1
DESCRIPTION
Demonstration Circuit DC1463A is a Switching Power Manager with USB On-the-Go and Overvoltage Protection
featuring the LTC
®
4160.
PERFORMANCE SUMMARY
Specifications are at T
A
= 25°C
SYMBOL PARAMETER
CONDITIONS
MIN TYP
MAX
UNITS
VBUS
Bus Input Voltage Range
4.35
6
V
V(LDO3V3) 3.3V LDO Output
VOUT > 3.5V
3.1
3.4
V
V(BAT)
Battery Float Voltage
LTC4160 Constant Voltage Mode
LTC4160-1 Constant Voltage Mode
4.15
4.05
4.23
4.13
V
I(BAT)
Battery Charge Current
Constant Current Mode, R
PROG
= 2.00k
485
515 mA
VOUT
Output Voltage
ILIM[1..0] = 01b, I(VOUT) ≤ 1.25A, V(BAT) > 3.6V
I(VOUT) ≤ 1.25A, V(BAT) < 3.6V
V(BAT)
3.6V
VBAT
+
0.45V
V
V
V
OTG
VBUS voltage in OTG mode I(VBUS) ≤ -500mA
4.5
5
5.5
V
QUICK START PROCEDURE
Refer to Figure 1 for the proper measurement
equipment setup and jumper settings and follow the
procedure below.
NOTE.
When measuring the input or output voltage ripple, care
must be taken to avoid a long ground lead on the oscilloscope
probe. Measure the input or output voltage ripple by touching the
probe tip directly across the VBUS or VOUT(x) and GND terminals.
See Figure 2 for proper scope probe technique.
1.
Set all jumpers as shown in Figure 1 and LD1 =
0A, PS1 = 5V, LD2 = 0A, LD3 = 0A, PS2 = 3.6V.
Observe VOUT (VM4), LDO3V3 (VM3), and
V(NTC) (VM2). The LTC4160 is operating as
USB power manager. The current from PS1 will
try to be the charging current * (3.6V/5V), or ap-
proximately 400mA, but will be limited by the in-
put current limiter to ~ 100mA.
2.
Increase LD3 to 80mA, and LD2 to 25mA. Ob-
serve VOUT(VM4), I(VUSB) (AM1) and LDO3V3
(VM3). Set LD2 to 0A. The loads on VOUT and
LDO3V3 are now reducing the charge current
further.
3.
Increase LD3 to 250mA. Observe VOUT(VM4),
I(VUSB) (AM1). The load on VOUT will engage
the input current limit, and VOUT will drop until
the ideal diode engages to provide the difference
current.
DEMO CIRCUIT 1463A
QUICK START GUIDE
LTC4160EPDC / LTC4160EPDC-1
Switching Power Manager with USB
On-the-Go and Overvoltage Protection