PCA9952TW,118 NXP Semiconductors, PCA9952TW,118 Datasheet - Page 22

• Manufacturer Part Number: PCA9952TW,118
• Description: LED Lighting Drivers 16-ch Fm+ I2C-bus 57 mA LED driver
• Manufacturer: NXP Semiconductors

Specifications of PCA9952TW,118

• Rohs: yes
• Input Voltage: 3 V to 5.5 V
• Operating Frequency: 31.25 kHz
• Maximum Supply Current: 15 mA
• Output Current: 62 mA
• Mounting Style: SMD/SMT
• Package / Case: HTSSOP-28
• Factory Pack Quantity: 2500

NXP Semiconductors
PCA9952_PCA9955
Product data sheet
7.3.16.2 Short-circuit detection principle
7.3.17 Overtemperature protection
7.4 Active LOW output enable input
[1]
The LED short-circuit detection compares the effective voltage level (V
shorted-load detection threshold voltages V
PCA9952/55 detects a shorted-load condition. If V
is detected or error bit is reset. This error status can be read out as an error flag through
the registers EFLAG0 and EFLAG1. For short-circuit error detection, a channel must be
on.
Table 21.
[1]
Remark: The error status does not distinguish between an LED short condition and an
LED open condition. When an LED fault condition is noted, the LEDn outputs should be
turned off to prevent heat dissipation in the chip and the repair should be done.
If the PCA9952/55 chip temperature exceeds its limit (T
channels will be disabled until the temperature drops below its limit minus a small
hysteresis (T
OVERTEMP flag (bit 7) is set in the MODE2 register. Once the die temperature reduces
below the T
overtemperature event and the OVERTEMP flag will be cleared.
Remark: Only the PCA9952 has the OE pin.
The active LOW output enable (OE) pin on PCA9952 allows to enable or disable all the
LEDn outputs at the same time.
The OE pin can be used as a synchronization signal to switch on/off several PCA9952
devices at the same time. This requires an external clock reference that provides blinking
period and the duty cycle.
The OE pin can also be used as an external dimming control signal. The frequency of the
external clock must be high enough not to be seen by the human eye, and the duty cycle
value determines the brightness of the LEDs.
State of
output port
OFF
ON
•
•
I
R
V
When a LOW level is applied to OE pin, all the LEDn outputs are enabled.
When a HIGH level is applied to OE pin, all the LEDn outputs are high-impedance.
th(det)
th
ext
 2.5 V.
.
= 0.5  I
Shorted-load detection
th(otp)
hys
O(target)
, see
All information provided in this document is subject to legal disclaimers.
 T
Condition of
output voltage
-
V
V
O
O
hys
 V
< V
Table
(typical). This threshold may be different for each I/O and only depends on IREFx and
, the chip will return to the same condition it was prior to the
th(trig)
th(trig)
Rev. 6 — 22 April 2013
16-channel Fm+ I
24). When an overtemperature situation is encountered, the
[1]
[1]
Error status code
0
1
channel n error status bit 0
th(trig)
2
C-bus 57 mA constant current LED driver
PCA9952; PCA9955
. If V
O
is below the V
O
is above the V
th(otp)
, see
th(trig)
Table
Description
detection not possible
short-circuit
normal
th(trig)
O
threshold, no error
© NXP B.V. 2013. All rights reserved.
) with the
24), all output
threshold, the
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