Dual Step-Down Controllers with Saturation

Protection, Dynamic Output, and Linear Regulator

10

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ELECTRICAL CHARACTERISTICS (continued)

(Note 4)

PARAMETER

SYMBOL

CONDITIONS

MIN

MAX

UNITS

High

0.4V

Open

3.15

3.85

REF

1.65

2.35

Four-Level Input Logic Levels

TON, OVP/UVP, LSAT,

SKIP,

FBLANK

Low

0.5

V

(LDOOUT),

and the linear-regulator input supply (LDOIN) is internally connected to the battery voltage input (V+).

Note 2: When the inductor is in continuous conduction, the output voltage has a DC regulation level higher than the error-comparator

threshold by 50% of the ripple. In discontinuous conduction (SKIP = GND, light load), the output voltage has a DC regulation

level higher than the trip level by approximately 1.5% due to slope compensation.

Note 3: On-time and off-time specifications are measured from 50% point to 50% point at the DH_ pin with LX_ = GND, VBST_ = 5V,

and a 250pF capacitor connected from DH_ to LX_. Actual in-circuit times may differ due to MOSFET switching speeds.

Note 4: Specifications to -40°C are guaranteed by design, not production tested.

OUT2 EFFICIENCY vs. LOAD CURRENT

LOAD CURRENT (A)

1

0.1

55

60

65

70

75

80

85

90

95

100

50

0.01

10

SKIP = GND

2.5V OUTPUT VOLTAGE (OUT2)

vs. LOAD CURRENT

LOAD CURRENT (A)

4

3

2

1

2.49

2.50

2.51

2.52

2.53

2.54

2.55

2.48

05

SKIP = GND

OUT1 EFFICIENCY vs. LOAD CURRENT

LOAD CURRENT (A)

1

0.1

55

60

65

70

75

80

85

90

95

100

50

0.01

10

SKIP = GND

Typical Operating Characteristics