MAX607ESA Maxim Integrated Products, MAX607ESA Datasheet - Page 9

• Manufacturer Part Number: MAX607ESA
• Description: IC CONV DCDC F/FLASH MEM 8-SOIC
• Manufacturer: Maxim Integrated Products

Specifications of MAX607ESA

• Applications: Converter, Flash Memory PCMCIA Cards
• Voltage - Input: 3 ~ 5.5 V
• Number Of Outputs: 1
• Voltage - Output: 12V, 3 ~ 12.5 V
• Operating Temperature: 0°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

The on/off times are determined by the input and output
voltages:
K is typically 3µs-V for the MAX606 and 6µs-V for the
MAX607. This factor is chosen to set the optimum
switching frequency and the one-cycle current limit,
which determines the no-load output ripple at low out-
put-to-input voltage differentials. The factor of 0.5 in the
off-time equation is the typical switch off-time ratio. This
ratio guarantees high efficiency under a heavy load by
allowing the inductor to operate in continuous-conduc-
tion mode. For example, a switch off-time ratio of 1
would cause the device to operate on the edge of dis-
continuous-conduction mode.
Figure 3. Functional Diagram
DC-DC Converters for Flash Memory/PCMCIA Cards
SHDN
FB
t
t
ON
OFF
LOCKOUT
VOLTAGE
UNDER-
MODE
DUAL
IN
= K / V
= 0.5 · K / (V
_______________________________________________________________________________________
INT/EXT
FB
5V/12V
OFF
MAX606
MAX607
Low-Profile, 5V/12V or Adjustable, Step-Up
IN
OUT
+ V
DIODE
- V
IN
EN
ON
INH
)
TIMING CIRCUIT
REF
t
ON
CONTROL
LOGIC
V
REF
t
OFF
To determine the actual switch off-time ratio for a par-
ticular device, measure t
then solve for the ratio by substituting these values into
the off-time equation.
Unlike PWM converters, the MAX606/MAX607 generate
variable-frequency switching noise. However, the
amplitude of this noise does not exceed the product of
the switch current limit and the output capacitor equiva-
lent series resistance (ESR). Traditional clocked-PFM or
pulse-skipping converters cannot make this claim.
The MAX606/MAX607 output voltage is pin-program-
mable to 5V and 12V, and also adjustable to voltages
between V
put, to GND for a 12V output, or to a resistive divider
between the output and GND for an adjustable output.
Always connect OUT to the output.
CURRENT-LIMIT
COMPARATOR
COMPARATOR
ERROR
IN
DRIVER
and 12.5V. Connect FB to IN for a 5V out-
Output Voltage Selection
ON
, t
R
OFF
LIM
, V
INTERNAL
POWER
1 SWITCH
IN
, and V
OUT
LX
PGND
SS
OUT
, and
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