34709 View Datasheet(PDF) - Freescale Semiconductor

Part Name

Description

Manufacturer

34709

Power Management Integrated Circuit (PMIC) for i.MX50/53 Families

Freescale Semiconductor 

General Product Characteristics

Table 5. Thermal Ratings (continued)

All voltages are with respect to ground, unless otherwise noted. Exceeding these ratings may cause a malfunction or permanent

damage to the device.

Symbol

Description (Rating)

Min.

Max.

Unit Notes

THERMAL RESISTANCE AND PACKAGE DISSIPATION RATINGS (CONTINUED)

Junction to Package Top

JT

• Natural Convection

(10)

-

6.0

°C/W

Notes

3. Pin soldering temperature limit is for 10 seconds maximum duration. Not designed for immersion soldering. Exceeding these limits may

cause a malfunction or permanent damage to the device.

4. Freescale's Package Reflow capability meets the Pb-free requirements for JEDEC standard J-STD-020C, for Peak Package Reflow

Temperature and Moisture Sensitivity Levels (MSL).

5. Junction temperature is a function of on-chip power dissipation, package thermal resistance, mounting site (board) temperature, ambient

temperature, air flow, power dissipation of other components on the board, and board thermal resistance.

6. Per JEDEC JESD51-2 with the single layer board horizontal. Board meets JESD51-9 specification.

7. Per JEDEC JESD51-6 with the board horizontal.

8. Thermal resistance between the die and the printed circuit board per JEDEC JESD51-8. Board temperature is measured on the top

surface of the board near the package.

9. Thermal resistance between the die and the case top surface as measured by the cold plate method (MIL SPEC-883 Method 1012.1).

10. Thermal characterization parameter indicating the temperature difference between package top and the junction temperature per

JEDEC JESD51-2. When Greek letters are not available, the thermal characterization parameter is written as Psi-JT.

5.2.1 Power Dissipation

During operation, the temperature of the die should not exceed the maximum junction temperature. To optimize the thermal

management scheme and avoid overheating, the 34709 PMIC provides a thermal management system. The thermal protection

is based on a circuit with a voltage output that is proportional to the absolute temperature. This voltage can be read out via the

ADC for specific temperature readouts, see Serial Interfaces.

This voltage is monitored by an integrated comparator. Interrupts THERM110, THERM120, THERM125, and THERM130 will be

generated when respectively crossing in either direction of the thresholds specified in Table 6. The temperature range can be

determined by reading the THERMxxxS bits.

Thermal protection is integrated to power off the 34709 PMIC, in case of over dissipation. This thermal protection will act above

the maximum junction temperature to avoid any unwanted power downs. The protection is debounced for 8.0 ms in order to

suppress any (thermal) noise. This protection should be considered as a fail-safe mechanism and therefore the application

design should be dimensioned such that this protection is not tripped under normal conditions. The temperature thresholds and

the sense bit assignment are listed in Table 6.

Table 6. Thermal Protection Thresholds

Parameter

Thermal 110 °C threshold (THERM110)

Thermal 120 °C threshold (THERM120)

Thermal 125 °C threshold (THERM125)

Thermal 130 °C threshold (THERM130)

Thermal warning hysteresis

Thermal protection threshold

Notes

11. Equivalent to approx. 30 mW min, 60 mW max

Min

Typ

Max

105

110

115

115

120

125

120

125

130

125

130

135

2.0

-

4.0

130

140

150

Units

°C

°C

°C

°C

°C

°C

Notes

(11)

34709

13

Analog Integrated Circuit Device Data

Freescale Semiconductor

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