MC34652EF Freescale Semiconductor, MC34652EF Datasheet - Page 15

• Manufacturer Part Number: MC34652EF
• Description: IC CTRLR HOT SWAP NEG V 16-SOIC
• Manufacturer: Freescale Semiconductor
• Type: Hot-Swap Switchr

Specifications of MC34652EF

• Applications: General Purpose
• Internal Switch(s): Yes
• Current Limit: 2.0A
• Voltage - Supply: 15 V ~ 80 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

BOARD REMOVAL
soon as the 34652’s input voltage reaches the undervoltage
turn-off threshold, the undervoltage detection circuit activates
and the Power MOSFET turns off for having violated one of
the start-up conditions (list on
UNDERVOLTAGE
undervoltage falling threshold for more than 1.0 ms, an
undervoltage fault is detected and one of the start-up
conditions (list on
the Power MOSFET and deactivates the power good output
signals, disabling the load (Point A in
stays in this state until the voltage on the UV pin rises above
the undervoltage rising threshold for more than 1.0 ms,
signaling that the supply voltage is in the normal operation
range (Point B in
initiates as described on
detection circuit is also equipped with a 1.0 V hysteresis
when in default mode. The hysteresis value depends on the
undervoltage detection threshold and can be calculated as
follows:
Analog Integrated Circuit Device Data
Freescale Semiconductor
When the board is removed, its power ramps down. As
When the voltage on the UV pin drops below the
V
UVHY
V
V
Filter = 1.0 ms
Filter = 1.0 ms
Temp > 160°C
PWR
PWR
Filter = 12 μs
= V
< V
> V
UV (
OV(OFF)
UV(OFF)
RISING
MOSFET → OFF
MOSFET → OFF
Figure
MOSFET → OFF
Undervoltage
page
Overvoltage
Shutdown
Thermal
PG = 0
PG = 0
PG = 0
)
*
12) is violated. The 34652 turns off
[1 - (1.3 V -
14). Then a new start-up sequence
page
V
Filter = 1.0 ms
PWR
V
V
Filter = 1.0 ms
Filter = 1.0 ms
PWR
PWR
page
Temp < 135°C
12. The undervoltage
Filter = 12 μs
> V
< V
< V
UV(ON)
UVLOF
V
12).
OV(ON)
UVCHY
Figure
POR is generated
MOSFET → OFF
V
Filter = 1.0 ms
PWR
) / 1.3 V ]
Power Off
• Thermal Shutdown < 160°C
A signal “set” is generated to check
PG = 0
14). The 34652
resistors on UV, ILIM, ICHG, and
N = 0
> V
Start-Up Conditions
TIMER pins and 128 μs later
• V
• V
PROTECTION FEATURES
UVLOR
• DISABLE = 0
Filter = t
PWR
PWR
Ext. Resistor Check
Figure 13. State Diagram
N = N + 1
the OV pin
< V
> V
TIMER
OV(OFF)
UV(OFF)
N > 10
POR is generated
MOSFET → OFF
DISABLE = 0
Filter = 1.0 ms
DISABLE
PG = 0
N = 0
34652 STATE MACHINE DIAGRAM
different modes of operation.
N ≤ 10
Toggle DISABLE
or cycle Power Off
then On to clear fault
Retry Fault
Figure 13
STOP
Figure 14. Undervoltage Fault Followed by a
Charging Mode
Filter = 1.0 ms
DISABLE = 1
is a representation of the 34652 behavior in
New Start-Up Sequence
Normal Operation
Pass PG
Check
Fail PG
Check
V
PG = 1
N = 0
DS
< 500 mV
I
FUNCTIONAL DEVICE OPERATION
LOAD
and V
I
LOAD
Fast Gate Discharge
Good Check
If I
> I
I
for 20 ms
LOAD
LOAD
for 100 μs
Short Circuit
SHORT
DS
Power
< I
Detection
< 10 μs
PROTECTION FEATURES
< 500 mV
LIM
< I
> I
MOSFET → OFF
LIM
LIM
- I
LIMHY
Overcurrent Mode
Overcurrent
for > 3.0 ms
Turn Off
PG = 0
Filter = 3.0 ms
34652
15