Specifications with standard typeface are for T

perature Range (T

VREF = 1.35V.

Symbol

Parameter

Conditions

Min

Typ

Max

Units

V

SYNC_H

SYNC/MODE Positive

Going Threshold Voltage

0.85

1.3

V

V

SYNC_L

SYNC/MODE Negative

Going Threshold Voltage

0.4

0.80

V

V

SEL_H

V

Threshold Voltage

0.80

1.3

V

V

SEL_L

V

Threshold Voltage

0.4

0.75

V

I

SEL

VSEL Pull Down Current

VSEL = 1.2V

0.70

2

µA

I

REF

Input current into VREF pin

15

150

nA

f

sync

SYNC/MODE Clock

Frequency Range

(Note 9)

500

1000

kHz

F

OSC

Internal Oscillator

Frequency

LM2608ATL-1.3/1.8, PWM

Mode

510

610

690

kHz

T

min

Minimum ON-Time of P FET

Switch in PWM Mode

200

ns

Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings are conditions for which the device is intended

to be functional, but parameter specifications may not be guaranteed. For guaranteed specifications and associated test conditions, see the Min and Max limits and

Conditions in the Electrical Characteristics table. Electrical Characteristics table limits are guaranteed by production testing, design or correlation using standard

Statistical Quality Control methods. Typical (Typ) specifications are mean or average values from characterization at 25˚C and are not guaranteed.

Note 2: Thermal shutdown will occur if the junction temperature exceeds the 150˚C maximum junction temperature of the device.

Note 3: Thermal resistance specified with 2 layer PCB(0.5/0.5 oz. cu).

Note 4: The LM2608 is designed for cell phone applications where turn-on after system power-up is controlled by the system processor and internal UVLO (Under

Voltage LockOut) circuitry is unnecessary. The LM2608 has no UVLO circuitry and should be kept in shutdown by holding the EN pin low until the input voltage

exceeds 2.8V. Although the LM2608 exhibits safe behavior while enabled at low input voltages, this is not guaranteed.

Note 6: The hysteresis voltage is the minimum voltage swing on FB that causes the internal feedback and control circuitry to turn the internal PFET switch on and

then off, during test mode.

Note 7: Current limit is built-in, fixed, and not adjustable. If the current limit is reached while the output is pulled below about 0.7V, the internal PFET switch turns

off for 2.5 µs to allow the inductor current to diminish.

Note 8: EN is a Schmitt trigger digital input with logic thresholds that are independent of supply voltage at the VDD pin.

Note 9: SYNC driven with an external clock switching between VDD and GND. When an external clock is present at SYNC, the IC is forced into PWM mode at the

external clock frequency. The LM2608 synchronizes to the rising edge of the external clock.

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