ITH
= 0.9V to 1.2V ● 0.1 0.6 %
Measured in Servo Loop, V
ITH
= 1.6V to 1.2V ● –0.1 –0.6 %
V
IN
Input Voltage Range ● 2.65 6 V
I
Q
Input DC Bias Current (Note 5)
Pulse Skipping Mode 2.65V < V
IN
< 6V, V
SYNC/MODE
= 0V, I
OUT
= 0A 270 365 µA
Burst Mode Operation V
SYNC/MODE
= V
IN
, I
OUT
= 0A 15 22 µA
Shutdown V
RUN
= 0V, V
IN
= 6V 0 1 µA
f
SYNC
SYNC Capture Range 350 750 kHz
f
OSC
Oscillator Frequency V
FB
≥ 0.7V 495 550 605 kHz
V
FB
= 0V 80 kHz
I
PLLLPF
Phase Detector Output Current
Sinking Capability f
PLLIN
< f
OSC
● 3 10 20 µA
Sourcing Capability f
PPLIN
> f
SOC
● –3 –10 –20 µA
R
PFET
R
DS(ON)
of P-Channel FET I
SW
= 100mA, V
IN
= 5V 0.28 0.35 Ω
R
NFET
R
DS(ON)
of N-Channel FET I
SW
= –100mA, V
IN
= 5V 0.35 0.4 Ω
I
PK
Peak Inductor Current V
FB
= 0.7V, Duty Cycle < 35%, V
IN
= 3V 1.6 2.15 2.75 A
I
LSW
SW Leakage V
RUN
= 0V, V
SW
= 0V or 6V, V
IN
= 6V ±0.01 ±2.5 µA
V
SYNC/MODE
SYNC/MODE Threshold ● 0.2 1.0 1.5 V
I
SYNC/MODE
SYNC/MODE Leakage Current ±0.01 ±1 µA
(Note 1)
ORDER PART
NUMBER
LTC1875EGN
T
JMAX
= 125°C, θ
JA
= 110°C/ W, θ
JC
= 40°C/W
The ● denotes specifications which apply over the full operating
temperature range, otherwise specifications are T
A
= 25°C. V
IN
= 3.6V unless otherwise noted.
ABSOLUTE MAXIMUM RATINGS
W
WW
U
PACKAGE/ORDER INFORMATION
W
U
U
ELECTRICAL CHARACTERISTICS
Input Supply Voltage .................................. –0.3V to 7V
I
TH
, PLL_LPF Voltages............................. –0.3V to 2.7V
RUN/SS, V
FB
Voltages ............................... –0.3V to V
IN
SYNC/MODE Voltage ................................. –0.3V to V
IN
(V
PVIN
– V
SWP
) Voltage............................... –0.3V to 7V
V
SWN
Voltage.............................................. –0.3V to 7V
P-Channel Switch Source Current (DC) .................... 2A
N-Channel Switch Sink Current (DC) ........................ 2A
Peak Switching Sink and Source Current ................. 3A
Operating Ambient Temperature Range
(Note 2) ............................................. –40°C to 85°C
Junction Temperature (Note 3, 6)........................ 125°C
Storage Temperature Range ................ –65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
TOP VIEW
GN PACKAGE
16-LEAD PLASTIC SSOP
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
SGND
RUN/SS
V
FB
I
TH
SWP1
SWN1
PGND1
PV
IN1
PLL_LPF
SYNC/MODE
PGOOD
SV
IN
SWP2
SWN2
PGND2
PV
IN2
GN PART
MARKING
1875
Consult LTC Marketing for parts specified with wider operating temperature ranges.