MAX8555AEVKIT Maxim Integrated Products, MAX8555AEVKIT Datasheet - Page 4

• Manufacturer Part Number: MAX8555AEVKIT
• Description: EVAL KIT FOR MAX8555
• Manufacturer: Maxim Integrated Products

Specifications of MAX8555AEVKIT

• Main Purpose: Power Management, ORing Controller / Load Share
• Utilized Ic / Part: MAX8555A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Secondary Attributes: -
• Embedded: -
• Primary Attributes: -

MAX8555A Evaluation Kit
The GATE pin on the MAX8555A controller provides the
necessary gate drive for both MOSFETs in each circuit
on the EV kit. The GATE voltage can be monitored with
an oscilloscope (10MΩ impedance) connected to test
point TP1 or TP2 on the EV kit board, and should read
5V (typ) above the CS+ voltage. During startup, the
GATE voltage ramp-up time is determined by the
charge-pump frequency that is programmed by the
TIMER pin.
The MAX8555A controller features a dual-purpose
TIMER input that sets the charge-pump frequency or
functions as a logic enabler. The MAX8555A EV kit cir-
cuits provide two 2-pin jumpers, JU1 and JU2, to con-
figure the TIMER pin. Place a shunt across jumper JU1
or JU2 to connect the TIMER pin to ground through
resistor R7 or R15 to set the charge-pump frequency to
250kHz. Removing the shunts from jumper JU1 or JU2
leaves the TIMER pin floating on the associated circuits
Table 1. MAX8555A FAULT MODES
Table 2. Jumpers JU1 and JU2
*User may connect to the TIMER PC pad and supply a logic-high signal of 2.5V or 3.3V.
4
Reverse-Current Protection
_______________________________________________________________________________________
Undervoltage Protection
Overvoltage Protection
FAULT MODE
V
SHUNT LOCATION
DD
Not installed
OVP
Installed
(when shunts are connected across
V
MOSFETs are ON for t > 4.1ms
V
IN
OUT
1 or V
EV KIT CONDITIONS
JU1 or JU2 t > 8.2ms)
V
IN
> 2V and V
V
Connected to ground through resistor
R7/R15
Floating
(connected to the TIMER PC pad*)
DD
1 or V
IN
V
GATE Drive
OUT
2 < V
> 14.4V (typ)
IN
+ 0.01V
OUT
TIMER
2 < 0.75V
IN
1 or V
- 0.02V and
TIMER PIN
IN
2 >
and sets the charge-pump frequency to 500kHz. An
open-drain/open-collector transistor can also be con-
nected to the TIMER PC pad to control the MAX8555A
controller. Assert a logic-low signal (below 0.5V) to the
TIMER pad to shut down the controller. Verify that the
shunts are removed from jumpers JU1 and JU2 when
using an external device to control the MAX8555A. See
Table 2 for jumpers JU1 and JU2 configuration.
The charge-pump frequency can be adjusted between
100kHz and 500kHz by replacing resistor R7 or R15.
Use the following equation to select a new 1% toler-
ance resistor value for R7 or R15.
where f is the desired charge-pump frequency in kHz
and R
TIMER
MOSFETs
Off
Off
Off
Off
is the value of resistor R7 or R15.
R
TIMER
Normal operation, charge-pump
frequency programmed to 250kHz,
blank time = 8.2ms
Normal operation, charge-pump
frequency defaults to 500kHz,
blank time = 4.1ms
FAULT2 OUTPUT
=
FAULT1 AND
100µ
Low
Low
Low
Low
EV KIT FUNCTION
A
1 25
-
.
5kHz/
V
f
µ
A
LATCHING
Yes
Yes
No
No